Sagi's Tech

Enum.GetValues does not exist on Windows Phone

2012-03-11T04:48:00.005-07:00

Enum.GetValues does not exist on Windows Phone. The solutions here and here requires LINQ.

I've changed the solutions so they would fit Windows Phone without LINQ. I also reduced memory allocations (not using enumerators and generic collections):

public static T[] GetValues<T>()
{
   Type enumType = typeof(T);
   if (!enumType.IsEnum)
      throw new ArgumentException("Type '" + enumType.Name + "' is not an enum");

   FieldInfo[] fields = enumType.GetFields();
   int literalCount = 0;
   for (int i = 0; i < fields.Length; i++)
      if (fields[i].IsLiteral == true)
         literalCount++;

   T[] arr = new T[literalCount];
   int pos = 0;
   for (int i = 0; i < fields.Length; i++)
      if (fields[i].IsLiteral == true)
      {
         arr[pos] = (T)fields[i].GetValue(enumType);
         pos++;
      }

   return arr;
}

Android Market Optimization

2012-02-20T22:16:00.000-08:00

This subject also known as App Store Optimization (ASO). Few people started to write posts on this subject for Android, this post is an on-going work to collect links to those posts:

There's a series of posts on Droid-Blog blog: Keyworks & Description, Icons, Graphics & Videos
A post called Hacking the app stores

Android promotion: pay per install

2012-02-15T22:43:00.000-08:00

I tried looking for ways to promote Android apps. It was hard. Why companies aren't saying: we're doing Pay-Per-Install campaigns? (alternative names include: Cost-Per-Install, CPI, Cost-Per-Action, CPA)

Here's a list of pay-per-install for Android I've found so far (on going work, please correct me if there's something wrong here):

AppBrain - Free apps only, Minimum bid: 0.20$, minimal daily budget: 25$, minimal campaign budget: 100$. See more details here.
TapJoy - Pay-per-install plus optional pay-per-action (which probably cost much more). Couldn't find minimal prices for pay-per-install.
RadiumOne - ???
W3I - ???
Flurry AppCircle - Free & paid apps. Minimum bid: 0.75$
Everbadge - Free & paid apps. Minimum bid: 0.15$
AppRedeem - Free & paid apps. Minimum bid: 0.50$ (paid apps), 0.15$ (free apps)
HeyZap - ???

References:

https://groups.google.com/forum/#!msg/android-discuss/tlYilbiPhDc/nxKsnze59tEJ
User comment: updated Everbadge minimum bid.

Downloading Android source code on Windows

2012-01-30T02:17:00.001-08:00

Here's the short-short version:

Download and install command line Git client: msysgit.
Download the root Android project using Git.exe (located in /bin folder of msysgit)
git clone https://android.googlesource.com/platform/manifest
In the target folder you'll find few XML files. Open default.xml. You can see multiple tags . Choose the project you want to download. You need the name attribute of the project. Write the following line to download:
git clone https://android.googlesource.com/

Example:
To download the most interesting project (IMHO) frameworks/base, the GIT command is:
git clone https://android.googlesource.com/platform/frameworks/base

Projects of interest:

packages/apps/XXXX - The project names of the apps that comes bundled with Android (excluding proprietry Google apps such as the Android Market) such as the Gallery, Camera etc.
external/XXXX - 3rd party software (ping, bzip, etc).
frameworks/base - The sources of the Java system.

Android (Java) object pool

2012-01-21T22:42:00.000-08:00

There are many ways to implement an object pool. Here's the way it's implemented in some classes in Android (Message, MotionEvent, Parcel, VelocityTracker):


private MyObjectName next;
private static Object mPoolSync = new Object();
private static MyObjectName mPool;
private static int mPoolSize = 0;
private static final int MAX_POOL_SIZE = 10;

public static MyObjectName obtain() {
  synchronized (mPoolSync) {
    if (mPool != null) {
      MyObjectName m = mPool;
      mPool = m.next;
      m.next = null;
      return m;
    }
  }
  return new Message();
}

public void recycle() {
  synchronized (mPoolSync) {
    if (mPoolSize < MAX_POOL_SIZE) {
      clearForRecycle();
                
      next = mPool;
      mPool = this;
    }
  }
}

Reducing ArrayList add()/remove() memory re-allocation/shifts

2012-01-11T04:22:00.000-08:00

This post is Android related, but probably goes to all java systems.

Reason: ArrayList implementation is based on an array, with a pointers to the start and end of the array.
(1) When you remove the first or last items, the pointers are moved. If you remove and items from the middle all the items after the removed location are shifted.
(2) After many removes/adds the start pointer is set so high the ArrayList is forced to shift all the items.

Solution: when removing item - swap the item with the last item, and remove the last item. Drawback - you lose the order of the items in the ArrayList.

import java.util.ArrayList;
import java.util.ArrayList;
import java.util.Collection;

public class SwapArrayList extends ArrayList {
 private static final long serialVersionUID = 2995040970224168173L;

 public SwapArrayList() {
        this(0);
    }

    public SwapArrayList(int capacity) {
     super(capacity);
    }

    public SwapArrayList(Collection collection) {
     super(collection);
    }
    
    @Override
    public boolean remove(Object object) {
        int index = indexOf(object);
        if (index >= 0) {
         int size = this.size();
         if (index < size - 1) {
          // Swap the last item with the item to be removed
       E tmp = this.get(size - 1);
       this.set(size - 1, this.get(index));
       this.set(index, tmp);
       index = size - 1;
         }
         
            remove(index);
            return true;
        }
        return false;
    }
    
    @Override
    public E remove(int location) {
     int size = this.size();
     if (0 <= location && location < size) {
      if (location < size - 1) {
       // Swap the last item with the item to be removed
       E tmp = this.get(size - 1);
       this.set(size - 1, this.get(location));
       this.set(location, tmp);
       location = size - 1;
      }
     } else {
      throw new IndexOutOfBoundsException();
     }
     
     return super.remove(location);
    }
}

onKeyDown/onKeyUp/onTrackballEvent does not fire in a View

2012-01-08T04:56:00.000-08:00

When trying to get keypad events in a view, the view does not get those events unless explicitly sent by the Activity, so to fix this add the following code in the Activity:


@Override
public boolean onTrackballEvent(MotionEvent event) {
    if (mView.dispatchTrackballEvent(event) == true)
        return true;
       
    return super.onTrackballEvent(event);
}

Finding table by column name in a database

2011-12-15T01:35:00.000-08:00

From time to time I need to find a table in a database which I know the column name but I have to search for the table.

Here's how to do it in Oracle:
SELECT TABLE_NAME, COLUMN_NAME
FROM USER_TAB_COLUMNS -- COLS,
WHERE COLUMN_NAME = 'ColumnNameHere'
GROUP BY TABLE_NAME, COLUMN_NAME;

Here's how to do it in SQL Server:
SELECT obj.Name, col.Name
FROM sysobjects obj, syscolumns col
WHERE obj.id = col.id
AND col.Name = 'ColumnNameHere'

Protected free Android applications

2011-11-24T06:11:00.000-08:00

One issue I'm facing from time to time is people copying my apps & change the ad network code.

I found the following methods good fighting them:

Use ProGuard to obfuscate the code. If the code is obfuscated it's harder to remove other protective measures listed below. Some notes on ProGuard:
(a) Move important functionality from non-obfuscated functions (such as onCreate)
Check application signature, use: getPackageManager().getPackageInfo(getPackageName(), PackageManager.GET_SIGNATURES).signatures[0]
CRC/Checksum validation of resources
CRC/Checksum validation of the APK.
Check if the application is running in debugger.
Check installed package name.

When you discover an issue DO NOT stop the application. Start a sequence that will cause the application crash (for example, clear a list that should not be empty).

AndEngine BitmapTextureAtlas extension

2011-10-24T23:28:00.000-07:00

Last few days I played with AndEngine, an open source, free, games framework for Android. I'm not sure yet if AndEngine will save time building new games.

Anyhow, one weird part in AndEngine is the way you load all the resources into a single canvas. You have to define the location of each resource on the canvas, and if you change the resource size you have to recalculate everything.

Here is a simple extension to BitmapTextureAtlas that calculate everything automatically and saves you the trouble of positioning the resources on the canvas.

public class BitmapTextureAtlasEx extends BitmapTextureAtlas {
 int mUsedWidth;
 
 public BitmapTextureAtlasEx(int width, int height, TextureOptions options) {
  super(width, height, options);
  
  mUsedWidth = 0;
 }
 
 public TextureRegion appendTextureAsset(Context c, String assetPath) {
  TextureRegion region = BitmapTextureAtlasTextureRegionFactory.createFromAsset(
         this, c, assetPath, mUsedWidth, 0);
  mUsedWidth += region.getWidth();
  
  return region;
 }
 
 public TiledTextureRegion appendTiledAsset(Context c, String assetPath, int tiledColumns, int tiledRows) {
  TiledTextureRegion region = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(
         this, c, assetPath, mUsedWidth, 0, tiledColumns, tiledRows);
  mUsedWidth += region.getWidth();
  
  return region;
 } 
}

And this is how to use it (in the onLoadResources funcation):

mTexture = new BitmapTextureAtlasEx(1024, 128, TextureOptions.BILINEAR_PREMULTIPLYALPHA);
      
mTextureRegion = this.mTexture.appendTextureAsset(this, "texture.png");
mTiledRegion = this.mTexture.appendTiledAsset(this, "tile.png", 1, 1);

Free resources for applications

2011-10-18T05:55:00.000-07:00

This post is a work in progress.

Here are few places I've found for useful for free resources. You should verify if the specific resource license fit your needs.

Free fonts:
*. http://www.fontsquirrel.com/ (verify the copy rights per font, most are not really free)
*. http://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&id=OFL (read the OFL license first)

Free clip arts:
*. http://www.openclipart.org/.
*. Huge list of sites that contain free images.

Free music/sound affects:
*. http://www.freesound.org - Creative common license.
*. There are many sites that looks OK, just search for 'free sound effects'.

A bit off-topic - royalty free resources (not free):
*. Music loops

Monetizing Android applications

2011-10-11T02:57:00.000-07:00

In a recent talk I've heard by Itay Rokni of StartApp.com he listed the various monetizing options Android developer has (to date):

In app ads - Ads inside the application: banners, full page, leads generators etc. See for example AdMob.

Paid apps - The user pay to get the application. Not free options.

Freemium - Basic application is free, the user can buy the full application or in-app buy more features.

Notification bar ads - Ads that appear not inside the application, but in the notification bar. For example see airpush.com.

Search icon - Create a search icon after app installation. The provider pay per installation or revenue share. For example see StartApp.com

Few notes if you're using In app ads:

Trust no one - AdMob is the industry benchmark and every says 'we're better than AdMob'. I found this statement to be almost always wrong.

Use mediation layer - Use mediation layer such as AdWhirl to control which ad networks you're using. Ad networks go up and down, it's better to control the follow of ads dynamically and not depend on updating the APK in the market.

Bulk image resizing/changing format

2011-09-27T20:31:00.000-07:00

Sometimes there's a need to resize images or just changes their formats. Mostly if the original is on high resolution or improper format for mobile applications. While there are many tools to do this, the best I've found is a plug-in for Paint.NET called Paint.NET Bulk Image Processor. It's free, open source and super easy to use.

innerActive & AdWhirl, take 2

2011-08-10T05:30:00.000-07:00

Few days ago I've published a post how to make an AdWhirl adapter for innerActive. Just after publishing the post I've noticed innerActive released a major version for their Android SDK (3.0.3).

Here is the new adapter:

import android.app.Activity;

import android.util.Log;

import android.view.View;



import com.adwhirl.AdWhirlLayout;

import com.adwhirl.AdWhirlLayout.AdWhirlInterface;

import com.inneractive.api.ads.InneractiveAdEventsListener;

import com.inneractive.api.ads.InneractiveAdView;

import com.inneractive.api.ads.InneractiveAdComponent;



public class InnerActiveCustomEvents implements AdWhirlInterface {

	private static final String INNERACTIVE_PUBLISHER_ID = "TBD";

	

	private AdWhirlLayout mAdWhirlLayout;

	private Activity mActivity;



	public AdWhirlMultipleCustomEvents(AdWhirlLayout mAdWhirlLayout, Activity mActivity) {

		super();

		this.mAdWhirlLayout = mAdWhirlLayout;

		this.mActivity = mActivity;

	}



	public void adWhirlGeneric() {

	}

	

	public void inneractiveBanner() {

	    // BUGBUG - This fixes the Android OS bug with 'getCacheTotalSize' which causes

		// NullPointerException prior to Android 2.3, see also:

		// http://code.google.com/p/android/issues/detail?id=10789

		android.webkit.WebViewDatabase webViewDB = android.webkit.WebViewDatabase.getInstance(mActivity);

		if (webViewDB == null) {

			mAdWhirlLayout.rollover();

			return;

		}

		

		InneractiveAdView banner = InneractiveAdComponent.getAdView(mAdWhirlLayout.getContext(), INNERACTIVE_PUBLISHER_ID, InneractiveAdComponent.BANNER_AD_TYPE, 0);



		banner.setListener(new InneractiveAdEventsListener() {			

			@Override

			public void onReceiveAd(InneractiveAdView adView) {

				adView.setVisibility(View.VISIBLE);

				Log.v("InnerActive Banner Listener", "Received Ad.");



				mAdWhirlLayout.handler.post(new AdWhirlLayout.ViewAdRunnable(mAdWhirlLayout, adView));

				mAdWhirlLayout.adWhirlManager.resetRollover();

				mAdWhirlLayout.rotateThreadedDelayed();   				

			}

			

			@Override

			public void onFailedToReceiveAd(InneractiveAdView adView) {

				Log.v("InnerActive Banner Listener", "Failed To Receive Ad.");

				mAdWhirlLayout.rollover();

			}

			

			@Override

			public void onClickAd(InneractiveAdView adView) {

			}

		});

	}

}

Using innerActive ads on Android (with AdWhirl)

2011-08-04T05:04:00.000-07:00

UPDATE- This post is obsolete, please check this update post.

I've decided to try using multiple ad agencies, and one of them was innerActive. I had 2 problems with innerActive: (1) They don't supply an AdWhirl adapter, (2) There's seem to be a bug in their SDK as of version 2.0625

Problem A: The bug
The function onWindowFocusChanged which runs on the UI thread calls the function setRefreshInterval which has the keyword synchronized which means it waits for a lock. The lock is taken by the ad request thread. If the onWindowsFocusChanged will be called during an ad request there will be an ANR exception due to a delay on the UI thread.

Solution:
I wrote a wrapper that seems to fix this issue.

import java.util.concurrent.locks.ReentrantLock;



import android.content.Context;

import android.util.AttributeSet;



import com.innerActive.ads.InnerActiveAdView;



public class InnerActiveAdViewFixed extends InnerActiveAdView {

private ReentrantLock mLock = new ReentrantLock();



public InnerActiveAdViewFixed(Context context) {

 super(context);

}



public InnerActiveAdViewFixed(Context context, AttributeSet attrs) {

 super(context, attrs);

}



public InnerActiveAdViewFixed(Context context, AttributeSet attrs, int defStyle) {

 super(context, attrs, defStyle);

}



// Patch

@Override

public void onWindowFocusChanged(boolean hasWindowFocus) {

 if (mLock.tryLock() == true) {

  try {

   super.onWindowFocusChanged(hasWindowFocus);

  } finally {

   mLock.unlock();

  }

 }

}



@Override

public byte start() {

 mLock.lock();

 try {

  return super.start();

 } finally {

  mLock.unlock();

 }

}

}

Problem B: No AdWhirl adapter
Solution:
I wrote a custom AdWhirl adapter for innerActive.

import android.util.Log;

import android.view.View;



import com.adwhirl.AdWhirlLayout;

import com.adwhirl.AdWhirlLayout.AdWhirlInterface;

import com.innerActive.ads.InnerActiveAdView;



public class InnerActiveCustomEvents implements AdWhirlInterface{

private AdWhirlLayout mAdWhirlLayout;



public InnerActiveCustomEvents(AdWhirlLayout adWhirlLayout) {

 super();

 this.mAdWhirlLayout = adWhirlLayout;

}



@Override

public void adWhirlGeneric() {

}



public void inneractiveBanner() {

 final InnerActiveAdViewFixed banner = new InnerActiveAdViewFixed(mAdWhirlLayout.getContext());

 banner.setVisibility(View.VISIBLE);

 banner.setRefreshInterval(0);

 banner.setScrollContainer(true);

 banner.setBgColor(0xFF000000);

 banner.setTxtColor(0xFFFFFFFF);



 banner.setListener(new InnerActiveAdView.AdEventsListener() {

 

  @Override

  public void onReceiveAd(InnerActiveAdView arg0) {

   banner.setVisibility(View.VISIBLE);

   Log.v("InnerActive Banner Listener", "Received Ad.");



   mAdWhirlLayout.handler.post(new AdWhirlLayout.ViewAdRunnable(mAdWhirlLayout, banner)); 



   mAdWhirlLayout.adWhirlManager.resetRollover();

   mAdWhirlLayout.rotateThreadedDelayed();   

  }

 

  @Override

  public void onFailedToReceiveAd(InnerActiveAdView arg0) {

   Log.v("InnerActive Banner Listener", "Failed To Receive Ad.");   

   mAdWhirlLayout.rollover();   

  }

 });   

}

}

I'm not going to write a step-by-step guide, but here is the key notes:

Integrate innerActive ads & make sure everything works.
Remove the ad view from the layout & the appropriate code the the ad view.
Integrate AdWhirl:
3.1. Create an application in AdWhirl web site & get SDK Key
3.2. Add AdWhirl JAR
3.3. Add the AdWhirl SDK Key to the AndroidManifest.xml
3.4. Add the com.adwhirl.AdWhirlLayout to the application layout
Add the following code (in the onCreate functions)
AdWhirlLayout adWhirlLayout = (AdWhirlLayout)findViewById(R.id.adwhirl_layout);
adWhirlLayout.setAdWhirlInterface(new InnerActiveCustomEvents(adWhirlLayout));
Add innerActive to AdWhirl as custom event - name: innerActive, function name: inneractiveBanner

Notes -

If you're using multiple custom events, they should all be in the same function, so copy only the inneractiveBanner function.

If you're using ProGaurd make sure you read my previous post & also add the custom events adapter & innerActive ad views to the ProGuard exceptions list.

ProGuard & AdWhirl

2011-07-15T23:56:00.000-07:00

Compilation of an application with AdWhirl & ProGuard throws many warning, for all those AdWhirl adapter libraries not compiled with the application. I found multiple solutions online, some saying just ignore all the warning ProGuard throws:
-ignorewarnings

Don't use it - there's a better solution, ignoring only the problematic parts:
-dontwarn com.adwhirl.adapters.*

Here's the best solution for Proguard & AdWhirl as far as I know:

-dontwarn com.adwhirl.adapters.*

-keep class com.adwhirl.** { *;}
-keep public class com.adwhirl.adapters.AdMobAdapter {*;}
-keep public class com.adwhirl.adapters.ZestAdzAdapter {*;}
-keep public class com.adwhirl.adapters.MillennialAdapter {*;}
-keep public class com.admob.android.ads.** {*;}
-keep public class com.millennialmedia.android.** {*;}
-keep public class com.zestadz.android.** {*;}

-keep public class * extends Android.view.View {
public (android.content.Context);
public (android.content.Context, android.util.AttributeSet);
public (android.content.Context, android.util.AttributeSet, int);
public void set*(...);
}

-keepclassmembers class *{
public void *(android.view.View);
}

Error conversion to Dalvik format failed with error 1

2011-07-10T04:13:00.000-07:00

UPDATE: This issue still exists as of SDK Tools 15. You should use Solution 2.

There is a bug in the latest Android SDK Tools (revisions 12, 13, 14 & 15) which cause the following error:
Error conversion to Dalvik format failed with error 1
when you try to export your Android application & got Proguard enabled.

Google will probably fix it within few days, until then DO NOT UPDATE to Android SDK Tools revision 12. Someone already opened a bug on this issue.

Solution 1 - Restore SDK Tools v11 (ugly but it works):
If you did upgrade, the instructions how to install Android SDK Tools v11 on top can be found here. I did something similar which I think is safer & easy to undo:
1. Download Android SDK Tools v11 installer from here: http://dl.google.com/android/installer_r11-windows.exe
2. Rename the existing Android SDK\Tools folder to Tools-v12
3. Open the installer using 7zip, go to folder $_OUTDIR, and copy the folder 'Tools' the the position under Android SDK folder.

Solution 2 - Upgrade to Proguard 4.7 (needs to be reapplied after every SDK Tools upgrade):
Manually update Proguard to version 4.7. You'll have to do it again after each update of the SDK Tools.
1. Download Proguard 4.7 (zip): http://sourceforge.net/projects/proguard/files/proguard/4.7/
2. Extract the folders "bin" & "lib" from the zip on top the existing Proguard installation in the SDK Tools Proguard folders "bin" & "lib", should be around here (Win x64):
C:\Program Files (x86)\Google\Android SDK\tools\proguard

Android SDK Error: Unable to resolve target 'Google Inc.:Google APIs:X'

2011-06-20T07:59:00.000-07:00

I the past I wrote a post on a similar issue, but here goes -
There are few variants of this error message:
Unable to resolve target 'Google Inc.:Google APIs:1'
Unable to resolve target 'Google Inc.:Google APIs:2'
Unable to resolve target 'Google Inc.:Google APIs:3'
Unable to resolve target 'Google Inc.:Google APIs:4'
Unable to resolve target 'Google Inc.:Google APIs:5'
Unable to resolve target 'Google Inc.:Google APIs:6'
Unable to resolve target 'Google Inc.:Google APIs:7'
Unable to resolve target 'Google Inc.:Google APIs:8'
Unable to resolve target 'Google Inc.:Google APIs:9'
Unable to resolve target 'Google Inc.:Google APIs:10'
Unable to resolve target 'Google Inc.:Google APIs:11'
Unable to resolve target 'Google Inc.:Google APIs:12'
Unable to resolve target 'Google Inc.:Google APIs:13'
Unable to resolve target 'Google Inc.:Google APIs:14'
Unable to resolve target 'Google Inc.:Google APIs:15'

Reason: Could not find the proper Google APIs Android SDK version. If the android SDK is installed correctly the problem is that the platform SDK requested by the "AndroidManifest.xml" android:minSdkVersion is not installed. For example:
'Google Inc.:Google APIs:1' - Upgrade the requested SDK
'Google Inc.:Google APIs:2' - Upgrade the requested SDK
'Google Inc.:Google APIs:3' - install Google APIs SDK Android 1.5
'Google Inc.:Google APIs:4' - install Google APIs SDK Android 1.6
'Google Inc.:Google APIs:5' - install Google APIs SDK Android 2.0
'Google Inc.:Google APIs:6' - install Google APIs SDK Android 2.0.1
'Google Inc.:Google APIs:7' - install Google APIs SDK Android 2.1
'Google Inc.:Google APIs:8' - install Google APIs SDK Android 2.2
'Google Inc.:Google APIs:9' - install Google APIs SDK Android 2.3
'Google Inc.:Google APIs:10' - install Google APIs SDK Android 2.3.3
'Google Inc.:Google APIs:11' - install Google APIs SDK Android 3.0
'Google Inc.:Google APIs:12' - install Google APIs SDK Android 3.1
'Google Inc.:Google APIs:13' - install Google APIs SDK Android 3.2
'Google Inc.:Google APIs:14' - install Google APIs SDK Android 4.0
'Google Inc.:Google APIs:14' - install Google APIs SDK Android 4.0.3

You can do this using the Android SDK Setup utility:
Option 1: Eclipse -
"Windows" -> "Android SDK and AVD Manager" -> "Available packages" -> "Third Party" -> "Google"

Option 2: Command line - start the "SDK Setup" here (x86):
C:\Program Files\Google\Android SDK\SDK Setup.exe
or here (x64)
C:\Program Files (x86)\Google\Android SDK\SDK Setup.exe

getCacheTotalSize causes NullPointerException

2011-06-01T00:10:00.000-07:00

After starting to use a new AdMob SDK I noticed the following exception in the Android Market Developer Console:http://www.blogger.com/img/blank.gif
java.lang.NullPointerException
at android.webkit.WebViewDatabase.getCacheTotalSize(WebViewDatabase.java:735)
at android.webkit.CacheManager.trimCacheIfNeeded(CacheManager.java:557)
at android.webkit.WebViewWorker.handleMessage(WebViewWorker.java:195)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:123)
at android.os.HandlerThread.run(HandlerThread.java:60)

I solved it using a suggestion I found online. You can use other ways to disable the ads, depending which SDK you use:


WebViewDatabase webViewDB = WebViewDatabase.getInstance(this);
if (webViewDB == null) {
  View adView = findViewById(R.id.adView);
  if (adView != null)
    adView.setVisibility(View.GONE);
}

Anyhow, as far as I remember this issue was fixed in the Android OS 2.3+, so until this OS version will catch you have to disable the ads to people with this problem.

Improving Remote Desktop speed on Vista/Win7

2011-05-24T17:54:00.000-07:00

A fellow kept complaining that his Remote Desktop (mstsc) connection to the office is super slow. I told him that I had the same problem since I moved from Windows XP to Windows 7 & he found the following solution:

Run the following command line:
netsh interface tcp set global autotuninglevel=disabled
to undo it:
netsh interface tcp set global autotuninglevel=normal

For full details check this post. It's not optimal, but it works & I didn't notice any problem since.

Memory debugging and Android application

2011-05-13T21:21:00.000-07:00

Using DDMS

*. Compile & run the application on an enumlator in debug (e.g. Manifest.xml, android:debuggable="true").
*. open DDMS

Checking the heap status:
*. Select your application, click on 'Show heap updates' on the toolbar.
*. Play around with your application and check the results.

Checking the allocations:
*. Select the allocation tracker tab, click on 'Start Tracking'
*. Press 'Get Allocations' when you want to check the allocations.

Note: do not use both heap status & allocations - the heap monitoring will cause a lot of allocations.

Display ListPreference value in the preferences screen

2011-05-03T04:22:00.000-07:00

One missing feature in the preferences activity in Android applications is to display the selected value of a ListPreference. By default, to view the selected value of a ListPreference you must click the preference and see what's selected in the combo box.

Here's an example how to create a preferences activity which displays the selected value of any number of ListPreferences in the activity.


public class MyPreferenceActivity extends PreferenceActivity 
  implements SharedPreferences.OnSharedPreferenceChangeListener {
    
    private ArrayList<ListPreference> mListPreferences;
    private String[] mListPreferencesKeys = new String[] {
     "prefKey1", // The 'android:key' value of the ListPreference
     "prefKey2"  // The 'android:key' value of the ListPreference
     ....
     ....
     ....
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        addPreferencesFromResource(R.xml.preferences);
        
        mListPreferences = new ArrayList<ListPreference>();
        SharedPreferences sharedPrefs = getPreferenceManager().getSharedPreferences();
        sharedPrefs.registerOnSharedPreferenceChangeListener(this);
        for (String prefKey : mListPreferencesKeys) {
         ListPreference pref = (ListPreference)getPreferenceManager().findPreference(prefKey);
         mListPreferences.add(pref);
         onSharedPreferenceChanged(sharedPrefs, prefKey);
        }
    }

    @Override
 public void onSharedPreferenceChanged(SharedPreferences pref, String prefKey) {
     for (ListPreference listPref : mListPreferences) {
      if (listPref.getKey().equals(prefKey))
       listPref.setSummary(listPref.getEntry());
     }
 }
}

Notes:

This code will update the values if the user selects a new value

If you're defining preferences keys in the strings.xml file, make the mListPreferencesKeys list an integer list, and get the string at run time using 'getString'

Problem uninstalling android application

2011-04-20T23:07:00.000-07:00

From time to time I'm facing an application that refuses to uninstall using the market. Here is the procedure I'm using (if any step works - there's no need to continue):

Uninstall using the Android Market application
Uninstall using the settings menu from the home screen: 'Menu' -> 'Settings' -> 'Applications' -> 'Manage Applications' -> select the application & uninstall.
Uninstall using a 3rd party tool, for example: ASTRO file manager (in the application click 'Menu' -> 'Tools' -> 'Application Manager/Backup' -> long click the application -> 'Uninstall')
Reboot the phone and try steps 2 & 3 again.

Performing research on the Android Market

2011-04-06T23:16:00.000-07:00

There are various out there that can help perform a research on Android applications.

Android Market application
Android Market web site - Has difference number of downloads scale. While the highest value in the Market application is >250K, in the web site there are different values: 50K-100K, 100K-500K, 500K-1M, 1M-5M, 5M-10M, 10M-50M
AndroLib - Has application rating (stars) history
AndroidZoom - Has application history: release dates & events (when the application passed a download group (e.g. 10K-50K, 50K-250K).
Android App Tracker - Has application market ranking history.

If you have more interesting sites, please share.

onActivityResult not called in time

2011-04-02T00:04:00.000-07:00

I wrote a small program that needed to use a preference screen. After the preferences were updated the application needs to update. To do that I used startActivityForResult to start the preferences screen, and onActivityResult to update the application.

Problem: onActivityResult wasn't called in time. Using Toast I've noticed it was called BEFORE the preferences screen opens.

Solution: In my case - the application was defined as launchMode=singleInstance, removing this put things back to place.

Note: This is true for Android 2.3.3. I didn't check the documentation to see if it's a normal behavior or an issue.

Problem uninstalling Android SDK samples

2011-02-13T05:35:00.000-08:00

This is the second time it happens to me so I've decided to write a post about it.

Problem: in the "Android SDK and AVD Manager"/"SDK Setup" selecting "Samples for SDK ..." package and clicking 'delete' deletes the content of the samples folder, but does not remove the entry from the "Android SDK and AVD Manager".

Solution:
1. Close the "Android SDK and AVD Manager"/"SDK Setup" (close the eclipse if it's running).
2. Delete the SDK specific samples folder. If the folder is locked kill any 'java.exe' process running (or reboot).
3. Restart the "Android SDK and AVD Manager"/"SDK Setup"

Distance on earth calculation in SQL

2011-02-13T04:18:00.000-08:00

Here's how to create an SQL function to calculate the distance (in KM) between to points on earth. This is an estimation since the distance is calculated as if the earth was round, but it's close enough for most purposes:


CREATE FUNCTION dist (@latFrom float, @longFrom float,@latTo float, @longTo float)
        RETURNS float
AS
BEGIN
        DECLARE @Distance float
        SET @Distance =
                (SIN(RADIANS(@latFrom)) *
                SIN(RADIANS(@latTo)) +
                COS(RADIANS(@latFrom)) *
                COS(RADIANS(@latTo)) *
               
                COS(RADIANS(@longFrom - @longTo)))
 
        SET @Distance = (DEGREES(ACOS(@Distance))) * 69.09 * 1.609344
       
        RETURN(@Distance)
END

TimePicker & DatePicker with keyboard edit problem

2011-01-21T08:53:00.000-08:00

Problem: When using the TimePicker & DatePicker objects in an AlertDialog (and probably anywhere else), the time & date seem to not to update when the user is editing the value using a keyboard (or soft keyboard).

Solution: Before calling the functions to get the date & time from the objects call TimePicker or DatePicker clearFocus() method.

I found few threads talking about this problem without a solution. I found the solution when I looked at the TimePickerDialog source code which did not suffer from this problem.

Android SQLite Alter Table

2011-01-21T03:14:00.001-08:00

When upgrading SQLite database sometimes you need to change the tables scheme. The problem is that SQLite Alter Table SQL format does not support all the options you might need (specifically - dropping columns, changing column types, renaming columns).

One way around this issue is to create a new table & copy the data to the new table. There are few options here, but the best way (I think) is as follows:
1. Create new table in the new format.
2. Copy the data.
3. Drop the original table
4. Rename the new table

For example:

BEGIN TRANSACTION;
CREATE TABLE t_new(a,b);
INSERT INTO t_new SELECT a,b FROM t;
DROP TABLE t;
ALTER TABLE t_new RENAME TO t;
COMMIT;

IMPORTANT: As far as I know 'execSQL' of 'SQLiteDatabase' will NOT run multiple commands. You should run each SQL command in a separate 'execSQL' call (the transaction can be handled from the SQLiteDatabase, not need for explicit SQL commands).

Build.VERSION.SDK_INT on Android 1.5

2011-01-20T04:12:00.000-08:00

It won't be long before all Android 1.5 devices will disappear, until then it's a good idea to support them. The problem is the 'Build.VERSION.SDK_INT' was introduced only on Android 1.6, and before that there were only string values.

Here's a work-around this issue - it will return the correct value for Android 1.5+:

public static int getSdkInt() {
   if (Build.VERSION.RELEASE.startsWith("1.5"))
       return 3;
 
   try {
       return HelperInternal.getSdkIntInternal();
   } catch (VerifyError e) {
       return 3;
   }
}

private static class HelperInternal {
   private static int getSdkIntInternal() {
       return Build.VERSION.SDK_INT;              
   }
}

Note: the internal class is required since the Java virtual machine checks if a class is valid before loading it. In our case, a java VM running Android 1.5 will not be able to load Build.VERSION.SDK_INT and will crash.

UPDATE: Added VerifyError catch to prevent exceptions on some weird Android 1.5 devices.

Finding Android screen orientation

2010-12-24T00:28:00.000-08:00

There are multiple way to get Android screen orientation (landscape/portrait), however some of them are problematic:
this.getWindowManager().getDefaultDisplay().getOrientation()
Is depricated

this.getWindowManager().getDefaultDisplay().getRotation()
Works only from Android 2.2

I Found this to be the best resource until now, since it's exists since API 1 & it's not deprecated, yet:
this.getResources().getConfiguration().orientation

Compare it with:
Configuration.ORIENTATION_LANDSCAPE
Configuration.ORIENTATION_PORTRAIT
Configuration.ORIENTATION_SQUARE

Spinner.setSelection doesn't work correctly

2010-12-14T10:48:00.000-08:00

Problem:
There are a lot of posts around regarding a problem with Spinner.setSelection(i) function. I encountered this issue when I've tried to replace the adapter in the Spinner and select a new item. The setSelection function seems like it's not working, but when I click the spinner the selected item was the correct one.

Solution:
Use Spinner.setSelection(i, true) instead

Multiple substitutions specified in non-positional format

2010-12-08T00:07:00.000-08:00

Since Android SDK 2.3 there's a new error:
error: Multiple substitutions specified in non-positional format; did you mean to add the formatted="false" attribute?

Description:
This error indicates you're using a string resource with %s in it. See how to use it here under 'Formatting strings'. In general, instead of:

Hello, %s! You have %d new messages.

Should be:

Hello, %1$s! You have %2$d new messages.

Can not find adb.exe after Android SDK update

2010-12-07T23:01:00.000-08:00

After updating the Android SDK I got the following message when I opened Eclipse:
Can not find C:\Program Files\Google\Android SDK\tools\adb.exe
Please check the Android plugin's preferences

And when I checked the adb.exe was really missing!

Solution:
Update the Android add-ins for Eclipse, in Eclipse: "Help" -> "Check for Updates".

The reason for this error (in my case) was that since SDK 2.3 the 'adb.exe' was moved to:
C:\Program Files\Google\Android SDK\platform-tools\adb.exe

UPDATE: ddms.bat does not work as well (can not find adb.exe). The work-around I'm using until I'll find a better solution is adding the platform-tools folder to the environment PATH variable.

AdMob as shows in Landscape but not in Portrait

2010-11-26T06:10:00.000-08:00

This was really weird. I added AdMob Ad to an Android application, and it didn't show. I tried rotating to landscape & the ad appeared.

Solution: I found the solution here - the AdMob ad must not be padded, or be in a padded container.

Android application installation stuck on "Downloading"/"Installation"

2010-11-08T22:14:00.000-08:00

Problem: Application installation hangs/stuck on "downloading" or "installing" from the Market. Reboot does not help.

Solution: Clearing the Android Market application cache -
* Menu => Settings => Applications => Manage Applications => "All" tab => Market
* Click on "Clear cache" (you might get 'Force Close' on the Market application after that).
* Reopen the market & download

Note: This is an issue with the Android Market application not the application you're downloading.

Attachment disappears after e-mail sent programatically

2010-10-14T02:48:00.000-07:00

I banged my head in the wall for about an hour to fix this issue.

I wrote a small function in Android that let the user send an e-mail from my application. Everything worked just fine, but when the e-mail was sent the attachment disappeared (the attachment appeared within the GMail client on the android device before sending).

Solution: use the external storage (SD Card) instead of the application cache. The GMail client probably can't access the application cache folder, buf for some reason it shows as if the attachment is OK in the client).

Android's ListView performance for large list

2010-10-12T01:03:00.000-07:00

I needed to use a large ListView however the performance of the ListView loading time was very poor. Since I've used SimpleAdapter to map the data to the layout I was forced to populate all the data when creating the SimpleAdapter.

The solution I've decided to take is creating an adapter specific for the task, which populate the data from the objects only during creation of the item's view.

This is the pseudo code (note that the object data retrieval should by lazy too):


public class MyObjectAdapter extends BaseAdapter {
 private ArrayList mData;
 private int mResource;
 private LayoutInflater mInflater;

 public TimeZoneDisplayAdapter(Context context, ArrayList data,
   int resource) {
  mData = data;
  mResource = resource;
  mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
 }

 @Override
 public int getCount() {
  return mData.size();
 }

 @Override
 public Object getItem(int position) {
  return mData.get(position);
 }

 @Override
 public long getItemId(int position) {
  return position;
 }

 @Override
 public View getView(int position, View convertView, ViewGroup parent) {
  View v;
  if (convertView == null) 
   v = mInflater.inflate(mResource, parent, false);
  else
   v = convertView;
   
  bindView(position, v);
  return v;
 }

 private void bindView(int position, View view) {
  MyObject o = mData.get(position);
  
  ((TextView)view.findViewById(R.id.list_item_resource_id)).setText(o.getData1());
  ......
  ......
  ......
 }
}

Note: there are few examples online how to load data to ListView using threads. This wasn't my problem, and it's like killing a fly with a sledge-hammer. The loading time of a specific item was very short, the problem was that there were simply too many items to load at construction time.

Making TextView clickable (http)

2010-10-08T09:26:00.000-07:00

The problem: I had a TextView which I wanted to make clickable, and open a web browser.

1. Brute force solution: change the TextView style to blue & underline. Set the onClick event to open web browser.

2. The following code:


SpannableString s = SpannableString.valueOf(entryText);
URLSpan span = new URLSpan(urlText);
s.setSpan(span, 0, entryText.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
mTextView.setText(s);
mTextView.setMovementMethod(LinkMovementMethod.getInstance());

AlertDialog with single selection & no radio button

2010-08-23T04:59:00.000-07:00

Current Android version AlertDialog.Builder default behavior of "setSingleChoiceItems" creates a list with radio buttons from which you can select.

I wanted to get this list without the radio button. After digging a bit in AlertDialog.Builder & AlertController.AlertParams I found the solution: instead of using setSingleChoiceItems use setAdapter.


     ArrayAdapter adapter = new ArrayAdapter(this, android.R.layout.select_dialog_item, itemActionsList);
     dialog.setAdapter(adapter,
       new OnClickListener() {
     @Override
     public void onClick(DialogInterface arg0, int arg1) {
      // Do something
      arg0.dismiss();
     }        
       });

Android hangs: "Waiting For Debugger"

2010-08-23T04:03:00.000-07:00

I developed an application that worked just fine, and then it started to hang with the message: "Waiting For Debugger". Even when I disconnected the device from the computer the application insisted that it's waiting for the debugger...

Solution:
1. Restart Eclipse [it's probably not needed].
2. Restart the Android device.

Android requires .class compatibility set to 5.0. Please fix project properties.

2010-08-20T21:34:00.000-07:00

I've created a new workspace in Eclipse & imported an Android project.

* Issue #1:
Android requires .class compatibility set to 5.0. Please fix project properties.

* Solution:
1. Fix project:
Package Explorer ->
Right click the project ->
"Android Tools" -> "Fix Project Properties"
2. Restart Eclipse:
"File" -> "Restart"

* Issue #2: The following error appears many times
The method xyz() of type ABC must override a superclass method

* Solution:
1. Fix the project again:
Package Explorer ->
Right click the project ->
"Properties" -> "Java Compiler" -> "Compiler Compliance Level" = 1.6

DataView RowFilter performance

2010-08-16T12:24:00.000-07:00

I needed to use DataView but the performance I got was very poor. Searching the web I found this resource which explains the root cause for this issue: after each RowFilter the DataView is re-indexed.

Searching a bit more yield the answer from Microsoft: don't use RowFilter if you don't have to. Use FindRows.

For my scenario, using FindRows instead of Row filter resulted in at least factor of 6 improvement (i.e. 1 second instead of 6).

Eclipse hangs during building Android projects workspace

2010-08-12T10:10:00.000-07:00

Problem: Eclipse kept on hanging during auto-building Android projects.
I found a resource which said (escalating solutions):
1. Clean the projects.
2. Create a new workspace & import all projects.
3. Reinstall Eclipse

After trying 1 & 2, I found the following weird solution:
- Remove the auto-build (Project => Build Automatically). Kill the Eclipse (since it hangs...)
- Restart Eclipse.
- Delete the 'gen' folder of all the projects (using the Package Explorer)
- Project => Clean (clean all projects)
- Build the projects

Don't know why it worked (at least until now).

Android/Eclipse: Project 'MyProject' is missing required source folder: 'gen'

2010-08-12T09:54:00.000-07:00

I'm having lots of problems with my Eclipse (when I'll solve them I'll write about it).

Anyhow, after creating a new project in a new workspace I get the following error:
Project 'MyProject' is missing required source folder: 'gen'
After building the project there's a second error:
The project cannot be built until build path errors are resolved

A temporary solution: in the Package Explorer delete gen folder. Rebuilding the project again will fix the problem. Why it's temporary? you'll have to do it with every new project.

Starting android calculator programmatically

2010-08-05T02:40:00.000-07:00

Here goes:


public static final String CALCULATOR_PACKAGE = 
 "com.android.calculator2";
public static final String CALCULATOR_CLASS = 
 "com.android.calculator2.Calculator";

public static void OpenCalculator(Context context) { 
 Intent i = new Intent();
 i.setAction(Intent.ACTION_MAIN);
 i.addCategory(Intent.CATEGORY_LAUNCHER);

 i.setFlags(
  Intent.FLAG_ACTIVITY_NEW_TASK | 
  Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED);
 i.setComponent(new ComponentName(
  CALCULATOR_PACKAGE, 
  CALCULATOR_CLASS));
 context.startActivity(i);
}

Colors in AlertDialog

2010-07-31T01:38:00.000-07:00

I wanted to use colors in AlertDialog and I found this post. It work great although the solution there is not full (there are features of AlertDialog that will not work). One issue with that post - the code & XML there can not be easily copied.

Here's that code again, with some changes/improvements:
* Renamed the class name to ColorAlertDialog
* ColorAlertDialog.Builder does not inherits AlertDialog.Builder. This caused some confusion (you could call function but they didn't do anything).
* Added functionality to ColorAlertDialog.Builder
* Fixed force-close on Android 1.5

Class (I've renamed the class):


import java.util.ArrayList;
import java.util.Iterator;

import android.app.AlertDialog;
import android.content.Context;
import android.content.res.TypedArray;
import android.content.res.Resources.Theme;
import android.graphics.PorterDuff.Mode;
import android.graphics.drawable.Drawable;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ImageView;

public class ColorAlertDialog extends AlertDialog {
 private static int NONE = -1;
 private int tint = NONE;

 /**
 * @param context
 * @param theme
 */
 protected ColorAlertDialog(Context context) {
  super(context);
  init();
 }

 /**
 * @param context
 * @param theme
 */
 protected ColorAlertDialog(Context context, int theme) {
  super(context, theme);
  init();
 }

 /**
 * 
 */
 private void init() {      
  final Theme theme = getContext().getTheme();
  final TypedArray attrs = theme.obtainStyledAttributes(new int[] { android.R.attr.tint });
  tint = attrs.getColor(0, NONE);
 }

 /* (non-Javadoc)
 * @see android.app.Dialog#show()
 */
 @Override
 public void show() {
  super.show();
  setTint(tint);
 }

 /**
 * @param tint
 */
 public void setTint(int tint) {
  this.tint = tint;

  if ( tint != NONE ) {
   Iterator vi = iterator(android.R.id.content);
   while ( vi.hasNext() ) {
    tintView(vi.next(), tint);
   }
  }
 }

 /**
 * Set the {@link tint} color for the {@link View}
 * 
 * @param v the {@link View} to change the tint
 * @param tint color tint
 */
 private static void tintView(final View v, final int tint) {
  if ( v != null ) {
   final Mode mode = Mode.SRC_ATOP;
   if ( v instanceof ImageView ) {
    final Drawable d = ((ImageView)v).getDrawable();
    if ( d != null ) {
     try {
     d.mutate().setColorFilter(tint, mode);
     } catch (Exception ex) {
      // Patch for Android 1.5
     }
    }
   }
   else {
    final Drawable d = v.getBackground();
    if ( d != null ) {
     d.setColorFilter(tint, mode);
    }
   }
  }
 }

 /**
 * @param button
 */
 public void setCancelButton(Button button) {
  button.setOnClickListener(new View.OnClickListener() {
   @Override
   public void onClick(View v) {
    cancel();
   }
  });
 }

 /**
 * @param button
 */
 public void setPositiveButton(Button button) { 
  button.setOnClickListener(new View.OnClickListener() {
   @Override
   public void onClick(View v) {
    dismiss();  
   }
  });
 }
 
 /**
 * Return a {@link ChildrenIterator} starting at the {@link ViewGroup}
 * identified by the specified resource id.
 *  
 * @param res resource id of the {@link ViewGroup} to start the iteration
 * @return iterator
 */
 public Iterator iterator(int res) {
  final ViewGroup vg = (ViewGroup)findViewById(res);
  return new ChildrenIterator(vg);
 }

 public static class Builder {
  private ColorAlertDialog dialog;

  public Builder(Context context) {
   dialog = new ColorAlertDialog(context);
  }

  public Builder(Context context, int theme) {
   dialog = new ColorAlertDialog(context, theme);
  }

  public ColorAlertDialog create() {
   return dialog;
  }

  public Builder setMessage(CharSequence message) {
   dialog.setMessage(message);
   return this;
  }

  public Builder setTitle(CharSequence title) {
   dialog.setTitle(title);
   return this;
  }

  public Builder setPositiveButton(int resId, OnClickListener listener) {
   return setPositiveButton(dialog.getContext().getString(resId), listener);
  }
  
  public Builder setPositiveButton(CharSequence text, OnClickListener listener) {
   dialog.setButton(BUTTON_POSITIVE, text, listener);
   return this;
  }

  public Builder setNegativeButton(int resId, OnClickListener listener) {
   return setNegativeButton(dialog.getContext().getString(resId), listener);
  }

  public Builder setNegativeButton(CharSequence text, OnClickListener listener) {
   dialog.setButton(BUTTON_NEGATIVE, text, listener);
   return this;
  }
    
  public Builder setIcon(int iconId) {
   dialog.setIcon(iconId);
   return this;
  }
  
  public Builder setCancelable(boolean flag) {
   dialog.setCancelable(flag);
   return this;   
  }
  
  public ColorAlertDialog show() {
   dialog.show();
   return dialog;
  }
 }
 
 public class ChildrenIterator implements Iterator {
  ArrayList list;
  private int i;
  
  public ChildrenIterator(ViewGroup vg) {
   super();
        
   if ( vg == null ) 
    throw new RuntimeException("ChildrenIterator needs a ViewGroup != null to find its children");

   init();
   findChildrenAndAddToList(vg, list);
  }
     
  private void init() {
   list = new ArrayList();
   i = 0;         
  }
     
  @Override
  public boolean hasNext() {
   return ( i < list.size() );
  }
  
  @Override
  public V next() {
   return list.get(i++);
  }
  
  @Override
  public void remove() {
   list.remove(i);
  }
     
  @SuppressWarnings("unchecked")
  private void findChildrenAndAddToList(final ViewGroup root, final ArrayList list) {
   for (int i=0; i < root.getChildCount(); i++) {
    V v = (V)root.getChildAt(i);
    list.add(v);
    if ( v instanceof ViewGroup ) 
     findChildrenAndAddToList((ViewGroup)v, list);
                
   }       
  }
 } 
}

And the styles (put in an XML file under the 'res/values' folder):



 
 
 
 
    
 
 
 
 
 #88FF0000
 #880000FF
 #88FFFF00
 #88995f86
 #aaffbf00
 #88ff33cc
 #0000

Notes on Android SQLite bulk insert

2010-07-25T21:46:00.000-07:00

There's no real bulk insert in SQLite I'm aware of to date. I've tried various ways to insert data fast into Android's SQLite DB, and here are my notes:
1. Use transactions. (e.g. db.beginTransaction, etc..).
2. Use compiled statement: db.compileStatement(insertStatementString), it's much faster than db.insert().

So, in short:


db.beginTransaction();
try {
    string sql = "insert into products (id) values (?)";
    SQLiteStatement insert = db.compileStatement(sql);

    for (.....) {
        insert.bindLong(1, 12345);
        insert.executeInsert();
    }
    db.setTransactionSuccessful();
} finally {
    db.endTransaction();
}

ASP.NET error: Object Expected / ScriptResource.axd

2010-07-20T00:51:00.000-07:00

What this error means in plain English: JavaScript error.

The following case is how I solved a specific error in ASP.NET. It might give you ideas how to solve similar issues of ("Object Expected" with ScriptResource.axd). The easiest way to solve it is to use Firefox & firebug to trace down the specific JavaScript line which cause the problem.

In the scenario bellow a resource (JavaScript) could not be loaded by the browser because the clock on the computer was set back in time. This caused this problem in another JavaScript (missing definition) which caused the error message to pop-up.

Step by step how I traced down the problem:
1. When running an ASP.NET site with Menu item I got the "Object expected" error with the following information: "ScriptResource.axd". When I clicked the detailed information it gave me the URL of the resource which cause the problem.

Bottom line:
* This error is a result of an unspecified JavaScript Error which accrued during running of a JavaScript file embedded in an ASP.NET project.
* Verify you can open the JavaScript URL using the browser.
* Debug the page using Firebug (on Firefox), see (2)

2. When opening the page in Firefox with Firebug and setting the Firebug "console" to "enabled" (with "Show JavaScript errors") it caught the following exception:
"WebForm_GetElementByTagName is not defined"

The function "WebForm_GetElementByTagName" is declared in an embedded resource called: "WebForms.js", which is in many cases the first Java script included in an HTML generated by an ASP.NET page.

Searching about this error online yielded only the following result:
http://forums.asp.net/p/1439101/3253854.aspx

Buttom line:
* Try to open in the browser each and every JavaScript include files (.AXD) in the page.

3. The error I got when I've tried to open the first ".AXD" JavaScript include file was - Parameter: "utmDate" out of range/out of date - which basically pointed me to check the computer date, since I've taken it back in time.

Setting the date forward again fixed my problem.

Combo box / Drop down list box in Android

2010-07-18T04:03:00.000-07:00

As usual doing something simple in Android is frustrating - this time: a simple Combo (or DropDownList). The little and important tweak - calling "setDropDownViewResource" to set the style of the items in the dialog box.

XML:
<spinner id="@+id/spinner" layout_width="wrap_content" android:layout_height="wrap_content" />

Code to add the data:


Spinner spinner = (Spinner)this.findViewById(R.id.spinner);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(
        this,
        android.R.layout.simple_spinner_item,
        new String[] { "1", "2", "3" });
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinner.setAdapter(adapter);

A common task is to populate a spinner using a string array defined in a resource file. Here's a function which do just that:


 public static void populateSpinnerWithArray(Spinner spinner, int stringArrayResId) {
     ArrayAdapter<String> adapter = new ArrayAdapter<String>(
             spinner.getContext(),  
             android.R.layout.simple_spinner_item,
             spinner.getContext().getResources().getStringArray(stringArrayResId));  
     adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);  
     spinner.setAdapter(adapter);  
 }

App crash when setting layout_weight without layout_width

2010-07-18T03:57:00.000-07:00

While playing with the layout on Android I encountered the following weird problem: when using "android:layout_weight" attribute for an element without "android:layout_width" attribute it works just fine in the emulator but on the real phone it crash (Nexus One, Android 2.2).

Since using "android:layout_width" gives me unwanted results I've tried to work around this issue and found the following solution:
android:layout_width="0dip"

Displaying a simple message box in Android

2010-07-08T00:06:00.000-07:00

There are 2 options to display a pop-up in Android (both are not blocking):
Toast - display a short balloon pop-up that will disappear after few seconds
AlertDialog - display a pop-up window with buttons.

Toast:


Toast.makeText(this, "Hello World", Toast.LENGTH_SHORT).show();

AlertDialog:


AlertDialog ad = new AlertDialog.Builder(this).create();
ad.setCancelable(false); // This blocks the 'BACK' button
ad.setMessage("Hello World");
ad.setButton("OK", new DialogInterface.OnClickListener() {
    @Override
    public void onClick(DialogInterface dialog, int which) {
        dialog.dismiss();                    
    }
});
ad.show();

Note: it's better to use "this.getString(R.string.ok)" and get the string from a resource file.

Android Debug.startMethodTracing() failed

2010-07-04T07:58:00.001-07:00

With the following exception: "file open failed".

Reason: No SD card write permission was given to the application (Android 1.6+)
Solution: Make sure you add the permission to the Manifest file -

Setting Android volume programmatically to maximum

2010-07-02T05:39:00.000-07:00

I searched a bit how to the volume of an Android application to maximum, and I saw few post regarding people asking about MediaPlayer.setValue function.

It's not the right function for setting the volume (see the help).
To set the volume to maximum (or any relative value):

// Get the AudioManager
AudioManager audioManager =
(AudioManager)this.getSystemService(Context.AUDIO_SERVICE);
// Set the volume of played media to maximum.
audioManager.setStreamVolume (
AudioManager.STREAM_MUSIC,
audioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC),
0);

Polishing Android application

2010-06-22T22:41:00.000-07:00

Before deployment of an Android application there are few common steps that you should consider to ensure the application has a professional look:

Add an EULA - See here how.
Set the correct sound control - Android has multiple sound controls (alarm volume, sound volume, phone volume etc.). You should me sure that when the user click on the volume buttons the correct volume is set (See here how). For example, to set the volume button to control the media volume:
this.setVolumeControlStream(AudioManager.STREAM_MUSIC);
Disable buttons that are not in use - Except the "Home" buttons, all other buttons can be disabled by overriding "onKeyDown" function.
Hide the window title bar & the Android status bar - To hide the status bar:
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN)
To hide the window title:
requestWindowFeature(Window.FEATURE_NO_TITLE);

Android app requires un-needed permissions

2010-06-21T12:10:00.000-07:00

After finishing writing Android app, during installation the application request permissions for:
* Storage
* Phone calls

However those permissions are not requested in the AndroidManifest.

Solution:
This is a backward compatibility issue with Android 1.5 or less. Just add: android:targetSdkVersion="4" to the uses-sdk tag, for example:

(you must compile the application with platform SDK 1.6 or later).

Project wouldn't run after importing to Eclipse

2010-06-16T00:28:00.001-07:00

With the following error message:
"The selection cannot be launched, and there are no recent launches"

I got it for my Android project, but it's not limited to android.
Since I'm newbie to Eclipse I started to googling but I couldn't find a solution. Playing with the UI got me to the right place:

In the main menu: "Run" -> "Run configurations..."
Double click the project type you want (in my case "Android Application") & select the project you want to run.

How to delete VPN or Dail-up connection in Windows 7

2010-06-03T22:59:00.000-07:00

It took me a while to find out how to delete a VPN connection I've setup on Windows 7.

So here's how:
1. Click on the connection icon in the icon tray (right-bottom side of the screen)
2. Click on "Open Network and Sharing Center" (you can open it also from the Control Panel)
3. On the left side of the window, click on "Change adapter settings"
4. Delete the VPN/Dail-up

SharePoint web part deployment error: Object reference not set to an instance of an object error

2010-06-02T00:52:00.000-07:00

After deploying a SharePoint web-part developed using VSeWSS I get:
"Object reference not set to an instance of an object error"

Solution: copy the web part DLL to the GAC (it's also possible to register the DLL to the GAC on the batch file 'setup.bat' created by VSeWSS by calling gacutil.exe).

Exception: Error executing child request for ChartImg.axd

2010-05-31T04:02:00.000-07:00

I got this exception when I used the charts built-in to .NET 3.5. The scenario in which I got this exception was only when the charts first appeared after postback.

Solution: In the web.config file add 'POST' to the DataVisualization verbs:
The old syntax:
<add path="ChartImg.axd" verb="GET,HEAD" type="System.Web.UI.DataVisualization.Charting.ChartHttpHandler, System.Web.DataVisualization, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
validate="false" />

The new syntax:
<add path="ChartImg.axd" verb="GET,HEAD,POST" type="System.Web.UI.DataVisualization.Charting.ChartHttpHandler, System.Web.DataVisualization, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
validate="false" />

Android SDK Error: Unable to resolve target 'android-X'

2010-05-11T08:55:00.000-07:00

There are few variants of this error message:
Unable to resolve target 'android-1'
Unable to resolve target 'android-2'
Unable to resolve target 'android-3'
Unable to resolve target 'android-4'
Unable to resolve target 'android-5'
Unable to resolve target 'android-6'
Unable to resolve target 'android-7'
Unable to resolve target 'android-8'
Unable to resolve target 'android-9'
Unable to resolve target 'android-10'
Unable to resolve target 'android-11'
Unable to resolve target 'android-12'
Unable to resolve target 'android-13'
Unable to resolve target 'android-14'
Unable to resolve target 'android-15'

Reason: Could not find the proper Android SDK version. If the android SDK is installed correctly the problem is that the platform SDK requested by the "default.properties" is not installed. For example:
Unable to resolve target 'android-1' - (Android 1.0) change the "default.properties"
Unable to resolve target 'android-2' - (Android 1.1) change the "default.properties"
Unable to resolve target 'android-3' - install SDK Platform Android 1.5
Unable to resolve target 'android-4' - install SDK Platform Android 1.6
Unable to resolve target 'android-5' - install SDK Platform Android 2.0
Unable to resolve target 'android-6' - install SDK Platform Android 2.0.1
Unable to resolve target 'android-7' - install SDK Platform Android 2.1
Unable to resolve target 'android-8' - install SDK Platform Android 2.2
Unable to resolve target 'android-9' - install SDK Platform Android 2.3
Unable to resolve target 'android-10' - install SDK Platform Android 2.3.3
Unable to resolve target 'android-11' - install SDK Platform Android 3.0
Unable to resolve target 'android-12' - install SDK Platform Android 3.1
Unable to resolve target 'android-13' - install SDK Platform Android 3.2
Unable to resolve target 'android-14' - install SDK Platform Android 4.0
Unable to resolve target 'android-15' - install SDK Platform Android 4.0.3

You can do this using the Android SDK Setup utility:
Option 1: Eclipse -
"Windows" \ "Android SDK and AVD Manager" \ "Available packages"

Option 2: Command line - start the "SDK Setup" here (x86):
C:\Program Files\Google\Android SDK\SDK Setup.exe
or here (x64)
C:\Program Files (x86)\Google\Android SDK\SDK Setup.exe

GoDaddy windows hosting with WordPress Permalinks

2010-04-11T03:31:00.000-07:00

After moving multiple domains hosted in GoDaddy to a single Delux windows account I found out that the WordPress permalinks (e.g. SEO nice URL) aren't working anymore.

There are multiple discussions online regarding this problem, mostly regarding redirecting the 404 error page. However the solution is SUPER simple - RTFM (the following answer appears in the WordPress permalink setting page): add a file "web.config" containing the following lines


<?xml version="1.0"?>
<configuration>
  <system.webServer>
    <rewrite>
      <rules>
        <rule name="Main Rule" stopProcessing="true">
          <match url=".*" />
          <conditions logicalGrouping="MatchAll">
            <add input="{REQUEST_FILENAME}" matchType="IsFile" negate="true" />
            <add input="{REQUEST_FILENAME}" matchType="IsDirectory" negate="true" />
          </conditions>
          <action type="Rewrite" url="index.php" />
        </rule>
      </rules>
    </rewrite>
  </system.webServer>
</configuration>

Twitter statistics: Avg. number of follower by time zone

2010-04-10T23:45:00.000-07:00

About a week ago I saw this post on TechCrunch and I wondered what other irrelevant statistics I can find on Twitter (given the fact I've already put some time in collecting and parsing Twitter data).

Here is the number of followers by time zone settings (removed time zones with less than 10,000 users, sorry Sydney).

Minimal analysis:

Greenland - More people set their time zone to Greenland than the population there...
Alska - Over 6% (!) of the population are tweeting [see also - 'Greenland'].
Tokyo - Don't set your time zone to Tokyo if you want people to listen to you, lot's of people are tweeting from Tokyo but no one listens.
No Time Zone - There's a very low followers count for people with no time zone setting - I guess the reason is that those people are new to Twitter or just don't care enough (those people are about 20% of this entire sample).

Data collected from the Twitter Sampling API, March 21st-25th, 2010.
Total number of users visible during that time frame: 2.5M (which is a very nice sample).

Parsing Twitter JSON: Comparing C# libraries performance

2010-03-27T01:29:00.000-07:00

Twitter stream API return the data in JSON format. There are multiple JSON libraries in C#, however since I wanted to parse large volumes of data I did a short performance test to see which library gives the best performance in parsing Twitter JSON data.

The libraries tested:
* Json.NET - A popular C# JSON library.
* Gapi.NET - Gapi.NET is not a JSON parsing library, but it contains JSON parsing routines.
* Procurios - Yet another C# JSON library. See also this blog post how to use it to parse Twiter data.
* JavaScriptSerializer - .NET 3.5 built-in JSON parser.
* DataContractJsonSerializer - .NET 3.5 built-in JSON parser.
* AjaxPro - A C# AJAX library.

Results:

The test:
* Data: Twitter Stream API sampling interface data for one hour (2PM GMT) during Match 24th 2010. File size is 285Mb, contains 208,530 lines, one JSON object per line.
* Computer: HP Pavillion DV6000, Intel T9300 2.5GHz, 4GB Memory running Windows 7 x64
* Software: with each library I've performed a very simple test - parse all the messages & get the 'text' field data of every message, if it exists (see code below).

Results:
* Json.NET - 12 seconds, no errors.
* Gapi.NET - 10 seconds, no errors.
* Procurios - 35 seconds, 207 errors.
* JavaScriptSerializer - 77 seconds, no errors.
* DataContractJsonSerializer - 24 seconds, 7452 errors (all the JSON objects that did not contain 'text' element).
* AjaxPro - 16 seconds, no errors.

Code:
Here's the code used for parsing a single line in each of the libraries. Variable line contains a JSON object, the extracted tweet is stored in the variable text.

Json.NET parsing code


Dictionary jsonObjects = new Dictionary();
StringReader lineReader = new StringReader(line);
using (Newtonsoft.Json.JsonTextReader jsonReader =
new Newtonsoft.Json.JsonTextReader(lineReader))
{
while (jsonReader.Read())
{
if ((jsonReader.ValueType != null) && (jsonReader.Depth == 1))
{
 string key = jsonReader.Value.ToString();
 jsonReader.Read();
 jsonObjects.Add(key, jsonReader.Value);
}
}
}

object textObject;
if (jsonObjects.TryGetValue("text", out textObject) == true)
text = textObject.ToString();

Gapi.NET parsing code


Gapi.Json.JsonObject jsonLine = Gapi.Json.JsonObject.Parse(line);
Gapi.Json.JsonValue textValue;
if (jsonLine.TryGetValue("text", out textValue) == true)
text = textValue.ToString();

Procurios parsing code


Hashtable jsonHash = (Hashtable)Procurios.Public.JSON.JsonDecode(line);
text = jsonHash["text"] as string;

JavaScriptSerializer


public class TwitterJsonObject
{
public string text;
}


JavaScriptSerializer jSerialize = new JavaScriptSerializer();
TwitterJsonObject twitterJsonObject = jSerialize.Deserialize<twitterjsonobject>(line);
text = twitterJsonObject.text;

DataContractJsonSerializer


// This line is executed once
DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(TwitterJsonObject));

// This code is executed for every JSON object
MemoryStream ms = new MemoryStream(Encoding.Unicode.GetBytes(line));
TwitterJsonObject twitterJsonObject = ser.ReadObject(ms) as TwitterJsonObject;
text = twitterJsonObject.text;

AjaxPro


TwitterJsonObject twitterJsonObject = AjaxPro.JavaScriptDeserializer.DeserializeFromJson(line, typeof(TwitterJsonObject)) as TwitterJsonObject;
text = twitterJsonObject.text;

DoDragDrop prevents DoubleClick event from firing

2010-03-25T03:48:00.000-07:00

I've tried implementing Drag & Drop in a ListView object, however, calling DoDragDrop from either MouseMove or MouseDown prevented DoubleClick event from firing.

There are few posts online about it, mostly saying using MouseDown event and checking:
e.Clicks == 1
(see for example: here)

However this didn't work for me (DoubleClick fired some times, but most of the time it didn't). After doing further research I came with the following full solution:


bool _beginDragDrop = false;

void ListViewBase_MouseMove(object sender, MouseEventArgs e)
{
 if ((e.Button == MouseButtons.Left)&&(_beginDragDrop == true))
 {
  // Replace this with the object you want to Drag & Drop
  object draggedObject = this;
  this.DoDragDrop(draggedObject, DragDropEffects.Copy);
 }
}

void ListViewBase_MouseDown(object sender, MouseEventArgs e)
{
 if ((e.Button == MouseButtons.Left) && (e.Clicks == 1))
  _beginDragDrop = true;
 else
  _beginDragDrop = false;
}

AjaxToolkit: TabContainer not visible after setting TabPanel.Visible = false

2010-02-22T08:53:00.000-08:00

After upgrading AjaxToolkit I had the following weird problem: a TabContainer disappeared.

A short investigation showed that it was cause because I was setting a TabPanel property
tabPanel.Visible = false

Bottom line: If you set the ActiveTab of the TabContainer to Visible=false => the TabContainer will not be drawn. I'm not sure if it's a bug or a feature.

Resolution: Change the ActiveTab when you set TabPanel.Visible = false

Error 2869 during installation

2010-02-10T09:13:00.000-08:00

The problem:
Error message during installation on Windows Vista / 7:
The installer encountered an unexpected error installing this package. This may indicate a problem with the package. The error code is 2869.

Reason:
The MSI contains a custom action that require more privileges than the current user have.
Due to UAC (user access control) even if you're administrator, you're not REALLY administrator unless specifically run as such.

Resolution:
- Simple option - Install as administrator.
- If you wrote the package in Visual Studio 2005/2008 add the following to require administrator privileges to begin installation:
1. Right click on the setup project -> View -> Launch Conditions
2. In the Launch conditions window, right-click the node "Launch Conditions" and select "Add launch condition".
3. Rename the new launch condition to something like "Require Administrator".
4. In the new launch condition property window set "Condition" to "AdminUser"
5. Set the error message to something meaningful ("Only administrator can install this software").
6. Check the following post & add "NoImpersonate.js"
7. Rebuild the package.

MAPIInitialize fails with code 0x80010106 in C#

2010-01-28T02:07:00.000-08:00

I've tried to use MAPI in C# but MAPIInitialize keeped on failing with error code: 0x80010106.

The clue I found only is that this error code is related to multi-threading.
The answer was simple - set the application attribute:
[STAThread]

WinSNMP C# wrapper fails in 64 bit systems

2010-01-21T00:55:00.000-08:00

Some time ago I wrote a C# wrapper for WinSNMP. Recently I moved to Win7 64 bit and that application failed to run. I thought it's because of Win32 API change, but it seems like the issue was with 32 bit vs. 64 bit.

Solution: (work-around) compile the application to x32:
Right click the project -> Build -> Platform Target -> x86

It could be that I did something wrong in the wrapper, but I really don't have the time to check it out.

Convert SQL Server Database to Access MDB

2010-01-10T23:44:00.000-08:00

I tried looking around the web how to accomplish the following task:
Convert SQL Server Database to Access MDB

I couldn't find any answer online, but on the way to work it hit me: use SQL Server Management Studio "Export". I just checked it and it works like a charm. In 2 minutes I was able to export the SQL Server database to Access MDB.

Just do:
1. Open SQL Server Management Studio & connect to the SQL Server database.
2. Right click the database and select - "Tasks" => "Export"
3. Select the source database & select Access MDB as destination.
Continue with the instructions.

TFS Error: HTTP code 403: TF53011: DOMAIN\USER is not a licensed user.

2009-12-15T01:05:00.001-08:00

While adding a new user to the TFS I got the following error:
HTTP code 403: TF53011: DOMAIN\USER is not a licensed user.

There are many talks in the web, but the solution might be VERY simple (it was in my case):
Add the new user to the TFS group "Team Foundation Licensed Users Group":
- In the 'Team Explorer', right click on the TFS Server -> Team Project Settings -> Group Membership
- Add the new user to the following group:
[SERVER]\Team Foundation Licensed Users Group

Scheduled Task fails: Could not start

2009-11-22T06:59:00.000-08:00

I just got a new machine for a customer and started to set it up. I've defined multiple scheduled tasks, and I got: "Could not start" error for one of the tasks... That specific task was a batch job.

I've found few resources on the web and solved the problem. I would recommend the following protocol for such an error:
*. Check the log file of the scheduled tasks: open the scheduled tasks in explorer window and select "Advanced"->"View Log".

Option 1:
*. Check the following policy: Control Panel|Admin Tools|Local Security Policy\Local Policies\User Rights Assignments "Log on as a batch job" (also - someone wrote that his problem was that there was a group policy overriding the local computer policy).

Option 2:
If the error is:
0x80070005: Access is denied.
Try using the Task page Browse button to locate the application.

Try resolving it using the protocol defined here:
*. Check the user you are trying to run as can run the script:
---- Start - Run - RunAs /user:username@domain (Your Command)
*. If it doesn't run, try giving the user privileges:
Cacls c:\windows\system32\cmd.exe /e /g username@domain:r

Open a new browser tab from ASP.NET control

2009-10-27T00:35:00.000-07:00

To open a new browser tab from ASP.NET control client side scripting must be used (not ASP.NET OnClick). There are few answers on the web how to do that. Some don't work & some are incomplete. The following works with any browser version I've checked:

button.Attributes.Add("onclick", "javascript: window.open('your_url','',''); return false;");

This add a client side event handler "onclick", which overrides the ASP.NET OnClick event. If you put both ASP.NET OnClick event handler & this "onlick" client side handler, only the client side will be executed. You may choose if to add the client side handler at run-time.

Configuring Option GlobeSurfer II

2009-09-05T11:58:00.001-07:00

For some reason it's hard to find some configurations in this router, here goes for what I needed:
Port Forwarding: Connection Settings -> Security -> Port Forwarding
Static Addresses: Advanced -> IP Address Distribution -> Connection List

SharePoint writes 'Unknown Error'

2009-08-26T08:22:00.000-07:00

The following post was very helpful:
http://koenvosters.wordpress.com/2009/08/06/showing-the-real-error-message-in-sharepoint/ - It Shows how to set the IIS to display the full stack trace.

ASP.NET Error: The resource cannot be found

2009-08-24T00:29:00.000-07:00

Check the following:

1. Check that the target resource exists.

2. Check that ASP.NET is enabled on the IIS:
A. Open: Administrative Tools => Internet Information Service (IIS) Manager
B. Expand the server, click on 'Web Service Extension'
C. Verify that ASP.NET is set as 'Allowed'. If not, change it.

Using multiple JavaScript libraries (Prototype, MooTools, jQuery)

2009-08-16T23:30:00.000-07:00

I'm a fan of MooTools (a JavaScript library), and most of the tools I use are based on this library. That said, one of the best JS around is LightBox, which is based on Prototype. However, when I tried using both MooTools & Prototype libraries in the same webpage it failed. I was sure there's a solution so I kept digging in, but I couldn't find any.

Another JS library - jQuery has a special computability function called noConflict which solves those problems, but both MooTools & Prototype lack that functionality.

The only solution I could find: Choose one library - MooTools or Prototype, and use only that library. There are similar implementation of most tools in both libraries.

Cannot resolve the collation conflict between XXXXXXX and YYYYYYYYY in the equal to operation

2009-07-19T00:09:00.000-07:00

This error indicated that the strings in the join operation are from fields created in different collation. In general, it's better to recreate the fields with the same collation definition, but if you're just too lazy, and want to get things done, just cast to problematic field (in this example it's to 'SQL_Latin1_General_CP1_CI_AS'):

SELECT *
FROM A, B
WHERE A.F1 = B.F1 COLLATE SQL_Latin1_General_CP1_CI_AS

WordPress & GoDaddy Windows shared hosting

2009-07-13T12:50:00.000-07:00

Wordpress works just fine in GoDaddy shared Windows hosting (IIS7), however when trying to install a plugin I get:

Downloading install package from http://downloads.wordpress.org/plugin/XXXXXX.zip.

Warning: touch() [function.touch]: Unable to create file D:\Hosting\XXXXX\html\XXXXXX.com\blog/wp-content/XXXXXX.zip because Permission denied in D:\Hosting\2804923\html\spassets.com\blog\wp-admin\includes\file.php on line 175

Download failed. Could not create Temporary file

Solution: since no solution can be found on the web, I used the good old method - manual install:
* Download the package from wordpress
* Uncompress and upload to /wp-content/plugins (I just copied from another wordpress I have).

And it works!

Web.config & GoDaddy.com

2009-07-12T05:45:00.001-07:00

I wrote a small ASP.NET application, which needed to read the web.config file. To open the Web.config file I used 'OpenWebConfiguration':
WebConfigurationManager.OpenWebConfiguration(...)

Since GoDaddy uses medium trust, I kept on getting:
'The application attempted to perform an operation not allowed by the security policy'

And in the detailed:
'System.Security.SecurityException: Request for the permission of type 'System.Security.Permissions.FileIOPermission, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.

The resolution - use ConfigurationManager.ConnectionStrings instead.

Pre-selecting items from CheckBoxList

2009-06-29T07:36:00.000-07:00

I'm not much of an ASP.NET guy, but from time to time I've got to write some simple ASP.NET pages.

I've tried to use data-bound CheckBoxList (data binding done with the built-in wizard), and update the data with some pre-selected values. For some reason CheckBoxList Items are not populated when Page_Load function is called, so the list can't be updated.

Solution A: Found it on Google, but should have thought about it myself - just remove the data-binding done with the VS wizard, and do all the data handling in code.

Solution B (better): Call 'DataBind()' before pre-selecting the CheckBoxList items.

Weird. I must be missing something here. Anyway - it's working.

Generics Dictionary<> clone

2009-06-23T01:00:00.000-07:00

Here's a simple routine that will clone generic Dictionary:


public static Dictionary<S, V> Clone<S,V>(Dictionary<S, V> dictionary)
{
 Dictionary<S, V> cloneDictionary = new Dictionary<S, V>();
 foreach (KeyValuePair<S, V> kvp in dictionary)
   cloneDictionary.Add(kvp.Key, kvp.Value);

 return cloneDictionary;
}

SharePoint Web-part dev problem - List does not exist

2009-05-20T21:56:00.000-07:00

Problem:
I was working on a web-part with a custom ASPX file. It was working just fine for the root site of a site collection, but when testing it on a subsite it failed to load the ASPX file with the following exception:

List does not exist

The page you selected contains a list that does not exist. It may have been deleted by another user.

Solution:
There are few suggestions that didn't help me on the web. With the good old method - remove everything and check what's making the problem I found the perpetrator: in the ASPX page, I used SharePoint:FormattedStringWithListType, which caused the exception.

Using reflector I found that FormattedStringWithListType has a property 'List' which opens SPList with the current SPWeb context (list GUID is taken from the request parameter named 'List'). At this point I noticed that when the ASPX file is opened, it is done from the site collection level & not the sub site level.

From here there are few possible solutions:
*. Open the ASPX file from the subsite level (probably the best solution).
*. Don't use the class FormattedStringWithListType
*. Copy with reflector & fix the problem using SPSite.

Response.Header.Add doesn't work

2009-03-28T03:31:00.000-07:00

I've tried to use:
Response.Header.Add("HeaderKeyName", "KeyValue")

But I got the following exception:
System.PlatformNotSupportedException: This operation requires IIS integrated pipeline mode.
at System.Web.HttpResponse.get_Headers()

The work around:
Response.AddHeader("HeaderKeyName", "KeyValue")

For the least Microsoft could find a better exception description.

HyperLinkField not showing as link (ASP.NET)

2009-03-24T07:54:00.000-07:00

After binding data to a HyperLinkField in a GridView it didn't show as link but as a normal text. Apparently when using navigation by data fields, the data in the fields set in DataNavigateUrlFields must be validated.

See some more information here:
http://stackoverflow.com/questions/640120/hyperlinkfield-not-showing-as-link

I had a problem when the field was a DateTime field returned by a database query. I've change the field format in the following way to make this work (navigation):
[Date] = convert(VARCHAR, [Date],104)

You are not authorized to view this page

2009-03-10T05:01:00.000-07:00

Symptoms:

One clear morning, on an operational system (Windows 2003 x64, IIS, ASP.NET, SQL Server 2005) running an ASP.NET application, the users started to get request to fill their credentials, and after few times they got:

You are not authorized to view this page

With more specific notification:

HTTP Error 401.1 - Unauthorized: Access is denied due to invalid credentials.Internet Information Services (IIS)

In the event log of the server I found the following errors:

- System Events - I found warning event 1011 titled "W3SVC":
A process serving application pool 'DefaultAppPool' suffered a fatal communication error with the World Wide Web Publishing Service. The process id was '6756'. The data field contains the error number.

- Application Events - I found error event 1000 titled ".NET Runtime 2.0 Error Reporting":
Faulting application w3wp.exe, version 6.0.3790.3959, stamp 45d691cc, faulting module kernel32.dll, version 5.2.3790.4062, stamp 462643a7, debug? 0, fault address 0x0000000000027d8d.

Resolution:

I followed few wrong leads on the web, such as:

- Permissions issue: http://support.microsoft.com/kb/918041/en-us

- SQL Server serface issue: http://www.sqlnewsgroups.net/group/microsoft.public.sqlserver.server/topic20191.aspx

After wasting nearly a day a found the root cause:
The ASP.NET application had a stack-overflow bug.

From here fixing is easy.

The reason that I didn't suspected the ASP.NET application was that the stack-overflow bug was caused by a run time change of the data in the application, and not something new installed/configured.

How to check if the Laptop IR (Infrared) is working

2009-01-26T04:44:00.000-08:00

This is really cool - open your Cellular phone camera and point it to the laptop IR sensor. The sensor will blink every 3-4 seconds on the cellular camera screen.

I've been told it also works with remote controls (so you can check the batteries), and I can only guess it's working with any digital camera.

Windows XP drivers for laptops

2009-01-25T06:32:00.000-08:00

As I wrote before I've got HP dv6700 which I've installed win2003 on. Few days ago I've finished the project for which I needed that OS, and I've started to install WinXP on this machine. As I found out HP doesn't really says which drivers I should use for Windows XP. I've tried installing drivers similar to the ones they say for Vista (only WinXP version of them) and they didn't realy want to install...

Anyway, I started to get somewhere only after installing SiSoftware Sandra. An amazing piece of software that just finds out exactly what kind of hardware you got. With this software I found out in minutes which drivers I should use.

WebPart wsp does not include dependent DLLs

2009-01-08T02:16:00.000-08:00

I was trying to develop a webpart for SharePoint 2007 & WSS3 using Windows SharePoint Services 3.0 Tools: Visual Studio 2005 Extensions, Version 1.1.

Everything worked just fine, until I found out that the WSP file created by the add-on does not include dependent DLLs (from other projects in the solution). I could not find any good solution, so finally I had the following options:

1. In post-build event, use ILMerge to merge all the DLLs into a single DLL with the name & key file of the webpart, and replace existing DLL with this new merged DLL.

2. Add the dependent DLL to the project files of the webpart. This way the WSP file includes the dependent DLL. An improvement: add the DLL file in the following directory: bin/Release/ (change the project file with notepad) - this way any new compilation will include the new DLL.

3. Probably the best option - use a 3rd party tool to create the WSP file - WSPBuilder for example.

No audio & 'Unknown PCI Device'

2008-12-18T23:17:00.000-08:00

I've installed a clean Windows XP on a new computer, using the following steps:
1. Windows XP + SP2 + SP3
2. New computer's drivers

However after finishing the audio didn't work, I had 'Unknown PCI Device' listed in my device manager and no audio device in the audio devices list. In the system devices there was no Microsoft AAU device.

I tried many things: check bios settings, update the bios, reinstall RealTek drivers... nothing helped.

The solution I found on one forum stated that there is a problem with Windows XP SP3 HD Audio driver. F**k. Why Microsoft? WHY?

Anyhow, the solution that worked for me:
1. Impersonate to WinXP SP2: Change registry key
"HKLM\SYSTEM\CurrentControlSet\Control\Windows\CSDVersion" value to 200
2. Restart
3. Install HD_Audio/kb888111xpsp2.exe
4. Install RealTek HD Audio driver
5. Restart (and check that the audio is now working)
6. Change the CSDVersion key back to XP SP3 again:
"HKLM\SYSTEM\CurrentControlSet\Control\Windows\CSDVersion" value to 300

Emerging Markets - Definition

2008-12-17T02:11:00.000-08:00

"Emerging markets, definition: Markets you can't emerge from in a crisis", Ron Lubash

Can't install Win 2003/XP: not able to detect hard disk

2008-11-26T04:40:00.000-08:00

I've tried to install Windows 2003 on my HP dv6000, and I got the following error: "not able to detect hard disk".

I found few people with the same problem, but no answer. Only after searching for Windows XP installation issues I found the solution: disable the native SATA support in the BIOS.

Problem: on some computers (including HP dv6000) there's no way to disable native SATA support... grrr...

Bypass: how to add SATA driver to the Windows installation disk see here. (Specifically, HP SATA drivers from my computer found here)

Business Plan

2008-11-26T02:13:00.000-08:00

"Business plans are a branch of science fiction. In classic science fiction the focus is on words, in the business plans the focus is on numbers", Yossi Vardi

"Business plan is like a sausage, you'll eat it only if you don't know how it was prepared", Yossi Vardi

GPEH to XML, GPEH Parser

2008-11-18T23:28:00.000-08:00

I was looking around for a GPEH parser, or even GPEH to XML converter but I couldn't find one any where. Anyone?

How to get ERD Commander to boot from USB

2008-10-26T02:11:00.000-07:00

Here's the best resource I've found:
http://forum.xatrix.org/viewtopic.php?f=26&p=9323, however it didn't work for me.

After some tests I found the problem - since I'm using a 4GB USB drive, I had to check the 'LBA' checkbox in the PE2USB application.

Summary:
1. Download PE2UDB
2. Download ERD Commander 2005 & extract the files from the ISO (I use 7zip).
3. Create the USB bootable system using PE2USB:
*** Select destination drive
*** Check 'Enable Disk Format'
*** Set 'Disk Label' to 'CD'
*** Check 'Enable LBA' for USB drives larger than ? (I think 1G).
*** Check 'Enable File Copy' and select the source folder (of the ERD Commander files).
*** Click start

Have fun!

Creating add-ons/toolbars for Google Chrome

2008-09-05T22:50:00.000-07:00

I was looking for information how to write an add-on for Google Chrome, and while looking I couldn't find any information on this subject (the was this calculator JavaScript, but that's not an add-on).

After a while I've decided to try and dig in Chrome's code, however, even before doing that I found the answer in the Google Code repository of Chrome:

Q. How can I develop extensions for Chromium like in Firefox?
A. Chromium doesn't have an extension system yet. This is something we're interested in adding in a future version. Note that Chromium does support NPAPI-style "plugins", such as Adobe Flash and Apple QuickTime.

See the original FAQ here

Fixed aspect ratio in C# window

2008-09-03T01:11:00.000-07:00

I needed to create a window with a fixed aspect ratio (for video), and I wanted that the resize frame will change with the user cursor drag.

I came around with this post. Which is almost perfect, but when you drag the left or upper bounds you get the window moving... Here is the fixed code:


#region Keep video window aspect ratio
[StructLayout(LayoutKind.Sequential)]
public struct RECT
{
    public int Left;
    public int Top;
    public int Right;
    public int Bottom;
}

public class MyRect
{
    public int Left;
    public int Top;
    public int Right;
    public int Bottom;
}

public const int WM_SIZING = 0x0214;
int _lastWidth = 0;
MyRect _lastRect = null;
double _aspectRatio = 0.5;

protected override void WndProc(ref Message m)
{
    if (m.Msg == WM_SIZING)
    {
        RECT rc;
        rc = (RECT)Marshal.PtrToStructure(m.LParam, typeof(RECT));

        if (_lastRect == null)
        {
            _lastRect = new MyRect();
            _lastRect.Top = rc.Top;
            _lastRect.Bottom = rc.Bottom;
            _lastRect.Left = rc.Left ;
            _lastRect.Right = rc.Right;
        }

        if (rc.Right - rc.Left != _lastWidth)
        {
            double newHeight = ((double)(rc.Right - rc.Left)) 
                                   / _aspectRatio;
            rc.Bottom = (int)newHeight + _lastRect.Top;
            Marshal.StructureToPtr(rc, m.LParam, true);
        }
        else
        {
            double newWidth = ((double)(rc.Bottom - rc.Top)) 
                                  * _aspectRatio;

            rc.Right = (int)newWidth + _lastRect.Left;
            Marshal.StructureToPtr(rc, m.LParam, true);
        }

        _lastWidth = rc.Right - rc.Left;
        _lastRect.Top = rc.Top;
        _lastRect.Bottom = rc.Bottom;
        _lastRect.Left = rc.Left;
        _lastRect.Right = rc.Right;
    }

    base.WndProc(ref m);
}
#endregion

Deleting locked VSP files

2008-07-06T01:35:00.000-07:00

Few days ago I found huge VSP files on one of my servers. I found out that those files are temporary files of a symantec backup software. For some reason, from time to time the backup application does not delete it's temporary files.

When I tried to delete the files I couldn't do it - "File is used by another process" or something like that.

DISCLAIMER: Do the following procedure on your own risk. The writer of this blog takes zero (0) responsibility.

To bypass it I used the procedure to delete locked files (without restart):
1. Start Process Explorer by Microsoft/SysInternals(no need for installation, just copy the EXE file to the target machine).
2. Make sure the lower panel is visible: View -> Lower Pane View -> Handles
3. In the process tree select "System"
4. Sort the lower pane by Name, and find the VSP file lock (since the pane is sorted by name, it should be easy to find it by 'e:\WhatEverFileName.vsp')
5. Right-click the record in the lower pane and select "Close Handle".
6. Delete the file.

int.Parse throws FormatException without a reason

2008-04-17T03:13:00.000-07:00

For few days I've tried to debug a client's problem - int.Parse kept on throwing FormatException when everything was OK.

Finally I found this post, which says - check the regional settings:
Registry: HKEY_CURRENT_USER\Control Panel\International
Key: sPositiveSign (and the negative one).

My client checked both and they were just fine, but I've decided to write my own int.Parse which does this following:

if (str == "0")
return 0;
else
return int.Parse(str);

This fixed everything (I did the same for double.Parse too).

Hiding/disabling UpdatePanel during update

2008-04-04T23:35:00.000-07:00

One of the most common tasks in AJAX is disabling UpdatePanel during AJAX call, i.e:

I expected UpdateProgress to do just that. It doesn't. I searched to web but I only found patches that forced using JavaScript with-in my pages.

Finally I found this (from which I took the image above):
http://www.codeplex.com/FlanAjaxControls

Open source, Ajax.Net only extender, that lets you disable the UpdatePanel and display the UpdateProgress over the disabled control during the update. No JavaScript, just add the control and CSS style.