Set Alpha/Opacity of Layout of widget
===

I want to set the opacity of background of `LinearLayout`, I found this [solution][1] that works fine if I use normal layouts, but in the case of `android-widgets` we have to set layout different I wrote the following code 

    public class AlphaLayout extends LinearLayout {

	public AlphaLayout (Context context) {
		super(context);
		// TODO Auto-generated constructor stub
	}

	public AlphaLayout (Context context, AttributeSet attrs) {
		super(context, attrs);
		// TODO Auto-generated constructor stub
	}

	@Override
	protected void onAnimationStart() {
		AlphaAnimation alphax = new AlphaAnimation(0.5F, 0.5F);
		alphax.setDuration(0);
		alphax.setFillAfter(true);
		this.startAnimation(alphax);
		super.onAnimationStart();
	}

}


And my corresponding widget xml layout is

    <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="@dimen/widget_margin" >

    <com.exercise.HelloWidget.AlphaLayout 
        android:id="@+id/myWidgetLayout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_gravity="center"
        android:background="@drawable/appwidget_dark_bg"
        android:orientation="horizontal" >
        <TextView
            android:id="@+id/song_info"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:layout_marginLeft="10dp"
            android:layout_marginRight="10dp"
            android:layout_marginTop="10dp"
            android:text="Hello"
            android:textAppearance="?android:attr/textAppearanceLarge"
            android:textColor="@color/white" />

        <TextView
            android:id="@+id/timeWidget"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:layout_marginLeft="10dp"
            android:layout_marginTop="10dp"
            android:text="03:30"
            android:textAppearance="?android:attr/textAppearanceLarge"
            android:textColor="@color/white" />

        
       
    </com.exercise.HelloWidget.AlphaLayout>

</FrameLayout>


after running the project When I add a widget to my homescreen, its displaying an error `Problem loading widget`

Can you tell me what I am doing wrong ? Your help will be appreciated.
  [1]: http://stackoverflow.com/questions/4813995/set-alpha-opacity-of-layout