Android: Set match_parent in custom view programmatically

I have implemented a custom view in which I can draw. I want to set it to MATCH_PARENT so that it fills the screen regardless of the screen orientation. When I change orientation to landscape, it only fills 50% of the width.

I changed onMeasure () but there was no effect:

public class DrawScreen extends View{

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);   
    if(context.getResources().getConfiguration().orientation==Configuration.ORIENTATION_LANDSCAPE){
        setMeasuredDimension(screenWidth, screenHeight);
    }else{
        setMeasuredDimension(screenHeight, screenWidth);
    }

}
}


public class MyService extends Service{

...
windowManager.addView(toolbox, params);
}