glow when touch the screen in android?

Question

when i touch whereever in the screen that point will be glow(nothing but like a flash or glittering) for some time. how to do that? any example or idea?? i have to implement to put buttons on it. exactly when i touch the screen it will glow some time and then the button will appear on the point where i touched.

Answer 1

Your going to have to create a custom view and override ontouchevent and draw. Here's a very simple example. you can reference a custom view in an xml layout if you use the package name i.e. com.test.CustomView.

public class CustomView extends ImageView{
public CustomView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
}
public CustomView(Context context, AttributeSet attrs) {
    super(context, attrs);
}
public CustomView(Context context) {
    super(context);
}
boolean drawGlow = false;
//this is the pixel coordinates of the screen
float glowX = 0;
float glowY = 0;
//this is the radius of the circle we are drawing
float radius = 20;
//this is the paint object which specifies the color and alpha level 
//of the circle we draw
Paint paint = new Paint();
{
    paint.setAntiAlias(true);
    paint.setColor(Color.WHITE);
    paint.setAlpha(50);
};

@Override
public void draw(Canvas canvas){
    super.draw(canvas);
    if(drawGlow)
        canvas.drawCircle(glowX, glowY, radius, paint);
}
@Override
public boolean onTouchEvent(MotionEvent event){
    if(event.getAction() == MotionEvent.ACTION_DOWN){
        drawGlow = true;
    }else if(event.getAction() == MotionEvent.ACTION_UP)
        drawGlow = false;

    glowX = event.getX();
    glowY = event.getY();
    this.invalidate();
    return true;
}

}