You have to extend ImageView and override onTouchEvent() and onDraw() methods.
public class MyImageView extends ImageView {
private float lastX;
private float lastY;
...
public MyImageView(Context context) {
super(context);
}
public MyImageView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public MyImageView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
lastX = event.getX();
lastY = event.getY();
invalidate();
return super.onTouchEvent(event);
}
@Override
public void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawCircle(lastX, lastY, 60, myPaint);
}
}
and in your xml file instead of:
<ImageButton
android:id="@+id/imgView"
android:layout_width="match_parent"
android:layout_height="match_parent" />
use:
<my.package.MyImageView
android:id="@+id/imgView"
android:layout_width="match_parent"
android:layout_height="match_parent" />