private void DetachLayoutListener()
 {
     if (layoutListener != null)
     {
         ViewTreeObserver.RemoveGlobalOnLayoutListener(layoutListener);
         layoutListener = null;
     }
 }
 private void DetachLayoutListener()
 {
     if (layoutListener != null)
     {
         ViewTreeObserver.RemoveGlobalOnLayoutListener(layoutListener);
         layoutListener = null;
     }
 }
 private void AttachLayoutListener()
 {
     layoutListener = new LayoutListener(this);
     ViewTreeObserver.AddOnGlobalLayoutListener(layoutListener);
 }
 private void AttachLayoutListener()
 {
     layoutListener = new LayoutListener(this);
     ViewTreeObserver.AddOnGlobalLayoutListener(layoutListener);
 }