android 把控件放在屏幕任意位置

 private void showHalf() {
    
     WindowManager wm = PintuGameAct.this.getWindowManager();
    
     int width = wm.getDefaultDisplay().getWidth();
     int height = wm.getDefaultDisplay().getHeight();
     FrameLayout.LayoutParams flp = new FrameLayout.LayoutParams(
     FrameLayout.LayoutParams.FILL_PARENT,
     FrameLayout.LayoutParams.FILL_PARENT);
     flp.gravity = Gravity.CENTER;
     flp.topMargin = y;
     flp.leftMargin = x;
     flp.rightMargin = width - (x + view_width);
     flp.bottomMargin = height - (y + view_height);
     half.setLayoutParams(flp);
     }

x = a[0];
y = a[1];
int[] a = new int[2];
View.getLocationInWindow(a);