android屏蔽返回键和home键

1. 屏蔽返回键的代码:
   public boolean onKeyDown(int keyCode,KeyEvent event){
   switch(keyCode){
   case KeyEvent.KEYCODE_HOME:return true;
   case KeyEvent.KEYCODE_BACK:return true;
   case KeyEvent.KEYCODE_CALL:return true;
   case KeyEvent.KEYCODE_SYM: return true;
   case KeyEvent.KEYCODE_VOLUME_DOWN: return true;
   case KeyEvent.KEYCODE_VOLUME_UP: return true;
   case KeyEvent.KEYCODE_STAR: return true;
   }
   return super.onKeyDown(keyCode, event);
   }

   屏蔽home键的代码:
   public void onAttachedToWindow() {
   this.getWindow().setType(WindowManager.LayoutParams.TYPE_KEYGUARD);
   super.onAttachedToWindow();
   }