android开发：屏幕点亮与屏幕取消点亮

//设置窗体始终点亮

getWindow().setFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON,
      WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);

//取消窗体始终点亮

getWindow().setFlags(0, WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);