动态设置全屏，退出全屏

    private void setFullScreen(){
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
    }

    private void quitFullScreen(){
        final WindowManager.LayoutParams attrs = getWindow().getAttributes();
        attrs.flags &= (~WindowManager.LayoutParams.FLAG_FULLSCREEN);
        getWindow().setAttributes(attrs);
        getWindow().clearFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);
    }