Android 向windowmanager添加按钮

我想做一个锁屏应用程序，我使用覆盖窗口。但若我想在我的窗口管理器中添加一些按钮，我该怎么做呢？在用户按下按钮之后，我应该使用哪个命令

我的代码：

DisplayMetrics metrics = getResources().getDisplayMetrics();
        int densityDpi = (int)(metrics.density * 160f);
        LayoutInflater li = (LayoutInflater) getSystemService(LAYOUT_INFLATER_SERVICE);
        WindowManager windowManager = (WindowManager) getApplicationContext().getSystemService(Context.WINDOW_SERVICE);
        mTopView = (RelativeLayout) li.inflate(R.layout.red_layout, null, false);
int LayoutParamFlags = WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN
                | WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION
                | WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS;

        WindowManager.LayoutParams params = new WindowManager.LayoutParams(
                WindowManager.LayoutParams.MATCH_PARENT,
                densityDpi * 4,
                WindowManager.LayoutParams.TYPE_SYSTEM_OVERLAY,
                LayoutParamFlags,
                PixelFormat.TRANSLUCENT);
        windowManager.addView(mTopView,params);

多谢各位