使应用程序全屏服务而非活动

Question

如何在服务中全屏显示应用程序？ （没有活动）

this.view = ((LayoutInflater)this.getSystemService("layout_inflater")).inflate(R.layout.lockscreen, (ViewGroup)null);
this.windowManager = (WindowManager)this.getSystemService("window");
final WindowManager.LayoutParams windowManagerLayoutParams = new WindowManager.LayoutParams();
windowManagerLayoutParams.type = 2002;
windowManagerLayoutParams.format = 1;
windowManagerLayoutParams.height = -1;
windowManagerLayoutParams.width = -1;
windowManager.addView(this.view, (WindowManager.LayoutParams)windowManagerLayoutParams);