Android 11 full screen display, hide navigation bar and status bar

 activity onCreate method,

setContentView(R.layout.activity_burn);

After setContentView, add the following code: 

        Window window = getWindow();
        window.getDecorView().setSystemUiVisibility(
                View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN  // 隐藏状态栏
                        | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION  // 隐藏导航栏
                        | View.SYSTEM_UI_FLAG_FULLSCREEN  // 全屏显示
                        | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION  // 隐藏导航栏
                        | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
        );