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I've got a problem with dark screen after opening minimized app (Android).

It happens in the following scenario:

I tap on a notification, the InfoPage opens. I press back button and it navigates to the main page. I minimize the app, and open it again. After opening again, the screen is black, with the name "InfoActivity" at the top, on a white bar.

Below I present the part of code for MainActivity and InfoPage.

In the MainActivity class, there is a code for opening InfoPage from notification. In the InfoPage class, there is a code for back button.

public class MainActivity : global::Xamarin.Forms.Platform.Android.FormsAppCompatActivity

 Bundle bundle;

 protected override void OnCreate(Bundle bundle)
 
 ...
 

 protected override void OnNewIntent(Intent intent)
 
 base.OnNewIntent(intent);
 Intent = intent;
 DisplayPage();
 

 public void DisplayPage()
 
 global::Xamarin.Forms.Forms.Init(this, bundle);
 Xamarin.Forms.Application app = new App();
 app.MainPage.Navigation.PushAsync(new InfoPage());
 LoadApplication(app);

 



public class InfoPage : BasePage

 public InfoPage()
 
 ...
 

 private void onClickBackButton(object sender, EventArgs e)
 
 Navigation.PopAsync();
 

 protected override bool OnBackButtonPressed()
 
 Navigation.PopAsync();
 return true;
 


[Activity(Label = "InfoActivity")]
public class InfoActivity : Activity

 protected override void OnCreate(Bundle savedInstanceState)
 
 Intent i = new Intent(this, typeof(MainActivity));
 i.AddFlags(ActivityFlags.ReorderToFront);
 this.StartActivity(i);

 base.OnCreate(savedInstanceState);
 

I am going to assuming that your Activity is not defined as a "singleTop"

LaunchMode = LaunchMode.SingleTop

And thus you are trying to reinitialize the Form's application when OnNewIntent is called.

1) Set your Activity to be a singleTop:

[Activity(Label = "FormsXXXX", Icon = "@mipmap/icon", Theme = "@style/MainTheme", LaunchMode = LaunchMode.SingleTop, MainLauncher = true, ConfigurationChanges = ConfigChanges.ScreenSize | ConfigChanges.Orientation)]
public class MainActivity : global::Xamarin.Forms.Platform.Android.FormsAppCompatActivity

 ...

2) Change your DisplayPage to only include the navigation PushAsync:

public void DisplayPage()

 Xamarin.Forms.Application.Current.MainPage.Navigation.PushAsync(new InfoPage());