Merge pull request #16924 from Susko3/android-allow-exiting

Allow exiting/minimizing the game on Android when on the initial screen

osu.Game/Screens/Menu/MainMenu.cs

@@ -2,15 +2,19 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
+using System.Diagnostics;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
+using osu.Framework.Input.Bindings;
+using osu.Framework.Input.Events;
 using osu.Framework.Platform;
 using osu.Framework.Screens;
 using osu.Game.Beatmaps;
 using osu.Game.Configuration;
 using osu.Game.Graphics;
 using osu.Game.Graphics.Containers;
+using osu.Game.Input.Bindings;
 using osu.Game.IO;
 using osu.Game.Online.API;
 using osu.Game.Overlays;
@@ -25,7 +29,7 @@ using osuTK.Graphics;
 
 namespace osu.Game.Screens.Menu
 {
-    public class MainMenu : OsuScreen, IHandlePresentBeatmap
+    public class MainMenu : OsuScreen, IHandlePresentBeatmap, IKeyBindingHandler<GlobalAction>
     {
         public const float FADE_IN_DURATION = 300;
 
@@ -297,5 +301,26 @@ namespace osu.Game.Screens.Menu
 
             Schedule(loadSoloSongSelect);
         }
+
+        public bool OnPressed(KeyBindingPressEvent<GlobalAction> e)
+        {
+            if (e.Repeat)
+                return false;
+
+            switch (e.Action)
+            {
+                case GlobalAction.Back:
+                    // In the case of a host being able to exit, the back action is handled by ExitConfirmOverlay.
+                    Debug.Assert(!host.CanExit);
+
+                    return host.SuspendToBackground();
+            }
+
+            return false;
+        }
+
+        public void OnReleased(KeyBindingReleaseEvent<GlobalAction> e)
+        {
+        }
     }
 }