Lock screen rotation while in gameplay.

osu.Android/GameplayScreenRotationLocker.cs

@@ -0,0 +1,31 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using Android.Content.PM;
+using osu.Framework.Allocation;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+using osu.Game;
+
+namespace osu.Android
+{
+    public class GameplayScreenRotationLocker : Component
+    {
+        private Bindable<bool> localUserPlaying;
+
+        [BackgroundDependencyLoader]
+        private void load(OsuGame game)
+        {
+            localUserPlaying = game.LocalUserPlaying.GetBoundCopy();
+            localUserPlaying.BindValueChanged(_ => updateLock());
+        }
+
+        private void updateLock()
+        {
+            OsuGameActivity.Activity.RunOnUiThread(() =>
+            {
+                OsuGameActivity.Activity.RequestedOrientation = localUserPlaying.Value ? ScreenOrientation.Locked : ScreenOrientation.FullUser;
+            });
+        }
+    }
+}

osu.Android/OsuGameActivity.cs

@@ -12,10 +12,14 @@ namespace osu.Android
     [Activity(Theme = "@android:style/Theme.NoTitleBar", MainLauncher = true, ScreenOrientation = ScreenOrientation.FullUser, SupportsPictureInPicture = false, ConfigurationChanges = ConfigChanges.Orientation | ConfigChanges.ScreenSize, HardwareAccelerated = false)]
     public class OsuGameActivity : AndroidGameActivity
     {
+        internal static Activity Activity;
+
         protected override Framework.Game CreateGame() => new OsuGameAndroid();
 
         protected override void OnCreate(Bundle savedInstanceState)
         {
+            Activity = this;
+
             // The default current directory on android is '/'.
             // On some devices '/' maps to the app data directory. On others it maps to the root of the internal storage.
             // In order to have a consistent current directory on all devices the full path of the app data directory is set as the current directory.

osu.Android/OsuGameAndroid.cs

@@ -55,6 +55,12 @@ public override Version AssemblyVersion
             }
         }
 
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+            LoadComponentAsync(new GameplayScreenRotationLocker(), Add);
+        }
+
         protected override UpdateManager CreateUpdateManager() => new SimpleUpdateManager();
     }
 }

osu.Android/osu.Android.csproj

@@ -21,6 +21,7 @@
     <AndroidLinkTool>r8</AndroidLinkTool>
   </PropertyGroup>
   <ItemGroup>
+    <Compile Include="GameplayScreenRotationLocker.cs" />
     <Compile Include="OsuGameActivity.cs" />
     <Compile Include="OsuGameAndroid.cs" />
   </ItemGroup>
@@ -53,4 +54,4 @@
     <AndroidResource Include="Resources\drawable\lazer.png" />
   </ItemGroup>
   <Import Project="$(MSBuildExtensionsPath)\Xamarin\Android\Xamarin.Android.CSharp.targets" />
-</Project>
+</Project>