Added MediaPlayer/Song stubs.

Added MessageBox for SDL.
Fixed platform Exit.

MonoGame.Framework/Media/MediaQueue.cs

@@ -111,14 +111,14 @@ internal void Clear()
 			for(; songs.Count > 0; )
 			{
 				song = songs[0];
-#if !DIRECTX && !NATIVE
+#if !DIRECTX
 				song.Stop();
 #endif
 				songs.Remove(song);
 			}
 		}
 
-#if !DIRECTX && !NATIVE
+#if !DIRECTX
         internal void SetVolume(float volume)
         {
             int count = songs.Count;
@@ -132,7 +132,7 @@ internal void Add(Song song)
             songs.Add(song);
         }
 
-#if !DIRECTX && !NATIVE
+#if !DIRECTX
         internal void Stop()
         {
             int count = songs.Count;

MonoGame.Framework/Media/Song.cs

@@ -48,7 +48,7 @@ public bool IsDisposed
             get { return disposed; }
         }
 
-#if ANDROID || OPENAL || WEB || IOS
+#if ANDROID || OPENAL || WEB || IOS || NATIVE
         internal delegate void FinishedPlayingHandler(object sender, EventArgs args);
 #if !DESKTOPGL
         event FinishedPlayingHandler DonePlaying;

MonoGame.Framework/MonoGame.Framework.Native.csproj

@@ -35,6 +35,7 @@
   <ItemGroup>
     <Compile Include="Platform\Input\InputKeyEventArgs.cs" />
     <Compile Include="Platform\Utilities\AssemblyHelper.cs" />
+    <Compile Include="Platform\Threading.cs" />
   </ItemGroup>
 
   <ItemGroup>

MonoGame.Framework/Platform/Native/GamePlatform.Native.cs

@@ -8,6 +8,7 @@
 using System.Collections.Generic;
 using System.Runtime.InteropServices;
 using MonoGame.Interop;
+using System.Threading;
 
 namespace Microsoft.Xna.Framework;
 
@@ -39,6 +40,7 @@ public unsafe NativeGamePlatform(Game game) : base(game)
         Window = _window;
 
         Mouse.WindowHandle = _window.Handle;
+        MessageBox._window = _window._handle;
     }
 
     internal static unsafe MGG_GraphicsSystem* GraphicsSystem
@@ -56,7 +58,7 @@ internal static unsafe MGG_GraphicsSystem* GraphicsSystem
 
     public override unsafe void Exit()
     {
-        MGP.Platform_Exit(Handle);
+        Interlocked.Increment(ref _isExiting);
     }
 
     public override unsafe void RunLoop()
@@ -69,6 +71,8 @@ public override unsafe void RunLoop()
 
             Game.Tick();
 
+            Threading.Run();
+
             if (_isExiting > 0 && ShouldExit())
                 break;
             else

MonoGame.Framework/Platform/Native/Media.Interop.cs

@@ -0,0 +1,54 @@
+// MonoGame - Copyright (C) The MonoGame Team
+// This file is subject to the terms and conditions defined in
+// file 'LICENSE.txt', which is part of this source code package.
+
+using System;
+using System.Runtime.InteropServices;
+
+namespace MonoGame.Interop;
+
+
+[MGHandle]
+internal readonly struct MGM_Song { }
+
+internal static unsafe partial class MGM
+{
+    const string MonoGameNativeDLL = "monogame.native";
+
+    #region Song
+
+    [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+    public delegate void NativeFinishedCallback(nint callbackData);
+
+    [LibraryImport(MonoGameNativeDLL, EntryPoint = "MGM_Song_Create", StringMarshalling = StringMarshalling.Utf8)]
+    public static partial MGM_Song* Song_Create(string mediaFilePath);
+
+    [LibraryImport(MonoGameNativeDLL, EntryPoint = "MGM_Song_GetDuration", StringMarshalling = StringMarshalling.Utf8)]
+    public static partial ulong Song_GetDuration(MGM_Song* song);
+
+    [LibraryImport(MonoGameNativeDLL, EntryPoint = "MGM_Song_GetPosition", StringMarshalling = StringMarshalling.Utf8)]
+    public static partial ulong Song_GetPosition(MGM_Song* song);
+
+    [LibraryImport(MonoGameNativeDLL, EntryPoint = "MGM_Song_GetVolume", StringMarshalling = StringMarshalling.Utf8)]
+    public static partial float Song_GetVolume(MGM_Song* song);
+
+    [LibraryImport(MonoGameNativeDLL, EntryPoint = "MGM_Song_SetVolume", StringMarshalling = StringMarshalling.Utf8)]
+    public static partial void Song_SetVolume(MGM_Song* song, float volume);
+
+    [LibraryImport(MonoGameNativeDLL, EntryPoint = "MGM_Song_Pause", StringMarshalling = StringMarshalling.Utf8)]
+    public static partial void Song_Pause(MGM_Song* song);
+
+    [LibraryImport(MonoGameNativeDLL, EntryPoint = "MGM_Song_Play", StringMarshalling = StringMarshalling.Utf8)]
+    public static partial void Song_Play(MGM_Song* song, ulong startPositionMs, [MarshalAs(UnmanagedType.FunctionPtr)] NativeFinishedCallback callback, nint callbackData);
+
+    [LibraryImport(MonoGameNativeDLL, EntryPoint = "MGM_Song_Resume", StringMarshalling = StringMarshalling.Utf8)]
+    public static partial void Song_Resume(MGM_Song* song);
+
+    [LibraryImport(MonoGameNativeDLL, EntryPoint = "MGM_Song_Stop", StringMarshalling = StringMarshalling.Utf8)]
+    public static partial void Song_Stop(MGM_Song* song);
+
+    [LibraryImport(MonoGameNativeDLL, EntryPoint = "MGM_Song_Destroy", StringMarshalling = StringMarshalling.Utf8)]
+    public static partial void Song_Destroy(MGM_Song* song);
+
+    #endregion
+}

MonoGame.Framework/Platform/Native/MediaPlayer.Native.cs

@@ -10,57 +10,70 @@ public static partial class MediaPlayer
 {
     private static void PlatformInitialize()
     {
-
     }
 
     private static bool PlatformGetIsMuted()
     {
-        return false;
+        return _isMuted;
     }
 
     private static void PlatformSetIsMuted(bool muted)
     {
+        _isMuted = muted;
+
+        if (_queue.Count == 0)
+            return;
 
+        var newVolume = _isMuted ? 0.0f : _volume;
+        _queue.SetVolume(newVolume);
     }
 
     private static bool PlatformGetIsRepeating()
     {
-        return false;
+        return _isRepeating;
     }
 
     private static void PlatformSetIsRepeating(bool repeating)
     {
-
+        _isRepeating = repeating;
     }
 
     private static bool PlatformGetIsShuffled()
     {
-        return false;
+        return _isShuffled;
     }
 
     private static void PlatformSetIsShuffled(bool shuffled)
     {
-
+        _isShuffled = shuffled;
     }
 
     private static TimeSpan PlatformGetPlayPosition()
     {
-        return TimeSpan.Zero;
+        if (_queue.ActiveSong == null)
+            return TimeSpan.Zero;
+
+        return _queue.ActiveSong.Position;
     }
 
     private static MediaState PlatformGetState()
     {
-        return MediaState.Stopped;
+        return _state;
     }
 
     private static float PlatformGetVolume()
     {
-        return 0.0f;
+        return _volume;
     }
 
     private static void PlatformSetVolume(float volume)
     {
+        _volume = volume;
 
+        if (_queue.ActiveSong == null)
+            return;
+
+        _queue.SetVolume(_isMuted ? 0.0f : _volume);
     }
 
     private static bool PlatformGetGameHasControl()
@@ -70,21 +83,33 @@ private static bool PlatformGetGameHasControl()
 
     private static void PlatformPause()
     {
+        if (_queue.ActiveSong == null)
+            return;
 
+        _queue.ActiveSong.Pause();
     }
 
     private static void PlatformPlaySong(Song song, TimeSpan? startPosition)
     {
+        if (_queue.ActiveSong == null)
+            return;
 
+        song.Volume = _isMuted ? 0.0f : _volume;
+        song.Play(startPosition, OnSongFinishedPlaying);
     }
 
     private static void PlatformResume()
     {
+        if (_queue.ActiveSong == null)
+            return;
 
+        _queue.ActiveSong.Resume();
     }
 
     private static void PlatformStop()
     {
-
+        // TOOD: What is this loop doing?
+        foreach (var song in Queue.Songs)
+            _queue.ActiveSong.Stop();
     }
 }

MonoGame.Framework/Platform/Native/MessageBox.Native.cs

@@ -2,16 +2,21 @@
 // This file is subject to the terms and conditions defined in
 // file 'LICENSE.txt', which is part of this source code package.
 
+using MonoGame.Interop;
 using System.Collections.Generic;
+using System.ComponentModel;
 using System.Threading.Tasks;
 
 namespace Microsoft.Xna.Framework.Input;
 
 public static partial class MessageBox
 {
-    private static Task<int?> PlatformShow(string title, string description, List<string> buttons)
+    internal static unsafe MGP_Window* _window;
+
+    private static unsafe Task<int?> PlatformShow(string title, string description, List<string> buttons)
     {
-        return Task.FromResult<int?>(0);
+        var result = MGP.Window_ShowMessageBox(_window, title, description, buttons.ToArray(), buttons.Count);
+        return Task.FromResult<int?>(result);
     }
 
     private static void PlatformCancel(int? result)

MonoGame.Framework/Platform/Native/Platform.Interop.cs

@@ -4,6 +4,7 @@
 
 using Microsoft.Xna.Framework;
 using Microsoft.Xna.Framework.Input;
+using System.Collections.Generic;
 using System.Runtime.InteropServices;
 
 namespace MonoGame.Interop;
@@ -224,9 +225,6 @@ internal static unsafe partial class MGP
     [LibraryImport(MonoGameNativeDLL, EntryPoint = "MGP_Platform_ExitFullScreen", StringMarshalling = StringMarshalling.Utf8)]
     public static partial void Platform_ExitFullScreen(MGP_Platform* platform);
 
-    [LibraryImport(MonoGameNativeDLL, EntryPoint = "MGP_Platform_Exit", StringMarshalling = StringMarshalling.Utf8)]
-    public static partial void Platform_Exit(MGP_Platform* platform);
-
     #endregion
 
     #region Window
@@ -270,6 +268,14 @@ internal static unsafe partial class MGP
     [LibraryImport(MonoGameNativeDLL, EntryPoint = "MGP_Window_SetPosition", StringMarshalling = StringMarshalling.Utf8)]
     public static partial void Window_SetPosition(MGP_Window* window, int x, int y);
 
+    [LibraryImport(MonoGameNativeDLL, EntryPoint = "MGP_Window_ShowMessageBox", StringMarshalling = StringMarshalling.Utf8)]
+    public static partial int Window_ShowMessageBox(
+         MGP_Window* window,
+         string title,
+         string description,
+         string[] buttons,
+         int count);
+
     #endregion
 
     #region Mouse