Add code from target-android branch

Some changes to the added code were made so it would work with this structure.

SampleGame.Android/MainActivity.cs

@@ -0,0 +1,27 @@
+using Android.App;
+using Android.Widget;
+using Android.OS;
+
+namespace SampleGame.Android
+{
+    [Activity(Label = "SampleGame", MainLauncher = true, Icon = "@mipmap/icon")]
+    public class MainActivity : Activity
+    {
+        int count = 1;
+
+        protected override void OnCreate(Bundle savedInstanceState)
+        {
+            base.OnCreate(savedInstanceState);
+
+            // Set our view from the "main" layout resource
+            SetContentView(Resource.Layout.Main);
+
+            // Get our button from the layout resource,
+            // and attach an event to it
+            /*Button button = FindViewById<Button>(Resource.Id.myButton);
+
+            button.Click += delegate { button.Text = $"{count++} clicks!"; };*/
+        }
+    }
+}
+

SampleGame.Android/Properties/AndroidManifest.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="1" android:versionName="1.0" package="ppy.SampleGame">
+	<uses-sdk android:minSdkVersion="16" android:targetSdkVersion="28" />
+	<application android:allowBackup="true" android:icon="@mipmap/icon" android:label="@string/app_name"></application>
+</manifest>

SampleGame.Android/Resources/Resource.designer.cs

@@ -0,0 +1,117 @@
+#pragma warning disable 1591
+//------------------------------------------------------------------------------
+// <auto-generated>
+//     This code was generated by a tool.
+//     Runtime Version:4.0.30319.42000
+//
+//     Changes to this file may cause incorrect behavior and will be lost if
+//     the code is regenerated.
+// </auto-generated>
+//------------------------------------------------------------------------------
+
+[assembly: global::Android.Runtime.ResourceDesignerAttribute("SampleGame.Android.Resource", IsApplication=true)]
+
+namespace SampleGame.Android
+{
+	
+	
+	[System.CodeDom.Compiler.GeneratedCodeAttribute("Xamarin.Android.Build.Tasks", "1.0.0.0")]
+	public partial class Resource
+	{
+		
+		static Resource()
+		{
+			global::Android.Runtime.ResourceIdManager.UpdateIdValues();
+		}
+		
+		public static void UpdateIdValues()
+		{
+			global::osu.Framework.Android.Resource.String.library_name = global::SampleGame.Android.Resource.String.library_name;
+			global::osuTK.Android.Resource.String.library_name = global::SampleGame.Android.Resource.String.library_name;
+		}
+		
+		public partial class Attribute
+		{
+			
+			static Attribute()
+			{
+				global::Android.Runtime.ResourceIdManager.UpdateIdValues();
+			}
+			
+			private Attribute()
+			{
+			}
+		}
+		
+		public partial class Id
+		{
+			
+			// aapt resource value: 0x7f050000
+			public const int sampleGameView1 = 2131034112;
+			
+			static Id()
+			{
+				global::Android.Runtime.ResourceIdManager.UpdateIdValues();
+			}
+			
+			private Id()
+			{
+			}
+		}
+		
+		public partial class Layout
+		{
+			
+			// aapt resource value: 0x7f030000
+			public const int Main = 2130903040;
+			
+			static Layout()
+			{
+				global::Android.Runtime.ResourceIdManager.UpdateIdValues();
+			}
+			
+			private Layout()
+			{
+			}
+		}
+		
+		public partial class Mipmap
+		{
+			
+			// aapt resource value: 0x7f020000
+			public const int Icon = 2130837504;
+			
+			static Mipmap()
+			{
+				global::Android.Runtime.ResourceIdManager.UpdateIdValues();
+			}
+			
+			private Mipmap()
+			{
+			}
+		}
+		
+		public partial class String
+		{
+			
+			// aapt resource value: 0x7f040002
+			public const int app_name = 2130968578;
+			
+			// aapt resource value: 0x7f040001
+			public const int hello = 2130968577;
+			
+			// aapt resource value: 0x7f040000
+			public const int library_name = 2130968576;
+			
+			static String()
+			{
+				global::Android.Runtime.ResourceIdManager.UpdateIdValues();
+			}
+			
+			private String()
+			{
+			}
+		}
+	}
+}
+#pragma warning restore 1591

SampleGame.Android/Resources/layout/Main.axml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent">
+    <!--<Button android:id="@+id/myButton" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="@string/hello" />-->
+	<SampleGame.Android.SampleGameView 
+		android:id="@+id/sampleGameView1" android:layout_width="match_parent" android:layout_height="match_parent" />
+</LinearLayout>

SampleGame.Android/SampleGame.Android.csproj

@@ -0,0 +1,129 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <PropertyGroup>
+    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
+    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
+    <ProjectGuid>{5A378BB7-11D6-4008-980E-A67507CD9969}</ProjectGuid>
+    <ProjectTypeGuids>{EFBA0AD7-5A72-4C68-AF49-83D382785DCF};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>
+    <OutputType>Library</OutputType>
+    <RootNamespace>SampleGame.Android</RootNamespace>
+    <AssemblyName>SampleGame.Android</AssemblyName>
+    <TargetFrameworkVersion>v9.0</TargetFrameworkVersion>
+    <AndroidApplication>True</AndroidApplication>
+    <AndroidResgenFile>Resources\Resource.designer.cs</AndroidResgenFile>
+    <AndroidResgenClass>Resource</AndroidResgenClass>
+    <AndroidManifest>Properties\AndroidManifest.xml</AndroidManifest>
+    <MonoAndroidResourcePrefix>Resources</MonoAndroidResourcePrefix>
+    <MonoAndroidAssetsPrefix>Assets</MonoAndroidAssetsPrefix>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>full</DebugType>
+    <Optimize>false</Optimize>
+    <OutputPath>bin\Debug</OutputPath>
+    <DefineConstants>DEBUG;</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <AndroidLinkMode>None</AndroidLinkMode>
+    <JavaMaximumHeapSize>
+    </JavaMaximumHeapSize>
+    <LangVersion>Default</LangVersion>
+    <AndroidSupportedAbis>armeabi;armeabi-v7a;x86;arm64-v8a</AndroidSupportedAbis>
+    <AotAssemblies>false</AotAssemblies>
+    <EnableLLVM>false</EnableLLVM>
+    <BundleAssemblies>false</BundleAssemblies>
+    <MandroidI18n>CJK</MandroidI18n>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>pdbonly</DebugType>
+    <Optimize>true</Optimize>
+    <OutputPath>bin\Release</OutputPath>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <AndroidManagedSymbols>true</AndroidManagedSymbols>
+    <AndroidUseSharedRuntime>false</AndroidUseSharedRuntime>
+    <JavaMaximumHeapSize>
+    </JavaMaximumHeapSize>
+    <LangVersion>Default</LangVersion>
+  </PropertyGroup>
+  <ItemGroup>
+    <Reference Include="ManagedBass, Version=1.0.0.0, Culture=neutral, processorArchitecture=MSIL">
+      <HintPath>..\packages\ManagedBass.2.0.4\lib\netstandard1.4\ManagedBass.dll</HintPath>
+    </Reference>
+    <Reference Include="ManagedBass.Fx, Version=1.0.0.0, Culture=neutral, processorArchitecture=MSIL">
+      <HintPath>..\packages\ManagedBass.Fx.2.0.1\lib\netstandard1.4\ManagedBass.Fx.dll</HintPath>
+    </Reference>
+    <Reference Include="System" />
+    <Reference Include="System.IO.Compression" />
+    <Reference Include="System.Net.Http" />
+    <Reference Include="System.Xml" />
+    <Reference Include="System.Core" />
+    <Reference Include="Mono.Android" />
+    <Reference Include="osuTK.Android">
+      <HintPath>..\..\opentk\src\osuTK.Android\bin\Release\monoandroid50\50\osuTK.Android.dll</HintPath>
+    </Reference>
+    <Reference Include="osuTK">
+      <HintPath>..\..\opentk\src\osuTK\bin\Release\netstandard2.0\osuTK.dll</HintPath>
+    </Reference>
+  </ItemGroup>
+  <ItemGroup>
+    <Compile Include="MainActivity.cs" />
+    <Compile Include="Resources\Resource.designer.cs" />
+    <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="SampleGameView.cs" />
+  </ItemGroup>
+  <ItemGroup>
+    <AndroidNativeLibrary Include="lib\arm64-v8a\libbass.so">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </AndroidNativeLibrary>
+    <AndroidNativeLibrary Include="lib\arm64-v8a\libbass_fx.so">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </AndroidNativeLibrary>
+    <AndroidNativeLibrary Include="lib\armeabi-v7a\libbass.so">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </AndroidNativeLibrary>
+    <AndroidNativeLibrary Include="lib\armeabi-v7a\libbass_fx.so">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </AndroidNativeLibrary>
+    <None Include="app.config" />
+    <None Include="packages.config" />
+    <None Include="Resources\AboutResources.txt" />
+    <None Include="Properties\AndroidManifest.xml" />
+  </ItemGroup>
+  <ItemGroup>
+    <AndroidResource Include="Resources\layout\Main.axml" />
+    <AndroidResource Include="Resources\values\Strings.xml" />
+    <AndroidResource Include="Resources\mipmap-hdpi\Icon.png" />
+    <AndroidResource Include="Resources\mipmap-mdpi\Icon.png" />
+    <AndroidResource Include="Resources\mipmap-xhdpi\Icon.png" />
+    <AndroidResource Include="Resources\mipmap-xxhdpi\Icon.png" />
+    <AndroidResource Include="Resources\mipmap-xxxhdpi\Icon.png" />
+  </ItemGroup>
+  <ItemGroup>
+    <Folder Include="Resources\drawable\" />
+  </ItemGroup>
+  <ItemGroup>
+    <AndroidAsset Include="Assets\AboutAssets.txt" />
+  </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\osu.Framework.Android\osu.Framework.Android.csproj">
+      <Project>{87D8D3B5-7E16-4207-9972-8242AF1DEC3C}</Project>
+      <Name>osu.Framework.Android</Name>
+    </ProjectReference>
+    <ProjectReference Include="..\osu.Framework\osu.Framework.csproj">
+      <Project>{c76bf5b3-985e-4d39-95fe-97c9c879b83a}</Project>
+      <Name>osu.Framework</Name>
+    </ProjectReference>
+    <ProjectReference Include="..\SampleGame\SampleGame.csproj">
+      <Project>{E3882853-43D1-4603-AD33-D9D59C8A8692}</Project>
+      <Name>SampleGame</Name>
+    </ProjectReference>
+  </ItemGroup>
+  <ItemGroup>
+    <Content Include="bass.dll">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
+  </ItemGroup>
+  <Import Project="$(MSBuildExtensionsPath)\Xamarin\Android\Xamarin.Android.CSharp.targets" />
+</Project>

SampleGame.Android/SampleGameView.cs

@@ -0,0 +1,25 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+using Android.App;
+using Android.Content;
+using Android.OS;
+using Android.Runtime;
+using Android.Util;
+using Android.Views;
+using Android.Widget;
+using osu.Framework;
+
+namespace SampleGame.Android
+{
+    class SampleGameView : osu.Framework.Android.AndroidGameView
+    {
+        public SampleGameView(Context context, IAttributeSet attrs) : base(context, attrs)
+        {
+            CreateGame();
+        }
+        public override Game CreateGame() => new SampleGameGame();
+    }
+}

SampleGame.Android/app.config

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<configuration>
+  <runtime>
+    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
+      <dependentAssembly>
+        <assemblyIdentity name="System.Buffers" publicKeyToken="cc7b13ffcd2ddd51" culture="neutral" />
+        <bindingRedirect oldVersion="0.0.0.0-4.0.3.0" newVersion="4.0.3.0" />
+      </dependentAssembly>
+    </assemblyBinding>
+  </runtime>
+</configuration>

SampleGame.Android/packages.config

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<packages>
+  <package id="ManagedBass" version="2.0.4" targetFramework="monoandroid90" />
+  <package id="ManagedBass.Fx" version="2.0.1" targetFramework="monoandroid90" />
+</packages>

osu-framework.sln

@@ -9,7 +9,7 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "SampleGame", "SampleGame\Sa
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "osu.Framework.Tests", "osu.Framework.Tests\osu.Framework.Tests.csproj", "{79803407-6F50-484F-93F5-641911EABD8A}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SampleGame.Desktop", "SampleGame.Desktop\SampleGame.Desktop.csproj", "{2AD6EA6F-CD5A-4348-86F1-5E228B11617D}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "SampleGame.Desktop", "SampleGame.Desktop\SampleGame.Desktop.csproj", "{2AD6EA6F-CD5A-4348-86F1-5E228B11617D}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
@@ -34,4 +34,10 @@ Global
 		{2AD6EA6F-CD5A-4348-86F1-5E228B11617D}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{2AD6EA6F-CD5A-4348-86F1-5E228B11617D}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {27D12E10-E38E-4ECE-8DD1-77E8C387B2DD}
+	EndGlobalSection
 EndGlobal

osu.Framework.Android/AndroidGameHost.cs

@@ -0,0 +1,41 @@
+// Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu-framework/master/LICENCE
+
+using System;
+using System.Collections.Generic;
+using osu.Framework.Input;
+using osu.Framework.Input.Handlers;
+using osu.Framework.Platform;
+using osuTK;
+
+namespace osu.Framework.Android
+{
+    public class AndroidGameHost : GameHost
+    {
+        private readonly AndroidGameView gameView;
+
+        public AndroidGameHost(AndroidGameView gameView)
+        {
+            this.gameView = gameView;
+            Window = new AndroidGameWindow(gameView);
+            Window.WindowStateChanged += (sender, e) =>
+            {
+                if (Window.WindowState != WindowState.Minimized)
+                    OnActivated();
+                else
+                    OnDeactivated();
+            };
+        }
+
+        public override ITextInputSource GetTextInput() => throw new NotImplementedException();// new AndroidTextInput(gameView);
+
+        protected override IEnumerable<InputHandler> CreateAvailableInputHandlers() =>
+            new InputHandler[] { };//new AndroidTouchHandler(gameView), new AndroidKeyboardHandler(gameView) };
+
+        protected override Storage GetStorage(string baseName) => new AndroidStorage(baseName, this);
+
+        public override void OpenFileExternally(string filename) => throw new NotImplementedException();
+
+        public override void OpenUrlExternally(string url) => throw new NotImplementedException();
+    }
+}

osu.Framework.Android/AndroidGameWindow.cs

@@ -0,0 +1,46 @@
+// Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu-framework/master/LICENCE
+
+using System;
+using System.Linq;
+using System.Reflection;
+using osu.Framework.Configuration;
+using osu.Framework.Platform;
+using osuTK.Graphics;
+
+namespace osu.Framework.Android
+{
+    public class AndroidGameWindow : GameWindow
+    {
+        private readonly AndroidGameView view;
+
+        protected new osuTK.GameWindow Implementation => (osuTK.GameWindow)base.Implementation;
+
+        public AndroidGameWindow(AndroidGameView view) : base(new AndroidPlatformWindow(view))
+        {
+            this.view = view;
+
+            Load += OnLoad;
+        }
+
+        public override void SetupWindow(FrameworkConfigManager config)
+        {
+            //throw new NotImplementedException();
+        }
+
+        public override IGraphicsContext Context => view.GraphicsContext;
+
+        public override bool Focused => true;
+
+        public override osuTK.WindowState WindowState { get => osuTK.WindowState.Normal; set { } }
+
+        protected void OnLoad(object sender, EventArgs e)
+        {
+            var implementationField = typeof(osuTK.NativeWindow).GetRuntimeFields().Single(x => x.Name == "implementation");
+
+            var windowImpl = implementationField.GetValue(Implementation);
+
+            //isSdl = windowImpl.GetType().Name == "Sdl2NativeWindow";
+        }
+    }
+}

osu.Framework.Android/AndroidPlatformWindow.cs

@@ -0,0 +1,144 @@
+using System;
+using System.ComponentModel;
+using System.Drawing;
+using System.Threading;
+using osuTK;
+using osuTK.Input;
+using osuTK.Platform;
+
+namespace osu.Framework.Android
+{
+    public class AndroidPlatformWindow : IGameWindow
+    {
+        private readonly AndroidGameView gameView;
+
+        public AndroidPlatformWindow(AndroidGameView gameView)
+        {
+            this.gameView = gameView;
+
+            gameView.Load += (o, e) => Load?.Invoke(o, e);
+            gameView.Unload += (o, e) => Unload?.Invoke(o, e);
+            gameView.UpdateFrame += (o, e) => UpdateFrame?.Invoke(o, e);
+            gameView.RenderFrame += (o, e) => RenderFrame?.Invoke(o, e);
+            gameView.Resize += (o, e) => Resize?.Invoke(o, e);
+            gameView.Closed += (o, e) => Closed?.Invoke(o, e);
+            gameView.Disposed += (o, e) => Disposed?.Invoke(o, e);
+            gameView.TitleChanged += (o, e) => TitleChanged?.Invoke(o, e);
+            gameView.VisibleChanged += (o, e) => VisibleChanged?.Invoke(o, e);
+            gameView.WindowStateChanged += (o, e) => WindowStateChanged?.Invoke(o, e);
+        }
+        // We cannot have titles.
+        public string Title { get => gameView.Title; set { } }
+
+        // Always set this to true.
+        public bool Focused => true;
+
+        public bool Visible { get => gameView.Visible; set { } }
+
+        public bool Exists => true;
+
+        public IWindowInfo WindowInfo => gameView.WindowInfo;
+
+        public WindowState WindowState { get => WindowState.Fullscreen; set { } }
+        public WindowBorder WindowBorder { get => WindowBorder.Hidden; set { } }
+        public Rectangle Bounds { get => new Rectangle(0, 0, Width, Height); set { } }
+        public Point Location { get => Point.Empty; set { } }
+        public Size Size { get => new Size((int)(gameView.Size.Width * gameView.ScaleX), (int)(gameView.Height * gameView.ScaleY)); set { } }
+        public int X { get => 0; set { } }
+        public int Y { get => 0; set { } }
+        public int Width { get => Size.Width; set { } }
+        public int Height { get => Size.Height; set { } }
+        public Rectangle ClientRectangle { get => new Rectangle(0, 0, Width, Height); set { } }
+        public Size ClientSize { get => Size; set { } }
+        public MouseCursor Cursor { get => MouseCursor.Default; set { } }
+        public bool CursorVisible { get => false; set { } }
+        public bool CursorGrabbed { get => true; set { } }
+
+        public Icon Icon { get => throw new NotImplementedException(); set => throw new NotImplementedException(); }
+
+        public event EventHandler<EventArgs> Load;
+        public event EventHandler<EventArgs> Unload;
+        public event EventHandler<FrameEventArgs> UpdateFrame;
+        public event EventHandler<FrameEventArgs> RenderFrame;
+        public event EventHandler<EventArgs> Move;
+        public event EventHandler<EventArgs> Resize;
+        public event EventHandler<CancelEventArgs> Closing;
+        public event EventHandler<EventArgs> Closed;
+        public event EventHandler<EventArgs> Disposed;
+        public event EventHandler<EventArgs> IconChanged;
+        public event EventHandler<EventArgs> TitleChanged;
+        public event EventHandler<EventArgs> VisibleChanged;
+        public event EventHandler<EventArgs> FocusedChanged;
+        public event EventHandler<EventArgs> WindowBorderChanged;
+        public event EventHandler<EventArgs> WindowStateChanged;
+        public event EventHandler<KeyboardKeyEventArgs> KeyDown;
+        public event EventHandler<KeyPressEventArgs> KeyPress;
+        public event EventHandler<KeyboardKeyEventArgs> KeyUp;
+        public event EventHandler<EventArgs> MouseLeave;
+        public event EventHandler<EventArgs> MouseEnter;
+        public event EventHandler<MouseButtonEventArgs> MouseDown;
+        public event EventHandler<MouseButtonEventArgs> MouseUp;
+        public event EventHandler<MouseMoveEventArgs> MouseMove;
+        public event EventHandler<MouseWheelEventArgs> MouseWheel;
+        public event EventHandler<FileDropEventArgs> FileDrop;
+
+        public void Close()
+        {
+            gameView.Close();
+        }
+
+        public void Dispose()
+        {
+            gameView.Dispose();
+        }
+
+        public void MakeCurrent()
+        {
+            gameView.MakeCurrent();
+        }
+
+        public Point PointToClient(Point point)
+        {
+            return point;
+        }
+
+        public Point PointToScreen(Point point)
+        {
+            return point;
+        }
+
+        public void ProcessEvents()
+        {
+            gameView.ProcessEvents();
+        }
+
+        public void Run()
+        {
+            new Thread(() =>
+            {
+                while (true)
+                {
+                    gameView.Handler.Post(() =>
+                    {
+                        RenderFrame?.Invoke(this, new FrameEventArgs() { });
+                        SwapBuffers();
+                    });
+                    UpdateFrame?.Invoke(this, new FrameEventArgs() { });
+
+                    Thread.Sleep(100);
+                }
+            });
+            gameView.Run();
+        }
+
+        public void Run(double updateRate)
+        {
+            gameView.Run(updateRate);
+        }
+
+        public void SwapBuffers()
+        {
+            gameView.SwapBuffers();
+        }
+    }
+}

osu.Framework.Android/AndroidStorage.cs

@@ -0,0 +1,75 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+using Android.App;
+using Android.Content;
+using Android.OS;
+using Android.Runtime;
+using Android.Views;
+using Android.Widget;
+using osu.Framework.Platform;
+
+namespace osu.Framework.Android
+{
+    class AndroidStorage : DesktopStorage
+    {
+        public AndroidStorage(string baseName, GameHost host)
+            : base(baseName, host)
+        {
+            BasePath = LocateBasePath();
+        }
+
+        //Dopilnuj, aby zamieniać ścieżki względne na bezwzględne
+
+        protected override string LocateBasePath()
+        {
+            return (string)Application.Context.GetExternalFilesDir("");
+        }
+
+        /*public override string[] GetFiles(string path) => (string[])Directory.EnumerateFiles(GetUsablePathFor(path));
+        public override string[] GetDirectories(string path) => Directory.GetDirectories(GetUsablePathFor(path));
+        public override void Delete(string path)
+        {
+            FileSafety.FileDelete(GetUsablePathFor(path));
+        }
+        public override bool Exists(string path)
+        {
+            return File.Exists(GetUsablePathFor(path));
+        }
+        public override void DeleteDirectory(string path)
+        {
+            path = GetUsablePathFor(path);
+            // handles the case where the directory doesn't exist, which will throw a DirectoryNotFoundException.
+            if (Directory.Exists(path))
+                Directory.Delete(path, true);
+        }
+        public override bool ExistsDirectory(string path) => Directory.Exists(GetUsablePathFor(path));
+        public override Stream GetStream(string path, FileAccess access = FileAccess.Read, FileMode mode = FileMode.OpenOrCreate)
+        {
+            path = GetUsablePathFor(path, access != FileAccess.Read);
+            if (string.IsNullOrEmpty(path))
+                throw new ArgumentNullException(nameof(path));
+            switch (access)
+            {
+                case FileAccess.Read:
+                    if (!File.Exists(path)) return null;
+                    return File.Open(path, FileMode.Open, access, FileShare.Read);
+                default:
+                    return File.Open(path, mode, access);
+            }
+        }
+        public override string GetDatabaseConnectionString(string name)
+        {
+            return string.Concat("Data Source=", GetUsablePathFor($@"{name}.db", true));
+        }
+        public override void DeleteDatabase(string name) => Delete($@"{name}.db");*/
+
+        public override void OpenInNativeExplorer()
+        {
+            //Not needed now.
+            throw new NotImplementedException();
+        }
+    }
+}

osu.Framework.Android/osu.Framework.Android.csproj

@@ -0,0 +1,135 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <Import Project="..\packages\NUnit.3.10.1\build\NUnit.props" Condition="Exists('..\packages\NUnit.3.10.1\build\NUnit.props')" />
+  <PropertyGroup>
+    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
+    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
+    <ProjectGuid>{87D8D3B5-7E16-4207-9972-8242AF1DEC3C}</ProjectGuid>
+    <ProjectTypeGuids>{EFBA0AD7-5A72-4C68-AF49-83D382785DCF};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>
+    <OutputType>Library</OutputType>
+    <RootNamespace>osu.Framework.Android</RootNamespace>
+    <AssemblyName>osu.Framework.Android</AssemblyName>
+    <TargetFrameworkVersion>v9.0</TargetFrameworkVersion>
+    <AndroidResgenFile>Resources\Resource.designer.cs</AndroidResgenFile>
+    <AndroidResgenClass>Resource</AndroidResgenClass>
+    <MonoAndroidResourcePrefix>Resources</MonoAndroidResourcePrefix>
+    <MonoAndroidAssetsPrefix>Assets</MonoAndroidAssetsPrefix>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>full</DebugType>
+    <Optimize>false</Optimize>
+    <OutputPath>bin\Debug</OutputPath>
+    <DefineConstants>DEBUG;</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <AndroidLinkMode>None</AndroidLinkMode>
+    <JavaMaximumHeapSize>
+    </JavaMaximumHeapSize>
+    <LangVersion>Default</LangVersion>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>pdbonly</DebugType>
+    <Optimize>true</Optimize>
+    <OutputPath>bin\Release</OutputPath>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <AndroidManagedSymbols>true</AndroidManagedSymbols>
+    <AndroidUseSharedRuntime>false</AndroidUseSharedRuntime>
+    <JavaMaximumHeapSize>
+    </JavaMaximumHeapSize>
+    <LangVersion>Default</LangVersion>
+  </PropertyGroup>
+  <ItemGroup>
+    <Reference Include="System" />
+    <Reference Include="System.Xml" />
+    <Reference Include="System.Core" />
+    <Reference Include="Mono.Android" />
+    <Reference Include="osuTK.Android">
+      <HintPath>..\..\opentk\src\osuTK.Android\bin\Release\monoandroid50\50\osuTK.Android.dll</HintPath>
+    </Reference>
+    <Reference Include="osuTK">
+      <HintPath>..\..\opentk\src\osuTK\bin\Release\netstandard2.0\osuTK.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Collections.Immutable">
+      <HintPath>..\packages\System.Collections.Immutable.1.5.0\lib\netstandard2.0\System.Collections.Immutable.dll</HintPath>
+    </Reference>
+    <Reference Include="JetBrains.Annotations">
+      <HintPath>..\packages\JetBrains.Annotations.2018.2.1\lib\netstandard2.0\JetBrains.Annotations.dll</HintPath>
+    </Reference>
+    <Reference Include="System.IO.Compression" />
+    <Reference Include="System.Reflection.Metadata">
+      <HintPath>..\packages\System.Reflection.Metadata.1.6.0\lib\netstandard2.0\System.Reflection.Metadata.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Threading.Tasks.Extensions">
+      <HintPath>..\packages\System.Threading.Tasks.Extensions.4.3.0\lib\portable-net45+win8+wp8+wpa81\System.Threading.Tasks.Extensions.dll</HintPath>
+    </Reference>
+    <Reference Include="System.ValueTuple">
+      <HintPath>..\packages\System.ValueTuple.4.3.0\lib\netstandard1.0\System.ValueTuple.dll</HintPath>
+    </Reference>
+    <Reference Include="Microsoft.CodeAnalysis">
+      <HintPath>..\packages\Microsoft.CodeAnalysis.Common.2.9.0\lib\netstandard1.3\Microsoft.CodeAnalysis.dll</HintPath>
+    </Reference>
+    <Reference Include="Microsoft.CodeAnalysis.CSharp">
+      <HintPath>..\packages\Microsoft.CodeAnalysis.CSharp.2.9.0\lib\netstandard1.3\Microsoft.CodeAnalysis.CSharp.dll</HintPath>
+    </Reference>
+    <Reference Include="nunit.framework">
+      <HintPath>..\packages\NUnit.3.10.1\lib\netstandard2.0\nunit.framework.dll</HintPath>
+    </Reference>
+    <Reference Include="Microsoft.Diagnostics.Runtime">
+      <HintPath>..\packages\ppy.Microsoft.Diagnostics.Runtime.0.9.180305.1\lib\netstandard2.0\Microsoft.Diagnostics.Runtime.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Buffers">
+      <HintPath>..\packages\System.Buffers.4.5.0\lib\netstandard2.0\System.Buffers.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Runtime.CompilerServices.Unsafe">
+      <HintPath>..\packages\System.Runtime.CompilerServices.Unsafe.4.5.1\lib\netstandard2.0\System.Runtime.CompilerServices.Unsafe.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Memory">
+      <HintPath>..\packages\System.Memory.4.5.1\lib\netstandard2.0\System.Memory.dll</HintPath>
+    </Reference>
+    <Reference Include="SixLabors.Core">
+      <HintPath>..\packages\SixLabors.Core.1.0.0-beta0006\lib\netstandard1.1\SixLabors.Core.dll</HintPath>
+    </Reference>
+    <Reference Include="SixLabors.ImageSharp">
+      <HintPath>..\packages\SixLabors.ImageSharp.1.0.0-beta0005\lib\netstandard2.0\SixLabors.ImageSharp.dll</HintPath>
+    </Reference>
+    <Reference Include="Newtonsoft.Json">
+      <HintPath>..\packages\Newtonsoft.Json.11.0.2\lib\netstandard2.0\Newtonsoft.Json.dll</HintPath>
+    </Reference>
+    <Reference Include="Cyotek.Drawing.BitmapFont">
+      <HintPath>..\packages\Cyotek.Drawing.BitmapFont.1.3.4\lib\netstandard1.3\Cyotek.Drawing.BitmapFont.dll</HintPath>
+    </Reference>
+    <Reference Include="ManagedBass">
+      <HintPath>..\packages\ManagedBass.2.0.4\lib\netstandard1.4\ManagedBass.dll</HintPath>
+    </Reference>
+    <Reference Include="ManagedBass.Fx">
+      <HintPath>..\packages\ManagedBass.Fx.2.0.1\lib\netstandard1.4\ManagedBass.Fx.dll</HintPath>
+    </Reference>
+  </ItemGroup>
+  <ItemGroup>
+    <Compile Include="AndroidPlatformWindow.cs" />
+    <Compile Include="AndroidStorage.cs" />
+    <Compile Include="Resources\Resource.designer.cs" />
+    <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="AndroidGameWindow.cs" />
+    <Compile Include="AndroidGameView.cs" />
+    <Compile Include="AndroidGameHost.cs" />
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="Resources\AboutResources.txt" />
+    <None Include="packages.config" />
+  </ItemGroup>
+  <ItemGroup>
+    <AndroidResource Include="Resources\values\Strings.xml" />
+  </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\osu.Framework\osu.Framework.csproj">
+      <Project>{C76BF5B3-985E-4D39-95FE-97C9C879B83A}</Project>
+      <Name>osu.Framework</Name>
+    </ProjectReference>
+  </ItemGroup>
+  <Import Project="$(MSBuildExtensionsPath)\Xamarin\Android\Xamarin.Android.CSharp.targets" />
+  <Import Project="..\packages\NETStandard.Library.2.0.0\build\netstandard2.0\NETStandard.Library.targets" Condition="Exists('..\packages\NETStandard.Library.2.0.0\build\netstandard2.0\NETStandard.Library.targets')" />
+</Project>