Convert everything to use IScreen

osu.Desktop/OsuGameDesktop.cs

@@ -16,7 +16,6 @@ using osu.Desktop.Updater;
 using osu.Framework;
 using osu.Framework.Platform.Windows;
 using osu.Framework.Screens;
-using osu.Game.Screens;
 using osu.Game.Screens.Menu;
 
 namespace osu.Desktop
@@ -63,9 +62,10 @@ namespace osu.Desktop
             }
         }
 
-        protected override void ScreenChanged(OsuScreen current, Screen newScreen)
+        protected override void ScreenChanged(IScreen lastScreen, IScreen newScreen)
         {
-            base.ScreenChanged(current, newScreen);
+            base.ScreenChanged(lastScreen, newScreen);
+
             switch (newScreen)
             {
                 case Intro _:

osu.Game.Tests/Visual/TestCaseLoaderAnimation.cs

@@ -4,6 +4,7 @@
 using NUnit.Framework;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Shapes;
+using osu.Framework.Screens;
 using osu.Game.Screens;
 using osu.Game.Screens.Menu;
 using osuTK.Graphics;
@@ -57,7 +58,7 @@ namespace osu.Game.Tests.Visual
             public OsuLogo Logo;
             private TestScreen screen;
 
-            public bool ScreenLoaded => screen.IsCurrentScreen;
+            public bool ScreenLoaded => screen.IsCurrentScreen();
 
             public TestLoader(double delay)
             {
@@ -96,7 +97,7 @@ namespace osu.Game.Tests.Visual
             {
                 public TestScreen()
                 {
-                    Child = new Box
+                    InternalChild = new Box
                     {
                         RelativeSizeAxes = Axes.Both,
                         Colour = Color4.DarkSlateGray,
@@ -107,7 +108,7 @@ namespace osu.Game.Tests.Visual
                 protected override void LogoArriving(OsuLogo logo, bool resuming)
                 {
                     base.LogoArriving(logo, resuming);
-                    Child.FadeInFromZero(200);
+                    InternalChild.FadeInFromZero(200);
                 }
             }
         }

osu.Game.Tests/Visual/TestCaseMultiHeader.cs

@@ -3,6 +3,7 @@
 
 using NUnit.Framework;
 using osu.Framework.Graphics;
+using osu.Framework.Screens;
 using osu.Game.Screens;
 using osu.Game.Screens.Multi;
 
@@ -15,15 +16,15 @@ namespace osu.Game.Tests.Visual
         {
             int index = 0;
 
-            OsuScreen currentScreen = new TestMultiplayerSubScreen(index);
+            ScreenStack screenStack = new ScreenStack(new TestMultiplayerSubScreen(index)) { RelativeSizeAxes = Axes.Both };
 
             Children = new Drawable[]
             {
-                currentScreen,
-                new Header(currentScreen)
+                screenStack,
+                new Header(screenStack)
             };
 
-            AddStep("push multi screen", () => currentScreen.Push(currentScreen = new TestMultiplayerSubScreen(++index)));
+            AddStep("push multi screen", () => screenStack.CurrentScreen.Push(new TestMultiplayerSubScreen(++index)));
         }
 
         private class TestMultiplayerSubScreen : OsuScreen, IMultiplayerSubScreen

osu.Game.Tests/Visual/TestCaseMultiScreen.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Collections.Generic;
 using NUnit.Framework;
+using osu.Framework.Screens;
 using osu.Game.Screens.Multi;
 using osu.Game.Screens.Multi.Lounge;
 using osu.Game.Screens.Multi.Lounge.Components;

osu.Game.Tests/Visual/TestCasePlayerLoader.cs

@@ -3,6 +3,7 @@
 
 using System.Threading;
 using osu.Framework.Allocation;
+using osu.Framework.Screens;
 using osu.Game.Beatmaps;
 using osu.Game.Screens.Play;
 
@@ -26,7 +27,7 @@ namespace osu.Game.Tests.Visual
 
             AddStep("mouse in centre", () => InputManager.MoveMouseTo(loader.ScreenSpaceDrawQuad.Centre));
 
-            AddUntilStep(() => !loader.IsCurrentScreen, "wait for no longer current");
+            AddUntilStep(() => !loader.IsCurrentScreen(), "wait for no longer current");
 
             AddStep("load slow dummy beatmap", () =>
             {
@@ -42,7 +43,7 @@ namespace osu.Game.Tests.Visual
                 Scheduler.AddDelayed(() => slow.Ready = true, 5000);
             });
 
-            AddUntilStep(() => !loader.IsCurrentScreen, "wait for no longer current");
+            AddUntilStep(() => !loader.IsCurrentScreen(), "wait for no longer current");
         }
 
         protected class SlowLoadPlayer : Player

osu.Game.Tests/Visual/TestCaseScreenBreadcrumbControl.cs

@@ -19,16 +19,18 @@ namespace osu.Game.Tests.Visual
     public class TestCaseScreenBreadcrumbControl : OsuTestCase
     {
         private readonly ScreenBreadcrumbControl breadcrumbs;
-        private Screen currentScreen, changedScreen;
+        private readonly ScreenStack screenStack;
 
         public TestCaseScreenBreadcrumbControl()
         {
-            TestScreen startScreen;
             OsuSpriteText titleText;
 
+            IScreen startScreen = new TestScreenOne();
+            screenStack = new ScreenStack(startScreen) { RelativeSizeAxes = Axes.Both };
+
             Children = new Drawable[]
             {
-                currentScreen = startScreen = new TestScreenOne(),
+                screenStack,
                 new FillFlowContainer
                 {
                     RelativeSizeAxes = Axes.X,
@@ -37,7 +39,7 @@ namespace osu.Game.Tests.Visual
                     Spacing = new Vector2(10),
                     Children = new Drawable[]
                     {
-                        breadcrumbs = new ScreenBreadcrumbControl(startScreen)
+                        breadcrumbs = new ScreenBreadcrumbControl(screenStack)
                         {
                             RelativeSizeAxes = Axes.X,
                         },
@@ -46,12 +48,7 @@ namespace osu.Game.Tests.Visual
                 },
             };
 
-            breadcrumbs.Current.ValueChanged += s =>
-            {
-                titleText.Text = $"Changed to {s.ToString()}";
-                changedScreen = s;
-            };
-
+            breadcrumbs.Current.ValueChanged += s => titleText.Text = $"Changed to {s.ToString()}";
             breadcrumbs.Current.TriggerChange();
 
             waitForCurrent();
@@ -60,18 +57,14 @@ namespace osu.Game.Tests.Visual
             pushNext();
             waitForCurrent();
 
-            AddStep(@"make start current", () =>
-            {
-                startScreen.MakeCurrent();
-                currentScreen = startScreen;
-            });
+            AddStep(@"make start current", () => startScreen.MakeCurrent());
 
             waitForCurrent();
             pushNext();
             waitForCurrent();
             AddAssert(@"only 2 items", () => breadcrumbs.Items.Count() == 2);
-            AddStep(@"exit current", () => changedScreen.Exit());
-            AddAssert(@"current screen is first", () => startScreen == changedScreen);
+            AddStep(@"exit current", () => screenStack.CurrentScreen.Exit());
+            AddAssert(@"current screen is first", () => startScreen == screenStack.CurrentScreen);
         }
 
         [BackgroundDependencyLoader]
@@ -80,8 +73,8 @@ namespace osu.Game.Tests.Visual
             breadcrumbs.StripColour = colours.Blue;
         }
 
-        private void pushNext() => AddStep(@"push next screen", () => currentScreen = ((TestScreen)currentScreen).PushNext());
-        private void waitForCurrent() => AddUntilStep(() => currentScreen.IsCurrentScreen, "current screen");
+        private void pushNext() => AddStep(@"push next screen", () => ((TestScreen)screenStack.CurrentScreen).PushNext());
+        private void waitForCurrent() => AddUntilStep(() => screenStack.CurrentScreen.IsCurrentScreen(), "current screen");
 
         private abstract class TestScreen : OsuScreen
         {
@@ -91,14 +84,14 @@ namespace osu.Game.Tests.Visual
             public TestScreen PushNext()
             {
                 TestScreen screen = CreateNextScreen();
-                Push(screen);
+               this.Push(screen);
 
                 return screen;
             }
 
             protected TestScreen()
             {
-                Child = new FillFlowContainer
+                InternalChild = new FillFlowContainer
                 {
                     Anchor = Anchor.Centre,
                     Origin = Anchor.Centre,

osu.Game/Graphics/Cursor/MenuCursorContainer.cs

@@ -50,6 +50,7 @@ namespace osu.Game.Graphics.Cursor
             if (!CanShowCursor)
             {
                 currentTarget?.Cursor?.Hide();
+                currentTarget = null;
                 return;
             }
 

osu.Game/Graphics/UserInterface/ScreenBreadcrumbControl.cs

@@ -10,45 +10,26 @@ namespace osu.Game.Graphics.UserInterface
     /// <summary>
     /// A <see cref="BreadcrumbControl"/> which follows the active screen (and allows navigation) in a <see cref="Screen"/> stack.
     /// </summary>
-    public class ScreenBreadcrumbControl : BreadcrumbControl<Screen>
+    public class ScreenBreadcrumbControl : BreadcrumbControl<IScreen>
     {
-        private Screen last;
-
-        public ScreenBreadcrumbControl(Screen initialScreen)
+        public ScreenBreadcrumbControl(ScreenStack stack)
         {
-            Current.ValueChanged += newScreen =>
-            {
-                if (last != newScreen && !newScreen.IsCurrentScreen)
-                    newScreen.MakeCurrent();
-            };
+            stack.ScreenPushed += onPushed;
+            stack.ScreenExited += onExited;
 
-            onPushed(initialScreen);
+            Current.ValueChanged += newScreen => newScreen.MakeCurrent();
         }
 
-        private void screenChanged(Screen newScreen)
+        private void onPushed(IScreen lastScreen, IScreen newScreen)
         {
-            if (newScreen == null) return;
-
-            if (last != null)
-            {
-                last.Exited -= screenChanged;
-                last.ModePushed -= onPushed;
-            }
-
-            last = newScreen;
-
-            newScreen.Exited += screenChanged;
-            newScreen.ModePushed += onPushed;
-
             Current.Value = newScreen;
+            AddItem(newScreen);
         }
 
-        private void onPushed(Screen screen)
+        private void onExited(IScreen lastScreen, IScreen newScreen)
         {
-            Items.ToList().SkipWhile(i => i != Current.Value).Skip(1).ForEach(RemoveItem);
-            AddItem(screen);
-
-            screenChanged(screen);
+            Current.Value = newScreen;
+            Items.ToList().SkipWhile(s => s != Current.Value).Skip(1).ForEach(RemoveItem);
         }
     }
 }

osu.Game/OsuGame.cs

@@ -79,27 +79,21 @@ namespace osu.Game
 
         public virtual Storage GetStorageForStableInstall() => null;
 
-        private Intro intro
-        {
-            get
-            {
-                Screen screen = screenStack;
-                while (screen != null && !(screen is Intro))
-                    screen = screen.ChildScreen;
-                return screen as Intro;
-            }
-        }
-
         public float ToolbarOffset => Toolbar.Position.Y + Toolbar.DrawHeight;
 
         private IdleTracker idleTracker;
 
         public readonly Bindable<OverlayActivation> OverlayActivationMode = new Bindable<OverlayActivation>();
 
-        private OsuScreen screenStack;
-
+        private ParallaxContainer backgroundParallax;
+        private ScreenStack backgroundStack;
+        private ScreenStack screenStack;
         private VolumeOverlay volume;
         private OnScreenDisplay onscreenDisplay;
+        private OsuLogo osuLogo;
+
+        private MainMenu menuScreen;
+        private Intro introScreen;
 
         private Bindable<int> configRuleset;
         private readonly Bindable<RulesetInfo> ruleset = new Bindable<RulesetInfo>();
@@ -173,6 +167,8 @@ namespace osu.Game
             dependencies.CacheAs(ruleset);
             dependencies.CacheAs<IBindable<RulesetInfo>>(ruleset);
 
+            dependencies.Cache(osuLogo = new OsuLogo());
+
             // bind config int to database RulesetInfo
             configRuleset = LocalConfig.GetBindable<int>(OsuSetting.Ruleset);
             ruleset.Value = RulesetStore.GetRuleset(configRuleset.Value) ?? RulesetStore.AvailableRulesets.First();
@@ -211,6 +207,12 @@ namespace osu.Game
         /// <param name="beatmap">The beatmap to select.</param>
         public void PresentBeatmap(BeatmapSetInfo beatmap)
         {
+            if (menuScreen == null)
+            {
+                Schedule(() => PresentBeatmap(beatmap));
+                return;
+            }
+
             CloseAllOverlays(false);
 
             void setBeatmap()
@@ -235,16 +237,15 @@ namespace osu.Game
                 }
             }
 
-            switch (currentScreen)
+            switch (screenStack.CurrentScreen)
             {
                 case SongSelect _:
                     break;
                 default:
                     // navigate to song select if we are not already there.
-                    var menu = (MainMenu)intro.ChildScreen;
 
-                    menu.MakeCurrent();
-                    menu.LoadToSolo();
+                    menuScreen.MakeCurrent();
+                    menuScreen.LoadToSolo();
                     break;
             }
 
@@ -270,9 +271,7 @@ namespace osu.Game
 
             scoreLoad?.Cancel();
 
-            var menu = intro.ChildScreen;
-
-            if (menu == null)
+            if (menuScreen == null)
             {
                 scoreLoad = Schedule(() => LoadScore(score, false));
                 return;
@@ -293,7 +292,7 @@ namespace osu.Game
                 return;
             }
 
-            if (!currentScreen.AllowExternalScreenChange)
+            if ((screenStack.CurrentScreen as IOsuScreen)?.AllowExternalScreenChange != true)
             {
                 notifications.Post(new SimpleNotification
                 {
@@ -312,9 +311,9 @@ namespace osu.Game
 
             void loadScore()
             {
-                if (!menu.IsCurrentScreen)
+                if (!menuScreen.IsCurrentScreen())
                 {
-                    menu.MakeCurrent();
+                    menuScreen.MakeCurrent();
                     this.Delay(500).Schedule(loadScore, out scoreLoad);
                     return;
                 }
@@ -324,7 +323,7 @@ namespace osu.Game
                 Beatmap.Value = BeatmapManager.GetWorkingBeatmap(databasedBeatmap);
                 Beatmap.Value.Mods.Value = databasedScoreInfo.Mods;
 
-                currentScreen.Push(new PlayerLoader(() => new ReplayPlayer(databasedScore)));
+                menuScreen.Push(new PlayerLoader(() => new ReplayPlayer(databasedScore)));
             }
         }
 
@@ -338,11 +337,6 @@ namespace osu.Game
         {
             base.LoadComplete();
 
-            // The next time this is updated is in UpdateAfterChildren, which occurs too late and results
-            // in the cursor being shown for a few frames during the intro.
-            // This prevents the cursor from showing until we have a screen with CursorVisible = true
-            MenuCursorContainer.CanShowCursor = currentScreen?.CursorVisible ?? false;
-
             // todo: all archive managers should be able to be looped here.
             SkinManager.PostNotification = n => notifications?.Post(n);
             SkinManager.GetStableStorage = GetStorageForStableInstall;
@@ -352,6 +346,8 @@ namespace osu.Game
 
             BeatmapManager.PresentBeatmap = PresentBeatmap;
 
+            Container logoContainer;
+
             AddRange(new Drawable[]
             {
                 new VolumeControlReceptor
@@ -360,10 +356,18 @@ namespace osu.Game
                     ActionRequested = action => volume.Adjust(action),
                     ScrollActionRequested = (action, amount, isPrecise) => volume.Adjust(action, amount, isPrecise),
                 },
+                backgroundParallax = new ParallaxContainer
+                {
+                    RelativeSizeAxes = Axes.Both,
+                    Scale = new Vector2(1.06f),
+                    Child = backgroundStack = new ScreenStack { RelativeSizeAxes = Axes.Both }
+                },
                 screenContainer = new ScalingContainer(ScalingMode.ExcludeOverlays)
                 {
                     RelativeSizeAxes = Axes.Both,
+                    Child = screenStack = new ScreenStack { RelativeSizeAxes = Axes.Both }
                 },
+                logoContainer = new Container { RelativeSizeAxes = Axes.Both },
                 overlayContent = new Container
                 {
                     RelativeSizeAxes = Axes.Both,
@@ -372,12 +376,15 @@ namespace osu.Game
                 idleTracker = new IdleTracker(6000)
             });
 
-            loadComponentSingleFile(screenStack = new Loader(), d =>
+            screenStack.ScreenPushed += screenPushed;
+            screenStack.ScreenExited += screenExited;
+
+            loadComponentSingleFile(osuLogo, logoContainer.Add);
+
+            loadComponentSingleFile(new Loader
             {
-                screenStack.ModePushed += screenAdded;
-                screenStack.Exited += screenRemoved;
-                screenContainer.Add(screenStack);
-            });
+                RelativeSizeAxes = Axes.Both
+            }, screenStack.Push);
 
             loadComponentSingleFile(Toolbar = new Toolbar
             {
@@ -385,7 +392,7 @@ namespace osu.Game
                 OnHome = delegate
                 {
                     CloseAllOverlays(false);
-                    intro?.ChildScreen?.MakeCurrent();
+                    menuScreen?.MakeCurrent();
                 },
             }, floatingOverlayContent.Add);
 
@@ -601,7 +608,7 @@ namespace osu.Game
 
         public bool OnPressed(GlobalAction action)
         {
-            if (intro == null) return false;
+            if (introScreen == null) return false;
 
             switch (action)
             {
@@ -658,25 +665,9 @@ namespace osu.Game
 
         private Container floatingOverlayContent;
 
-        private OsuScreen currentScreen;
         private FrameworkConfigManager frameworkConfig;
         private ScalingContainer screenContainer;
 
-        protected override bool OnExiting()
-        {
-            if (screenStack.ChildScreen == null) return false;
-
-            if (intro == null) return true;
-
-            if (!intro.DidLoadMenu || intro.ChildScreen != null)
-            {
-                Scheduler.Add(intro.MakeCurrent);
-                return true;
-            }
-
-            return base.OnExiting();
-        }
-
         /// <summary>
         /// Use to programatically exit the game as if the user was triggering via alt-f4.
         /// Will keep persisting until an exit occurs (exit may be blocked multiple times).
@@ -695,7 +686,7 @@ namespace osu.Game
 
             // we only want to apply these restrictions when we are inside a screen stack.
             // the use case for not applying is in visual/unit tests.
-            bool applyBeatmapRulesetRestrictions = !currentScreen?.AllowBeatmapRulesetChange ?? false;
+            bool applyBeatmapRulesetRestrictions = !(screenStack.CurrentScreen as IOsuScreen)?.AllowBeatmapRulesetChange ?? false;
 
             ruleset.Disabled = applyBeatmapRulesetRestrictions;
             Beatmap.Disabled = applyBeatmapRulesetRestrictions;
@@ -703,7 +694,7 @@ namespace osu.Game
             screenContainer.Padding = new MarginPadding { Top = ToolbarOffset };
             overlayContent.Padding = new MarginPadding { Top = ToolbarOffset };
 
-            MenuCursorContainer.CanShowCursor = currentScreen?.CursorVisible ?? false;
+            MenuCursorContainer.CanShowCursor = (screenStack.CurrentScreen as IOsuScreen)?.CursorVisible ?? false;
         }
 
         /// <summary>
@@ -732,24 +723,38 @@ namespace osu.Game
             this.ruleset.Disabled = rulesetDisabled;
         }
 
-        protected virtual void ScreenChanged(OsuScreen current, Screen newScreen)
+        protected virtual void ScreenChanged(IScreen lastScreen, IScreen newScreen)
         {
-            currentScreen = (OsuScreen)newScreen;
+            if (newScreen is IOsuScreen newOsuScreen)
+                backgroundParallax.ParallaxAmount = ParallaxContainer.DEFAULT_PARALLAX_AMOUNT * newOsuScreen.BackgroundParallaxAmount;
+
+            switch (newScreen)
+            {
+                case Intro intro:
+                    introScreen = intro;
+                    break;
+                case MainMenu menu:
+                    menuScreen = menu;
+                    break;
+            }
         }
 
-        private void screenAdded(Screen newScreen)
+        private void screenPushed(IScreen lastScreen, IScreen newScreen)
         {
-            ScreenChanged(currentScreen, newScreen);
+            if (newScreen is IOsuScreen newOsuScreen && newOsuScreen.Background != null)
+                backgroundStack.Push(newOsuScreen.Background);
+
+            ScreenChanged(lastScreen, newScreen);
             Logger.Log($"Screen changed → {newScreen}");
-
-            newScreen.ModePushed += screenAdded;
-            newScreen.Exited += screenRemoved;
         }
 
-        private void screenRemoved(Screen newScreen)
+        private void screenExited(IScreen lastScreen, IScreen newScreen)
         {
-            ScreenChanged(currentScreen, newScreen);
-            Logger.Log($"Screen changed ← {currentScreen}");
+            if (newScreen is IOsuScreen newOsuScreen)
+                newOsuScreen.Background?.MakeCurrent();
+
+            ScreenChanged(lastScreen, newScreen);
+            Logger.Log($"Screen changed ← {newScreen}");
 
             if (newScreen == null)
                 Exit();

osu.Game/Overlays/AccountCreation/AccountCreationScreen.cs

@@ -8,22 +8,22 @@ namespace osu.Game.Overlays.AccountCreation
 {
     public abstract class AccountCreationScreen : Screen
     {
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             base.OnEntering(last);
-            Content.FadeOut().Delay(200).FadeIn(200);
+            this.FadeOut().Delay(200).FadeIn(200);
         }
 
-        protected override void OnResuming(Screen last)
+        public override void OnResuming(IScreen last)
         {
             base.OnResuming(last);
-            Content.FadeIn(200);
+            this.FadeIn(200);
         }
 
-        protected override void OnSuspending(Screen next)
+        public override void OnSuspending(IScreen next)
         {
             base.OnSuspending(next);
-            Content.FadeOut(200);
+            this.FadeOut(200);
         }
     }
 }

osu.Game/Overlays/AccountCreation/ScreenEntry.cs

@@ -44,7 +44,7 @@ namespace osu.Game.Overlays.AccountCreation
         {
             this.api = api;
 
-            Children = new Drawable[]
+            InternalChildren = new Drawable[]
             {
                 new FillFlowContainer
                 {
@@ -143,7 +143,7 @@ namespace osu.Game.Overlays.AccountCreation
                 focusNextTextbox();
         }
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             base.OnEntering(last);
             processingOverlay.Hide();

osu.Game/Overlays/AccountCreation/ScreenWarning.cs

@@ -26,12 +26,12 @@ namespace osu.Game.Overlays.AccountCreation
 
         private const string help_centre_url = "/help/wiki/Help_Centre#login";
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             if (string.IsNullOrEmpty(api.ProvidedUsername))
             {
-                Content.FadeOut();
-                Push(new ScreenEntry());
+                this.FadeOut();
+                this.Push(new ScreenEntry());
                 return;
             }
 
@@ -46,7 +46,7 @@ namespace osu.Game.Overlays.AccountCreation
             if (string.IsNullOrEmpty(api.ProvidedUsername))
                 return;
 
-            Children = new Drawable[]
+            InternalChildren = new Drawable[]
             {
                 new Sprite
                 {
@@ -104,7 +104,7 @@ namespace osu.Game.Overlays.AccountCreation
                         new DangerousSettingsButton
                         {
                             Text = "I understand. This account isn't for me.",
-                            Action = () => Push(new ScreenEntry())
+                            Action = () => this.Push(new ScreenEntry())
                         },
                         furtherAssistance = new LinkFlowContainer(cp => { cp.TextSize = 12; })
                         {

osu.Game/Overlays/AccountCreation/ScreenWelcome.cs

@@ -4,6 +4,7 @@
 using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
+using osu.Framework.Screens;
 using osu.Game.Graphics.Sprites;
 using osu.Game.Overlays.Settings;
 using osu.Game.Screens.Menu;
@@ -16,7 +17,7 @@ namespace osu.Game.Overlays.AccountCreation
         [BackgroundDependencyLoader]
         private void load()
         {
-            Child = new FillFlowContainer
+            InternalChild = new FillFlowContainer
             {
                 RelativeSizeAxes = Axes.Both,
                 Direction = FillDirection.Vertical,
@@ -56,7 +57,7 @@ namespace osu.Game.Overlays.AccountCreation
                     {
                         Text = "Let's create an account!",
                         Margin = new MarginPadding { Vertical = 120 },
-                        Action = () => Push(new ScreenWarning())
+                        Action = () => this.Push(new ScreenWarning())
                     }
                 }
             };

osu.Game/Overlays/AccountCreationOverlay.cs

@@ -6,6 +6,7 @@ using osu.Framework.Extensions.Color4Extensions;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Shapes;
+using osu.Framework.Screens;
 using osu.Game.Graphics;
 using osu.Game.Graphics.Containers;
 using osu.Game.Online.API;
@@ -82,7 +83,7 @@ namespace osu.Game.Overlays
             base.PopIn();
             this.FadeIn(transition_time, Easing.OutQuint);
 
-            if (welcomeScreen.ChildScreen != null)
+            if (welcomeScreen.GetChildScreen() != null)
                 welcomeScreen.MakeCurrent();
         }
 

osu.Game/Screens/BackgroundScreen.cs

@@ -2,7 +2,6 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using System;
-using System.Threading;
 using osu.Framework.Screens;
 using osu.Framework.Graphics;
 using osu.Framework.Input.Events;
@@ -12,6 +11,12 @@ namespace osu.Game.Screens
 {
     public abstract class BackgroundScreen : Screen, IEquatable<BackgroundScreen>
     {
+        protected BackgroundScreen()
+        {
+            Anchor = Anchor.Centre;
+            Origin = Anchor.Centre;
+        }
+
         public virtual bool Equals(BackgroundScreen other)
         {
             return other?.GetType() == GetType();
@@ -26,64 +31,40 @@ namespace osu.Game.Screens
             return false;
         }
 
-        public override void Push(Screen screen)
-        {
-            // When trying to push a non-loaded screen, load it asynchronously and re-invoke Push
-            // once it's done.
-            if (screen.LoadState == LoadState.NotLoaded)
-            {
-                LoadComponentAsync(screen, d => Push((BackgroundScreen)d));
-                return;
-            }
-
-            // Make sure the in-progress loading is complete before pushing the screen.
-            while (screen.LoadState < LoadState.Ready)
-                Thread.Sleep(1);
-
-            try
-            {
-                base.Push(screen);
-            }
-            catch (ScreenAlreadyExitedException)
-            {
-                // screen may have exited before the push was successful.
-            }
-        }
-
         protected override void Update()
         {
             base.Update();
-            Content.Scale = new Vector2(1 + x_movement_amount / DrawSize.X * 2);
+            Scale = new Vector2(1 + x_movement_amount / DrawSize.X * 2);
         }
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
-            Content.FadeOut();
-            Content.MoveToX(x_movement_amount);
+            this.FadeOut();
+            this.MoveToX(x_movement_amount);
 
-            Content.FadeIn(transition_length, Easing.InOutQuart);
-            Content.MoveToX(0, transition_length, Easing.InOutQuart);
+            this.FadeIn(transition_length, Easing.InOutQuart);
+            this.MoveToX(0, transition_length, Easing.InOutQuart);
 
             base.OnEntering(last);
         }
 
-        protected override void OnSuspending(Screen next)
+        public override void OnSuspending(IScreen next)
         {
-            Content.MoveToX(-x_movement_amount, transition_length, Easing.InOutQuart);
+            this.MoveToX(-x_movement_amount, transition_length, Easing.InOutQuart);
             base.OnSuspending(next);
         }
 
-        protected override bool OnExiting(Screen next)
+        public override bool OnExiting(IScreen next)
         {
-            Content.FadeOut(transition_length, Easing.OutExpo);
-            Content.MoveToX(x_movement_amount, transition_length, Easing.OutExpo);
+            this.FadeOut(transition_length, Easing.OutExpo);
+            this.MoveToX(x_movement_amount, transition_length, Easing.OutExpo);
 
             return base.OnExiting(next);
         }
 
-        protected override void OnResuming(Screen last)
+        public override void OnResuming(IScreen last)
         {
-            Content.MoveToX(0, transition_length, Easing.OutExpo);
+            this.MoveToX(0, transition_length, Easing.OutExpo);
             base.OnResuming(last);
         }
     }

osu.Game/Screens/Backgrounds/BackgroundScreenBeatmap.cs

@@ -37,7 +37,7 @@ namespace osu.Game.Screens.Backgrounds
                         }
 
                         b.Depth = newDepth;
-                        Add(Background = b);
+                        AddInternal(Background = b);
                         Background.BlurSigma = BlurTarget;
                     }));
                 });

osu.Game/Screens/Backgrounds/BackgroundScreenBlack.cs

@@ -12,14 +12,14 @@ namespace osu.Game.Screens.Backgrounds
     {
         public BackgroundScreenBlack()
         {
-            Child = new Box
+            InternalChild = new Box
             {
                 Colour = Color4.Black,
                 RelativeSizeAxes = Axes.Both,
             };
         }
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             Show();
         }

osu.Game/Screens/Backgrounds/BackgroundScreenCustom.cs

@@ -12,7 +12,7 @@ namespace osu.Game.Screens.Backgrounds
         public BackgroundScreenCustom(string textureName)
         {
             this.textureName = textureName;
-            Add(new Background(textureName));
+            AddInternal(new Background(textureName));
         }
 
         public override bool Equals(BackgroundScreen other)

osu.Game/Screens/Backgrounds/BackgroundScreenDefault.cs

@@ -42,7 +42,7 @@ namespace osu.Game.Screens.Backgrounds
             Background?.FadeOut(800, Easing.InOutSine);
             Background?.Expire();
 
-            Add(Background = newBackground);
+            AddInternal(Background = newBackground);
             currentDisplay++;
         }
 

osu.Game/Screens/Edit/Editor.cs

@@ -65,7 +65,7 @@ namespace osu.Game.Screens.Edit
             SummaryTimeline timeline;
             PlaybackControl playback;
 
-            Children = new[]
+            InternalChildren = new[]
             {
                 new Container
                 {
@@ -96,7 +96,7 @@ namespace osu.Game.Screens.Edit
                                 {
                                     new EditorMenuItem("Export", MenuItemType.Standard, exportBeatmap),
                                     new EditorMenuItemSpacer(),
-                                    new EditorMenuItem("Exit", MenuItemType.Standard, Exit)
+                                    new EditorMenuItem("Exit", MenuItemType.Standard, this.Exit)
                                 }
                             }
                         }
@@ -194,20 +194,20 @@ namespace osu.Game.Screens.Edit
             return true;
         }
 
-        protected override void OnResuming(Screen last)
+        public override void OnResuming(IScreen last)
         {
             Beatmap.Value.Track?.Stop();
             base.OnResuming(last);
         }
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             base.OnEntering(last);
             Background.FadeColour(Color4.DarkGray, 500);
             Beatmap.Value.Track?.Stop();
         }
 
-        protected override bool OnExiting(Screen next)
+        public override bool OnExiting(IScreen next)
         {
             Background.FadeColour(Color4.White, 500);
             if (Beatmap.Value.Track != null)

osu.Game/Screens/IOsuScreen.cs

@@ -0,0 +1,27 @@
+// Copyright (c) 2007-2019 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using osu.Framework.Screens;
+
+namespace osu.Game.Screens
+{
+    public interface IOsuScreen : IScreen
+    {
+        /// <summary>
+        /// Whether the beatmap or ruleset should be allowed to be changed by the user or game.
+        /// Used to mark exclusive areas where this is strongly prohibited, like gameplay.
+        /// </summary>
+        bool AllowBeatmapRulesetChange { get; }
+
+        bool AllowExternalScreenChange { get; }
+
+        /// <summary>
+        /// Whether this <see cref="OsuScreen"/> allows the cursor to be displayed.
+        /// </summary>
+        bool CursorVisible { get; }
+
+        BackgroundScreen Background { get; }
+
+        float BackgroundParallaxAmount { get; }
+    }
+}

osu.Game/Screens/Loader.cs

@@ -55,11 +55,11 @@ namespace osu.Game.Screens
 
         protected virtual ShaderPrecompiler CreateShaderPrecompiler() => new ShaderPrecompiler();
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             base.OnEntering(last);
 
-            LoadComponentAsync(precompiler = CreateShaderPrecompiler(), Add);
+            LoadComponentAsync(precompiler = CreateShaderPrecompiler(), AddInternal);
             LoadComponentAsync(loadableScreen = CreateLoadableScreen());
 
             checkIfLoaded();
@@ -73,7 +73,7 @@ namespace osu.Game.Screens
                 return;
             }
 
-            Push(loadableScreen);
+            this.Push(loadableScreen);
         }
 
         [BackgroundDependencyLoader]

osu.Game/Screens/Menu/Disclaimer.cs

@@ -41,7 +41,7 @@ namespace osu.Game.Screens.Menu
         [BackgroundDependencyLoader]
         private void load(OsuColour colours)
         {
-            Children = new Drawable[]
+            InternalChildren = new Drawable[]
             {
                 icon = new SpriteIcon
                 {
@@ -116,7 +116,7 @@ namespace osu.Game.Screens.Menu
             LoadComponentAsync(intro = new Intro());
         }
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             base.OnEntering(last);
 
@@ -130,12 +130,12 @@ namespace osu.Game.Screens.Menu
 
             supporterDrawables.ForEach(d => d.FadeOut().Delay(2000).FadeIn(500));
 
-            Content
+            this
                 .FadeInFromZero(500)
                 .Then(5500)
                 .FadeOut(250)
                 .ScaleTo(0.9f, 250, Easing.InQuint)
-                .Finally(d => Push(intro));
+                .Finally(d => this.Push(intro));
 
             heart.FlashColour(Color4.White, 750, Easing.OutQuint).Loop();
         }

osu.Game/Screens/Menu/Intro.cs

@@ -111,7 +111,7 @@ namespace osu.Game.Screens.Menu
                     Scheduler.AddDelayed(delegate
                     {
                         DidLoadMenu = true;
-                        Push(mainMenu);
+                        this.Push(mainMenu);
                     }, delay_step_one);
                 }, delay_step_two);
             }
@@ -145,22 +145,22 @@ namespace osu.Game.Screens.Menu
             }
         }
 
-        protected override void OnSuspending(Screen next)
+        public override void OnSuspending(IScreen next)
         {
-            Content.FadeOut(300);
+            this.FadeOut(300);
             base.OnSuspending(next);
         }
 
-        protected override bool OnExiting(Screen next)
+        public override bool OnExiting(IScreen next)
         {
             //cancel exiting if we haven't loaded the menu yet.
             return !DidLoadMenu;
         }
 
-        protected override void OnResuming(Screen last)
+        public override void OnResuming(IScreen last)
         {
             if (!(last is MainMenu))
-                Content.FadeIn(300);
+                this.FadeIn(300);
 
             double fadeOutTime = EXIT_DELAY;
             //we also handle the exit transition.
@@ -169,7 +169,7 @@ namespace osu.Game.Screens.Menu
             else
                 fadeOutTime = 500;
 
-            Scheduler.AddDelayed(Exit, fadeOutTime);
+            Scheduler.AddDelayed(this.Exit, fadeOutTime);
 
             //don't want to fade out completely else we will stop running updates and shit will hit the fan.
             Game.FadeTo(0.01f, fadeOutTime);

osu.Game/Screens/Menu/MainMenu.cs

@@ -31,22 +31,19 @@ namespace osu.Game.Screens.Menu
 
         public override bool AllowExternalScreenChange => true;
 
-        private readonly BackgroundScreenDefault background;
         private Screen songSelect;
 
         private readonly MenuSideFlashes sideFlashes;
 
-        protected override BackgroundScreen CreateBackground() => background;
+        protected override BackgroundScreen CreateBackground() => new BackgroundScreenDefault();
 
         public MainMenu()
         {
-            background = new BackgroundScreenDefault();
-
-            Children = new Drawable[]
+            InternalChildren = new Drawable[]
             {
                 new ExitConfirmOverlay
                 {
-                    Action = Exit,
+                    Action = this.Exit,
                 },
                 new ParallaxContainer
                 {
@@ -55,12 +52,12 @@ namespace osu.Game.Screens.Menu
                     {
                         buttons = new ButtonSystem
                         {
-                            OnChart = delegate { Push(new ChartListing()); },
-                            OnDirect = delegate { Push(new OnlineListing()); },
-                            OnEdit = delegate { Push(new Editor()); },
+                            OnChart = delegate { this.Push(new ChartListing()); },
+                            OnDirect = delegate {this.Push(new OnlineListing()); },
+                            OnEdit = delegate {this.Push(new Editor()); },
                             OnSolo = onSolo,
-                            OnMulti = delegate { Push(new Multiplayer()); },
-                            OnExit = Exit,
+                            OnMulti = delegate {this.Push(new Multiplayer()); },
+                            OnExit = this.Exit,
                         }
                     }
                 },
@@ -73,10 +70,10 @@ namespace osu.Game.Screens.Menu
                 {
                     case ButtonSystemState.Initial:
                     case ButtonSystemState.Exit:
-                        background.FadeColour(Color4.White, 500, Easing.OutSine);
+                        Background.FadeColour(Color4.White, 500, Easing.OutSine);
                         break;
                     default:
-                        background.FadeColour(OsuColour.Gray(0.8f), 500, Easing.OutSine);
+                        Background.FadeColour(OsuColour.Gray(0.8f), 500, Easing.OutSine);
                         break;
                 }
             };
@@ -85,8 +82,6 @@ namespace osu.Game.Screens.Menu
         [BackgroundDependencyLoader(true)]
         private void load(OsuGame game = null)
         {
-            LoadComponentAsync(background);
-
             if (game != null)
             {
                 buttons.OnSettings = game.ToggleSettings;
@@ -104,7 +99,7 @@ namespace osu.Game.Screens.Menu
 
         public void LoadToSolo() => Schedule(onSolo);
 
-        private void onSolo() => Push(consumeSongSelect());
+        private void onSolo() =>this.Push(consumeSongSelect());
 
         private Screen consumeSongSelect()
         {
@@ -113,7 +108,7 @@ namespace osu.Game.Screens.Menu
             return s;
         }
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             base.OnEntering(last);
             buttons.FadeInFromZero(500);
@@ -148,8 +143,8 @@ namespace osu.Game.Screens.Menu
 
                 const float length = 300;
 
-                Content.FadeIn(length, Easing.OutQuint);
-                Content.MoveTo(new Vector2(0, 0), length, Easing.OutQuint);
+                this.FadeIn(length, Easing.OutQuint);
+                this.MoveTo(new Vector2(0, 0), length, Easing.OutQuint);
 
                 sideFlashes.Delay(length).FadeIn(64, Easing.InQuint);
             }
@@ -164,13 +159,13 @@ namespace osu.Game.Screens.Menu
 
         private void beatmap_ValueChanged(WorkingBeatmap newValue)
         {
-            if (!IsCurrentScreen)
+            if (!this.IsCurrentScreen())
                 return;
 
-            background.Next();
+            ((BackgroundScreenDefault)Background).Next();
         }
 
-        protected override void OnSuspending(Screen next)
+        public override void OnSuspending(IScreen next)
         {
             base.OnSuspending(next);
 
@@ -178,26 +173,26 @@ namespace osu.Game.Screens.Menu
 
             buttons.State = ButtonSystemState.EnteringMode;
 
-            Content.FadeOut(length, Easing.InSine);
-            Content.MoveTo(new Vector2(-800, 0), length, Easing.InSine);
+            this.FadeOut(length, Easing.InSine);
+            this.MoveTo(new Vector2(-800, 0), length, Easing.InSine);
 
             sideFlashes.FadeOut(64, Easing.OutQuint);
         }
 
-        protected override void OnResuming(Screen last)
+        public override void OnResuming(IScreen last)
         {
             base.OnResuming(last);
 
-            background.Next();
+            ((BackgroundScreenDefault)Background).Next();
 
             //we may have consumed our preloaded instance, so let's make another.
             preloadSongSelect();
         }
 
-        protected override bool OnExiting(Screen next)
+        public override bool OnExiting(IScreen next)
         {
             buttons.State = ButtonSystemState.Exit;
-            Content.FadeOut(3000);
+            this.FadeOut(3000);
             return base.OnExiting(next);
         }
 
@@ -205,7 +200,7 @@ namespace osu.Game.Screens.Menu
         {
             if (!e.Repeat && e.ControlPressed && e.ShiftPressed && e.Key == Key.D)
             {
-                Push(new Drawings());
+               this.Push(new Drawings());
                 return true;
             }
 

osu.Game/Screens/Multi/Header.cs

@@ -22,7 +22,7 @@ namespace osu.Game.Screens.Multi
         private readonly OsuSpriteText screenType;
         private readonly HeaderBreadcrumbControl breadcrumbs;
 
-        public Header(Screen initialScreen)
+        public Header(ScreenStack stack)
         {
             RelativeSizeAxes = Axes.X;
             Height = HEIGHT;
@@ -75,7 +75,7 @@ namespace osu.Game.Screens.Multi
                                 },
                             },
                         },
-                        breadcrumbs = new HeaderBreadcrumbControl(initialScreen)
+                        breadcrumbs = new HeaderBreadcrumbControl(stack)
                         {
                             Anchor = Anchor.BottomLeft,
                             Origin = Anchor.BottomLeft,
@@ -103,8 +103,8 @@ namespace osu.Game.Screens.Multi
 
         private class HeaderBreadcrumbControl : ScreenBreadcrumbControl
         {
-            public HeaderBreadcrumbControl(Screen initialScreen)
-                : base(initialScreen)
+            public HeaderBreadcrumbControl(ScreenStack stack)
+                : base(stack)
             {
             }
 

osu.Game/Screens/Multi/IMultiplayerSubScreen.cs

@@ -3,7 +3,7 @@
 
 namespace osu.Game.Screens.Multi
 {
-    public interface IMultiplayerSubScreen
+    public interface IMultiplayerSubScreen : IOsuScreen
     {
         string ShortTitle { get; }
     }

osu.Game/Screens/Multi/Lounge/LoungeSubScreen.cs

@@ -37,7 +37,7 @@ namespace osu.Game.Screens.Multi.Lounge
 
             RoomInspector inspector;
 
-            Children = new Drawable[]
+            InternalChildren = new Drawable[]
             {
                 Filter = new FilterControl { Depth = -1 },
                 content = new Container
@@ -81,7 +81,7 @@ namespace osu.Game.Screens.Multi.Lounge
 
             Filter.Search.Current.ValueChanged += s => filterRooms();
             Filter.Tabs.Current.ValueChanged += t => filterRooms();
-            Filter.Search.Exit += Exit;
+            Filter.Search.Exit += this.Exit;
         }
 
         protected override void UpdateAfterChildren()
@@ -101,20 +101,20 @@ namespace osu.Game.Screens.Multi.Lounge
             GetContainingInputManager().ChangeFocus(Filter.Search);
         }
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             base.OnEntering(last);
             Filter.Search.HoldFocus = true;
         }
 
-        protected override bool OnExiting(Screen next)
+        public override bool OnExiting(IScreen next)
         {
             Filter.Search.HoldFocus = false;
             // no base call; don't animate
             return false;
         }
 
-        protected override void OnSuspending(Screen next)
+        public override void OnSuspending(IScreen next)
         {
             base.OnSuspending(next);
             Filter.Search.HoldFocus = false;
@@ -142,10 +142,10 @@ namespace osu.Game.Screens.Multi.Lounge
         public void Push(Room room)
         {
             // Handles the case where a room is clicked 3 times in quick succession
-            if (!IsCurrentScreen)
+            if (!this.IsCurrentScreen())
                 return;
 
-            Push(new MatchSubScreen(room, s => pushGameplayScreen?.Invoke(s)));
+            this.Push(new MatchSubScreen(room, s => pushGameplayScreen?.Invoke(s)));
         }
     }
 }

osu.Game/Screens/Multi/Match/MatchSubScreen.cs

@@ -55,7 +55,7 @@ namespace osu.Game.Screens.Multi.Match
             GridContainer bottomRow;
             MatchSettingsOverlay settings;
 
-            Children = new Drawable[]
+            InternalChildren = new Drawable[]
             {
                 new GridContainer
                 {
@@ -108,7 +108,7 @@ namespace osu.Game.Screens.Multi.Match
                 },
             };
 
-            header.OnRequestSelectBeatmap = () => Push(new MatchSongSelect { Selected = addPlaylistItem });
+            header.OnRequestSelectBeatmap = () => this.Push(new MatchSongSelect { Selected = addPlaylistItem });
             header.Tabs.Current.ValueChanged += t =>
             {
                 const float fade_duration = 500;
@@ -126,7 +126,7 @@ namespace osu.Game.Screens.Multi.Match
                 }
             };
 
-            chat.Exit += Exit;
+            chat.Exit += this.Exit;
         }
 
         [BackgroundDependencyLoader]
@@ -135,7 +135,7 @@ namespace osu.Game.Screens.Multi.Match
             beatmapManager.ItemAdded += beatmapAdded;
         }
 
-        protected override bool OnExiting(Screen next)
+        public override bool OnExiting(IScreen next)
         {
             manager?.PartRoom();
             return base.OnExiting(next);
@@ -194,11 +194,9 @@ namespace osu.Game.Screens.Multi.Match
             {
                 default:
                 case GameTypeTimeshift _:
-                    pushGameplayScreen?.Invoke(new PlayerLoader(() => {
-                        var player = new TimeshiftPlayer(room, room.Playlist.First().ID);
-                        player.Exited += _ => leaderboard.RefreshScores();
-
-                        return player;
+                    pushGameplayScreen?.Invoke(new PlayerLoader(() => new TimeshiftPlayer(room, room.Playlist.First().ID)
+                    {
+                        Exited = () => leaderboard.RefreshScores()
                     }));
                     break;
             }

osu.Game/Screens/Multi/Multiplayer.cs

@@ -28,12 +28,11 @@ namespace osu.Game.Screens.Multi
     {
         private readonly MultiplayerWaveContainer waves;
 
-        public override bool AllowBeatmapRulesetChange => currentSubScreen?.AllowBeatmapRulesetChange ?? base.AllowBeatmapRulesetChange;
+        public override bool AllowBeatmapRulesetChange => (screenStack.CurrentScreen as IMultiplayerSubScreen)?.AllowBeatmapRulesetChange ?? base.AllowBeatmapRulesetChange;
 
         private readonly OsuButton createButton;
         private readonly LoungeSubScreen loungeSubScreen;
-
-        private OsuScreen currentSubScreen;
+        private readonly ScreenStack screenStack;
 
         [Cached(Type = typeof(IRoomManager))]
         private RoomManager roomManager;
@@ -43,11 +42,13 @@ namespace osu.Game.Screens.Multi
 
         public Multiplayer()
         {
-            Child = waves = new MultiplayerWaveContainer
+            InternalChild = waves = new MultiplayerWaveContainer
             {
                 RelativeSizeAxes = Axes.Both,
             };
 
+            screenStack = new ScreenStack(loungeSubScreen = new LoungeSubScreen(this.Push)) { RelativeSizeAxes = Axes.Both };
+
             waves.AddRange(new Drawable[]
             {
                 new Container
@@ -74,9 +75,9 @@ namespace osu.Game.Screens.Multi
                 {
                     RelativeSizeAxes = Axes.Both,
                     Padding = new MarginPadding { Top = Header.HEIGHT },
-                    Child = loungeSubScreen = new LoungeSubScreen(Push),
+                    Child = screenStack
                 },
-                new Header(loungeSubScreen),
+                new Header(screenStack),
                 createButton = new HeaderButton
                 {
                     Anchor = Anchor.TopRight,
@@ -97,8 +98,8 @@ namespace osu.Game.Screens.Multi
                 roomManager = new RoomManager()
             });
 
-            screenAdded(loungeSubScreen);
-            loungeSubScreen.Exited += _ => Exit();
+            screenStack.ScreenPushed += screenPushed;
+            screenStack.ScreenExited += screenExited;
         }
 
         private readonly IBindable<bool> isIdle = new BindableBool();
@@ -120,7 +121,7 @@ namespace osu.Game.Screens.Multi
 
         private void updatePollingRate(bool idle)
         {
-            roomManager.TimeBetweenPolls = !IsCurrentScreen || !(currentSubScreen is LoungeSubScreen) ? 0 : (idle ? 120000 : 15000);
+            roomManager.TimeBetweenPolls = !this.IsCurrentScreen() || !(screenStack.CurrentScreen is LoungeSubScreen) ? 0 : (idle ? 120000 : 15000);
             Logger.Log($"Polling adjusted to {roomManager.TimeBetweenPolls}");
         }
 
@@ -133,28 +134,28 @@ namespace osu.Game.Screens.Multi
         private void forcefullyExit()
         {
             // This is temporary since we don't currently have a way to force screens to be exited
-            if (IsCurrentScreen)
-                Exit();
+            if (this.IsCurrentScreen())
+                this.Exit();
             else
             {
-                MakeCurrent();
+                this.MakeCurrent();
                 Schedule(forcefullyExit);
             }
         }
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
-            Content.FadeIn();
+            this.FadeIn();
 
             base.OnEntering(last);
             waves.Show();
         }
 
-        protected override bool OnExiting(Screen next)
+        public override bool OnExiting(IScreen next)
         {
             waves.Hide();
 
-            Content.Delay(WaveContainer.DISAPPEAR_DURATION).FadeOut();
+            this.Delay(WaveContainer.DISAPPEAR_DURATION).FadeOut();
 
             cancelLooping();
             loungeSubScreen.MakeCurrent();
@@ -163,20 +164,20 @@ namespace osu.Game.Screens.Multi
             return base.OnExiting(next);
         }
 
-        protected override void OnResuming(Screen last)
+        public override void OnResuming(IScreen last)
         {
             base.OnResuming(last);
 
-            Content.FadeIn(250);
-            Content.ScaleTo(1, 250, Easing.OutSine);
+            this.FadeIn(250);
+            this.ScaleTo(1, 250, Easing.OutSine);
 
             updatePollingRate(isIdle.Value);
         }
 
-        protected override void OnSuspending(Screen next)
+        public override void OnSuspending(IScreen next)
         {
-            Content.ScaleTo(1.1f, 250, Easing.InSine);
-            Content.FadeOut(250);
+            this.ScaleTo(1.1f, 250, Easing.InSine);
+            this.FadeOut(250);
 
             cancelLooping();
             roomManager.TimeBetweenPolls = 0;
@@ -202,9 +203,9 @@ namespace osu.Game.Screens.Multi
         {
             base.Update();
 
-            if (!IsCurrentScreen) return;
+            if (!this.IsCurrentScreen()) return;
 
-            if (currentSubScreen is MatchSubScreen)
+            if (screenStack.CurrentScreen is MatchSubScreen)
             {
                 var track = Beatmap.Value.Track;
                 if (track != null)
@@ -221,25 +222,18 @@ namespace osu.Game.Screens.Multi
 
                 createButton.Hide();
             }
-            else if (currentSubScreen is LoungeSubScreen)
+            else if (screenStack.CurrentScreen is LoungeSubScreen)
                 createButton.Show();
         }
 
-        private void screenAdded(Screen newScreen)
-        {
-            currentSubScreen = (OsuScreen)newScreen;
-            updatePollingRate(isIdle.Value);
+        private void screenPushed(IScreen lastScreen, IScreen newScreen)
+            => updatePollingRate(isIdle.Value);
 
-            newScreen.ModePushed += screenAdded;
-            newScreen.Exited += screenRemoved;
-        }
-
-        private void screenRemoved(Screen newScreen)
+        private void screenExited(IScreen lastScreen, IScreen newScreen)
         {
-            if (currentSubScreen is MatchSubScreen)
+            if (lastScreen is MatchSubScreen)
                 cancelLooping();
 
-            currentSubScreen = (OsuScreen)newScreen;
             updatePollingRate(isIdle.Value);
         }
 

osu.Game/Screens/Multi/MultiplayerSubScreen.cs

@@ -9,40 +9,40 @@ namespace osu.Game.Screens.Multi
 {
     public abstract class MultiplayerSubScreen : OsuScreen, IMultiplayerSubScreen
     {
-        protected virtual Drawable TransitionContent => Content;
+        protected virtual Drawable TransitionContent => this;
 
         public virtual string ShortTitle => Title;
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             base.OnEntering(last);
 
-            Content.FadeInFromZero(WaveContainer.APPEAR_DURATION, Easing.OutQuint);
+            this.FadeInFromZero(WaveContainer.APPEAR_DURATION, Easing.OutQuint);
             TransitionContent.FadeInFromZero(WaveContainer.APPEAR_DURATION, Easing.OutQuint);
             TransitionContent.MoveToX(200).MoveToX(0, WaveContainer.APPEAR_DURATION, Easing.OutQuint);
         }
 
-        protected override bool OnExiting(Screen next)
+        public override bool OnExiting(IScreen next)
         {
-            Content.FadeOut(WaveContainer.DISAPPEAR_DURATION, Easing.OutQuint);
+            this.FadeOut(WaveContainer.DISAPPEAR_DURATION, Easing.OutQuint);
             TransitionContent.MoveToX(200, WaveContainer.DISAPPEAR_DURATION, Easing.OutQuint);
 
             return base.OnExiting(next);
         }
 
-        protected override void OnResuming(Screen last)
+        public override void OnResuming(IScreen last)
         {
             base.OnResuming(last);
 
-            Content.FadeIn(WaveContainer.APPEAR_DURATION, Easing.OutQuint);
+            this.FadeIn(WaveContainer.APPEAR_DURATION, Easing.OutQuint);
             TransitionContent.MoveToX(0, WaveContainer.APPEAR_DURATION, Easing.OutQuint);
         }
 
-        protected override void OnSuspending(Screen next)
+        public override void OnSuspending(IScreen next)
         {
             base.OnSuspending(next);
 
-            Content.FadeOut(WaveContainer.DISAPPEAR_DURATION, Easing.OutQuint);
+            this.FadeOut(WaveContainer.DISAPPEAR_DURATION, Easing.OutQuint);
             TransitionContent.MoveToX(-200, WaveContainer.DISAPPEAR_DURATION, Easing.OutQuint);
         }
     }

osu.Game/Screens/Multi/Play/TimeshiftPlayer.cs

@@ -6,6 +6,7 @@ using System.Diagnostics;
 using System.Threading;
 using osu.Framework.Allocation;
 using osu.Framework.Logging;
+using osu.Framework.Screens;
 using osu.Game.Online.API;
 using osu.Game.Online.API.Requests;
 using osu.Game.Online.Multiplayer;
@@ -18,6 +19,8 @@ namespace osu.Game.Screens.Multi.Play
 {
     public class TimeshiftPlayer : Player
     {
+        public Action Exited;
+
         private readonly Room room;
         private readonly int playlistItemId;
 
@@ -50,7 +53,7 @@ namespace osu.Game.Screens.Multi.Play
                 Schedule(() =>
                 {
                     ValidForResume = false;
-                    Exit();
+                    this.Exit();
                 });
             };
 
@@ -60,6 +63,16 @@ namespace osu.Game.Screens.Multi.Play
                 Thread.Sleep(1000);
         }
 
+        public override bool OnExiting(IScreen next)
+        {
+            if (base.OnExiting(next))
+                return true;
+
+            Exited?.Invoke();
+
+            return false;
+        }
+
         protected override ScoreInfo CreateScore()
         {
             submitScore();
@@ -79,6 +92,13 @@ namespace osu.Game.Screens.Multi.Play
             api.Queue(request);
         }
 
+        protected override void Dispose(bool isDisposing)
+        {
+            base.Dispose(isDisposing);
+
+            Exited = null;
+        }
+
         protected override Results CreateResults(ScoreInfo score) => new MatchResults(score, room);
     }
 }

osu.Game/Screens/OsuScreen.cs

@@ -11,19 +11,17 @@ using osu.Framework.Graphics;
 using osu.Framework.Input.Bindings;
 using osu.Framework.Screens;
 using osu.Game.Beatmaps;
-using osu.Game.Graphics.Containers;
 using osu.Game.Input.Bindings;
 using osu.Game.Rulesets;
 using osu.Game.Screens.Menu;
-using osuTK;
 using osu.Game.Overlays;
 using osu.Framework.Graphics.Containers;
 
 namespace osu.Game.Screens
 {
-    public abstract class OsuScreen : Screen, IKeyBindingHandler<GlobalAction>, IHasDescription
+    public abstract class OsuScreen : Screen, IOsuScreen, IKeyBindingHandler<GlobalAction>, IHasDescription
     {
-        public BackgroundScreen Background { get; private set; }
+        public BackgroundScreen Background { get; }
 
         /// <summary>
         /// A user-facing title for this screen.
@@ -56,31 +54,31 @@ namespace osu.Game.Screens
         /// </summary>
         protected virtual OverlayActivation InitialOverlayActivationMode => OverlayActivation.All;
 
-        /// <summary>
-        /// Whether this <see cref="OsuScreen"/> allows the cursor to be displayed.
-        /// </summary>
         public virtual bool CursorVisible => true;
 
         protected new OsuGameBase Game => base.Game as OsuGameBase;
 
-        private OsuLogo logo;
+        [Resolved]
+        private OsuLogo logo { get; set; }
 
-        /// <summary>
-        /// Whether the beatmap or ruleset should be allowed to be changed by the user or game.
-        /// Used to mark exclusive areas where this is strongly prohibited, like gameplay.
-        /// </summary>
         public virtual bool AllowBeatmapRulesetChange => true;
 
         protected readonly Bindable<WorkingBeatmap> Beatmap = new Bindable<WorkingBeatmap>();
 
-        protected virtual float BackgroundParallaxAmount => 1;
-
-        private ParallaxContainer backgroundParallaxContainer;
+        public virtual float BackgroundParallaxAmount => 1;
 
         protected readonly Bindable<RulesetInfo> Ruleset = new Bindable<RulesetInfo>();
 
         private SampleChannel sampleExit;
 
+        protected OsuScreen()
+        {
+            Anchor = Anchor.Centre;
+            Origin = Anchor.Centre;
+
+            Background = CreateBackground();
+        }
+
         [BackgroundDependencyLoader(true)]
         private void load(BindableBeatmap beatmap, OsuGame osu, AudioManager audio, Bindable<RulesetInfo> ruleset)
         {
@@ -105,11 +103,11 @@ namespace osu.Game.Screens
 
         public virtual bool OnPressed(GlobalAction action)
         {
-            if (!IsCurrentScreen) return false;
+            if (!this.IsCurrentScreen()) return false;
 
             if (action == GlobalAction.Back && AllowBackButton)
             {
-                Exit();
+                this.Exit();
                 return true;
             }
 
@@ -118,7 +116,7 @@ namespace osu.Game.Screens
 
         public bool OnReleased(GlobalAction action) => action == GlobalAction.Back && AllowBackButton;
 
-        protected override void OnResuming(Screen last)
+        public override void OnResuming(IScreen last)
         {
             sampleExit?.Play();
             applyArrivingDefaults(true);
@@ -126,68 +124,24 @@ namespace osu.Game.Screens
             base.OnResuming(last);
         }
 
-        protected override void OnSuspending(Screen next)
+        public override void OnSuspending(IScreen next)
         {
             base.OnSuspending(next);
             onSuspendingLogo();
         }
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
-            OsuScreen lastOsu = last as OsuScreen;
-
-            BackgroundScreen bg = CreateBackground();
-
-            if (lastOsu?.Background != null)
-            {
-                backgroundParallaxContainer = lastOsu.backgroundParallaxContainer;
-
-                if (bg == null || lastOsu.Background.Equals(bg))
-                    //we can keep the previous mode's background.
-                    Background = lastOsu.Background;
-                else
-                {
-                    lastOsu.Background.Push(Background = bg);
-                }
-            }
-            else if (bg != null)
-            {
-                // this makes up for the fact our padding changes when the global toolbar is visible.
-                bg.Scale = new Vector2(1.06f);
-
-                AddInternal(backgroundParallaxContainer = new ParallaxContainer
-                {
-                    Depth = float.MaxValue,
-                    Children = new[]
-                    {
-                        Background = bg
-                    }
-                });
-            }
-
-            if ((logo = lastOsu?.logo) == null)
-                LoadComponentAsync(logo = new OsuLogo { Alpha = 0 }, AddInternal);
-
             applyArrivingDefaults(false);
 
             base.OnEntering(last);
         }
 
-        protected override bool OnExiting(Screen next)
+        public override bool OnExiting(IScreen next)
         {
             if (ValidForResume && logo != null)
                 onExitingLogo();
 
-            OsuScreen nextOsu = next as OsuScreen;
-
-            if (Background != null && !Background.Equals(nextOsu?.Background))
-            {
-                Background.Exit();
-
-                //We need to use MakeCurrent in case we are jumping up multiple game screens.
-                nextOsu?.Background?.MakeCurrent();
-            }
-
             if (base.OnExiting(next))
                 return true;
 
@@ -214,12 +168,9 @@ namespace osu.Game.Screens
         {
             logo.AppendAnimatingAction(() =>
             {
-                if (IsCurrentScreen) LogoArriving(logo, isResuming);
+                if (this.IsCurrentScreen()) LogoArriving(logo, isResuming);
             }, true);
 
-            if (backgroundParallaxContainer != null)
-                backgroundParallaxContainer.ParallaxAmount = ParallaxContainer.DEFAULT_PARALLAX_AMOUNT * BackgroundParallaxAmount;
-
             OverlayActivationMode.Value = InitialOverlayActivationMode;
 
             updateOverlayStates?.Invoke();
@@ -227,7 +178,7 @@ namespace osu.Game.Screens
 
         private void onExitingLogo()
         {
-            logo.AppendAnimatingAction(() => { LogoExiting(logo); }, false);
+            logo.AppendAnimatingAction(() => LogoExiting(logo), false);
         }
 
         /// <summary>
@@ -239,7 +190,7 @@ namespace osu.Game.Screens
 
         private void onSuspendingLogo()
         {
-            logo.AppendAnimatingAction(() => { LogoSuspending(logo); }, false);
+            logo.AppendAnimatingAction(() => LogoSuspending(logo), false);
         }
 
         /// <summary>

osu.Game/Screens/Play/Player.cs

@@ -40,7 +40,7 @@ namespace osu.Game.Screens.Play
     {
         protected override bool AllowBackButton => false; // handled by HoldForMenuButton
 
-        protected override float BackgroundParallaxAmount => 0.1f;
+        public override float BackgroundParallaxAmount => 0.1f;
 
         protected override bool HideOverlaysOnEnter => true;
 
@@ -166,7 +166,7 @@ namespace osu.Game.Screens.Play
             if (!ScoreProcessor.Mode.Disabled)
                 config.BindWith(OsuSetting.ScoreDisplayMode, ScoreProcessor.Mode);
 
-            Children = new Drawable[]
+            InternalChildren = new Drawable[]
             {
                 pauseContainer = new PauseContainer(offsetClock, adjustableClock)
                 {
@@ -225,7 +225,7 @@ namespace osu.Game.Screens.Play
                 {
                     Action = () =>
                     {
-                        if (!IsCurrentScreen) return;
+                        if (!this.IsCurrentScreen()) return;
 
                         fadeOut(true);
                         Restart();
@@ -260,18 +260,18 @@ namespace osu.Game.Screens.Play
 
         private void performUserRequestedExit()
         {
-            if (!IsCurrentScreen) return;
-            Exit();
+            if (!this.IsCurrentScreen()) return;
+            this.Exit();
         }
 
         public void Restart()
         {
-            if (!IsCurrentScreen) return;
+            if (!this.IsCurrentScreen()) return;
 
             sampleRestart?.Play();
             ValidForResume = false;
             RestartRequested?.Invoke();
-            Exit();
+            this.Exit();
         }
 
         private ScheduledDelegate onCompletionEvent;
@@ -290,13 +290,13 @@ namespace osu.Game.Screens.Play
             {
                 onCompletionEvent = Schedule(delegate
                 {
-                    if (!IsCurrentScreen) return;
+                    if (!this.IsCurrentScreen()) return;
 
                     var score = CreateScore();
                     if (RulesetContainer.ReplayScore == null)
                         scoreManager.Import(score, true);
 
-                    Push(CreateResults(score));
+                   this.Push(CreateResults(score));
 
                     onCompletionEvent = null;
                 });
@@ -331,15 +331,15 @@ namespace osu.Game.Screens.Play
             return true;
         }
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             base.OnEntering(last);
 
             if (!LoadedBeatmapSuccessfully)
                 return;
 
-            Content.Alpha = 0;
-            Content
+            Alpha = 0;
+            this
                 .ScaleTo(0.7f)
                 .ScaleTo(1, 750, Easing.OutQuint)
                 .Delay(250)
@@ -368,13 +368,13 @@ namespace osu.Game.Screens.Play
             pauseContainer.FadeIn(750, Easing.OutQuint);
         }
 
-        protected override void OnSuspending(Screen next)
+        public override void OnSuspending(IScreen next)
         {
             fadeOut();
             base.OnSuspending(next);
         }
 
-        protected override bool OnExiting(Screen next)
+        public override bool OnExiting(IScreen next)
         {
             if (onCompletionEvent != null)
             {
@@ -401,7 +401,7 @@ namespace osu.Game.Screens.Play
         private void fadeOut(bool instant = false)
         {
             float fadeOutDuration = instant ? 0 : 250;
-            Content.FadeOut(fadeOutDuration);
+            this.FadeOut(fadeOutDuration);
             Background?.FadeColour(Color4.White, fadeOutDuration, Easing.OutQuint);
         }
 
@@ -425,7 +425,7 @@ namespace osu.Game.Screens.Play
 
         protected override void UpdateBackgroundElements()
         {
-            if (!IsCurrentScreen) return;
+            if (!this.IsCurrentScreen()) return;
 
             base.UpdateBackgroundElements();
 

osu.Game/Screens/Play/PlayerLoader.cs

@@ -51,14 +51,14 @@ namespace osu.Game.Screens.Play
         [BackgroundDependencyLoader]
         private void load()
         {
-            Add(info = new BeatmapMetadataDisplay(Beatmap.Value)
+            AddInternal(info = new BeatmapMetadataDisplay(Beatmap.Value)
             {
                 Alpha = 0,
                 Anchor = Anchor.Centre,
                 Origin = Anchor.Centre,
             });
 
-            Add(new FillFlowContainer<PlayerSettingsGroup>
+            AddInternal(new FillFlowContainer<PlayerSettingsGroup>
             {
                 Anchor = Anchor.TopRight,
                 Origin = Anchor.TopRight,
@@ -78,7 +78,7 @@ namespace osu.Game.Screens.Play
 
         private void playerLoaded(Player player) => info.Loading = false;
 
-        protected override void OnResuming(Screen last)
+        public override void OnResuming(IScreen last)
         {
             base.OnResuming(last);
 
@@ -105,21 +105,21 @@ namespace osu.Game.Screens.Play
 
         private void contentIn()
         {
-            Content.ScaleTo(1, 650, Easing.OutQuint);
-            Content.FadeInFromZero(400);
+            this.ScaleTo(1, 650, Easing.OutQuint);
+            this.FadeInFromZero(400);
         }
 
         private void contentOut()
         {
-            Content.ScaleTo(0.7f, 300, Easing.InQuint);
-            Content.FadeOut(250);
+            this.ScaleTo(0.7f, 300, Easing.InQuint);
+            this.FadeOut(250);
         }
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             base.OnEntering(last);
 
-            Content.ScaleTo(0.7f);
+            this.ScaleTo(0.7f);
 
             contentIn();
 
@@ -170,7 +170,7 @@ namespace osu.Game.Screens.Play
 
         private void pushWhenLoaded()
         {
-            if (!IsCurrentScreen) return;
+            if (!this.IsCurrentScreen()) return;
 
             try
             {
@@ -191,7 +191,7 @@ namespace osu.Game.Screens.Play
 
                     this.Delay(250).Schedule(() =>
                     {
-                        if (!IsCurrentScreen) return;
+                        if (!this.IsCurrentScreen()) return;
 
                         loadTask = null;
 
@@ -200,9 +200,9 @@ namespace osu.Game.Screens.Play
                         ValidForResume = false;
 
                         if (player.LoadedBeatmapSuccessfully)
-                            Push(player);
+                            this.Push(player);
                         else
-                            Exit();
+                            this.Exit();
                     });
                 }, 500);
             }
@@ -218,15 +218,15 @@ namespace osu.Game.Screens.Play
             pushDebounce = null;
         }
 
-        protected override void OnSuspending(Screen next)
+        public override void OnSuspending(IScreen next)
         {
             base.OnSuspending(next);
             cancelLoad();
         }
 
-        protected override bool OnExiting(Screen next)
+        public override bool OnExiting(IScreen next)
         {
-            Content.ScaleTo(0.7f, 150, Easing.InQuint);
+            this.ScaleTo(0.7f, 150, Easing.InQuint);
             this.FadeOut(150);
             cancelLoad();
 

osu.Game/Screens/Play/ScreenWithBeatmapBackground.cs

@@ -40,7 +40,7 @@ namespace osu.Game.Screens.Play
             ShowStoryboard = config.GetBindable<bool>(OsuSetting.ShowStoryboard);
         }
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             base.OnEntering(last);
             DimLevel.ValueChanged += _ => UpdateBackgroundElements();
@@ -49,7 +49,7 @@ namespace osu.Game.Screens.Play
             InitializeBackgroundElements();
         }
 
-        protected override void OnResuming(Screen last)
+        public override void OnResuming(IScreen last)
         {
             base.OnResuming(last);
             InitializeBackgroundElements();
@@ -66,7 +66,7 @@ namespace osu.Game.Screens.Play
         /// <param name="userChange"></param>
         protected virtual void UpdateBackgroundElements()
         {
-            if (!IsCurrentScreen) return;
+            if (!this.IsCurrentScreen()) return;
 
             Background?.FadeColour(OsuColour.Gray(BackgroundOpacity), BACKGROUND_FADE_DURATION, Easing.OutQuint);
             Background?.BlurTo(new Vector2((float)BlurLevel.Value * 25), BACKGROUND_FADE_DURATION, Easing.OutQuint);

osu.Game/Screens/Ranking/Results.cs

@@ -55,7 +55,7 @@ namespace osu.Game.Screens.Ranking
 
         private IEnumerable<Drawable> allCircles => new Drawable[] { circleOuterBackground, circleInner, circleOuter };
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             base.OnEntering(last);
             (Background as BackgroundScreenBeatmap)?.BlurTo(background_blur, 2500, Easing.OutQuint);
@@ -98,7 +98,7 @@ namespace osu.Game.Screens.Ranking
             }
         }
 
-        protected override bool OnExiting(Screen next)
+        public override bool OnExiting(IScreen next)
         {
             allCircles.ForEach(c =>
             {
@@ -107,7 +107,7 @@ namespace osu.Game.Screens.Ranking
 
             Background.ScaleTo(1f, transition_time / 4, Easing.OutQuint);
 
-            Content.FadeOut(transition_time / 4);
+            this.FadeOut(transition_time / 4);
 
             return base.OnExiting(next);
         }
@@ -115,7 +115,7 @@ namespace osu.Game.Screens.Ranking
         [BackgroundDependencyLoader]
         private void load(OsuColour colours)
         {
-            Children = new Drawable[]
+            InternalChildren = new Drawable[]
             {
                 new AspectContainer
                 {
@@ -260,7 +260,7 @@ namespace osu.Game.Screens.Ranking
                 {
                     Anchor = Anchor.BottomLeft,
                     Origin = Anchor.BottomLeft,
-                    Action = Exit
+                    Action = this.Exit
                 },
             };
 

osu.Game/Screens/ScreenWhiteBox.cs

@@ -30,7 +30,7 @@ namespace osu.Game.Screens
 
         protected override BackgroundScreen CreateBackground() => new BackgroundScreenCustom(@"Backgrounds/bg2");
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             base.OnEntering(last);
 
@@ -38,51 +38,51 @@ namespace osu.Game.Screens
             if (last != null)
                 popButton.Alpha = 1;
 
-            Content.Alpha = 0;
+            Alpha = 0;
             textContainer.Position = new Vector2(DrawSize.X / 16, 0);
 
             boxContainer.ScaleTo(0.2f);
             boxContainer.RotateTo(-20);
 
-            using (Content.BeginDelayedSequence(300, true))
+            using (BeginDelayedSequence(300, true))
             {
                 boxContainer.ScaleTo(1, transition_time, Easing.OutElastic);
                 boxContainer.RotateTo(0, transition_time / 2, Easing.OutQuint);
 
                 textContainer.MoveTo(Vector2.Zero, transition_time, Easing.OutExpo);
-                Content.FadeIn(transition_time, Easing.OutExpo);
+                this.FadeIn(transition_time, Easing.OutExpo);
             }
         }
 
-        protected override bool OnExiting(Screen next)
+        public override bool OnExiting(IScreen next)
         {
             textContainer.MoveTo(new Vector2(DrawSize.X / 16, 0), transition_time, Easing.OutExpo);
-            Content.FadeOut(transition_time, Easing.OutExpo);
+            this.FadeOut(transition_time, Easing.OutExpo);
 
             return base.OnExiting(next);
         }
 
-        protected override void OnSuspending(Screen next)
+        public override void OnSuspending(IScreen next)
         {
             base.OnSuspending(next);
 
             textContainer.MoveTo(new Vector2(-(DrawSize.X / 16), 0), transition_time, Easing.OutExpo);
-            Content.FadeOut(transition_time, Easing.OutExpo);
+            this.FadeOut(transition_time, Easing.OutExpo);
         }
 
-        protected override void OnResuming(Screen last)
+        public override void OnResuming(IScreen last)
         {
             base.OnResuming(last);
 
             textContainer.MoveTo(Vector2.Zero, transition_time, Easing.OutExpo);
-            Content.FadeIn(transition_time, Easing.OutExpo);
+            this.FadeIn(transition_time, Easing.OutExpo);
         }
 
         public ScreenWhiteBox()
         {
             FillFlowContainer childModeButtons;
 
-            Children = new Drawable[]
+            InternalChildren = new Drawable[]
             {
                 boxContainer = new Container
                 {
@@ -148,7 +148,7 @@ namespace osu.Game.Screens
                     Anchor = Anchor.BottomLeft,
                     Origin = Anchor.BottomLeft,
                     Alpha = 0,
-                    Action = Exit
+                    Action = this.Exit
                 },
                 childModeButtons = new FillFlowContainer
                 {
@@ -171,7 +171,7 @@ namespace osu.Game.Screens
                         HoverColour = getColourFor(t).Lighten(0.2f),
                         Action = delegate
                         {
-                            Push(Activator.CreateInstance(t) as Screen);
+                           this.Push(Activator.CreateInstance(t) as Screen);
                         }
                     });
                 }

osu.Game/Screens/Select/EditSongSelect.cs

@@ -1,6 +1,8 @@
 // Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
+using osu.Framework.Screens;
+
 namespace osu.Game.Screens.Select
 {
     public class EditSongSelect : SongSelect
@@ -9,7 +11,7 @@ namespace osu.Game.Screens.Select
 
         protected override bool OnStart()
         {
-            Exit();
+            this.Exit();
             return true;
         }
     }

osu.Game/Screens/Select/MatchSongSelect.cs

@@ -3,6 +3,7 @@
 
 using System;
 using Humanizer;
+using osu.Framework.Screens;
 using osu.Game.Online.Multiplayer;
 using osu.Game.Screens.Multi;
 
@@ -28,8 +29,8 @@ namespace osu.Game.Screens.Select
 
             Selected?.Invoke(item);
 
-            if (IsCurrentScreen)
-                Exit();
+            if (this.IsCurrentScreen())
+                this.Exit();
 
             return true;
         }

osu.Game/Screens/Select/PlaySongSelect.cs

@@ -25,7 +25,7 @@ namespace osu.Game.Screens.Select
             }, Key.Number3);
         }
 
-        protected override void OnResuming(Screen last)
+        public override void OnResuming(IScreen last)
         {
             player = null;
 
@@ -64,7 +64,7 @@ namespace osu.Game.Screens.Select
 
             LoadComponentAsync(player = new PlayerLoader(() => new Player()), l =>
             {
-                if (IsCurrentScreen) Push(player);
+                if (this.IsCurrentScreen())this.Push(player);
             });
 
             return true;

osu.Game/Screens/Select/SongSelect.cs

@@ -88,7 +88,7 @@ namespace osu.Game.Screens.Select
             const float carousel_width = 640;
             const float filter_height = 100;
 
-            AddRange(new Drawable[]
+            AddRangeInternal(new Drawable[]
             {
                 new ParallaxContainer
                 {
@@ -156,8 +156,8 @@ namespace osu.Game.Screens.Select
                                 Background = { Width = 2 },
                                 Exit = () =>
                                 {
-                                    if (IsCurrentScreen)
-                                        Exit();
+                                    if (this.IsCurrentScreen())
+                                        this.Exit();
                                 },
                             },
                         }
@@ -182,7 +182,7 @@ namespace osu.Game.Screens.Select
 
             if (ShowFooter)
             {
-                Add(FooterPanels = new Container
+                AddInternal(FooterPanels = new Container
                 {
                     Anchor = Anchor.BottomLeft,
                     Origin = Anchor.BottomLeft,
@@ -193,7 +193,7 @@ namespace osu.Game.Screens.Select
                         Bottom = Footer.HEIGHT,
                     },
                 });
-                Add(Footer = new Footer
+                AddInternal(Footer = new Footer
                 {
                     OnBack = ExitFromBack,
                 });
@@ -210,7 +210,7 @@ namespace osu.Game.Screens.Select
                 });
             }
 
-            BeatmapDetails.Leaderboard.ScoreSelected += s => Push(new SoloResults(s));
+            BeatmapDetails.Leaderboard.ScoreSelected += s =>this.Push(new SoloResults(s));
         }
 
         [BackgroundDependencyLoader(true)]
@@ -281,13 +281,13 @@ namespace osu.Game.Screens.Select
                 return;
             }
 
-            Exit();
+            this.Exit();
         }
 
         public void Edit(BeatmapInfo beatmap = null)
         {
             Beatmap.Value = beatmaps.GetWorkingBeatmap(beatmap ?? beatmapNoDebounce);
-            Push(new Editor());
+           this.Push(new Editor());
         }
 
         /// <summary>
@@ -331,7 +331,7 @@ namespace osu.Game.Screens.Select
         {
             if (beatmap is DummyWorkingBeatmap) return;
 
-            if (IsCurrentScreen && !Carousel.SelectBeatmap(beatmap?.BeatmapInfo, false))
+            if (this.IsCurrentScreen() && !Carousel.SelectBeatmap(beatmap?.BeatmapInfo, false))
                 // If selecting new beatmap without bypassing filters failed, there's possibly a ruleset mismatch
                 if (beatmap?.BeatmapInfo?.Ruleset != null && beatmap.BeatmapInfo.Ruleset != Ruleset.Value)
                 {
@@ -411,7 +411,7 @@ namespace osu.Game.Screens.Select
                     }
                 }
 
-                if (IsCurrentScreen) ensurePlayingSelected(preview);
+                if (this.IsCurrentScreen()) ensurePlayingSelected(preview);
                 UpdateBeatmap(Beatmap.Value);
             }
 
@@ -431,11 +431,11 @@ namespace osu.Game.Screens.Select
                 Carousel.SelectNextRandom();
         }
 
-        protected override void OnEntering(Screen last)
+        public override void OnEntering(IScreen last)
         {
             base.OnEntering(last);
 
-            Content.FadeInFromZero(250);
+            this.FadeInFromZero(250);
             FilterControl.Activate();
         }
 
@@ -476,7 +476,7 @@ namespace osu.Game.Screens.Select
             logo.FadeOut(logo_transition / 2, Easing.Out);
         }
 
-        protected override void OnResuming(Screen last)
+        public override void OnResuming(IScreen last)
         {
             BeatmapDetails.Leaderboard.RefreshScores();
 
@@ -490,26 +490,26 @@ namespace osu.Game.Screens.Select
 
             base.OnResuming(last);
 
-            Content.FadeIn(250);
+            this.FadeIn(250);
 
-            Content.ScaleTo(1, 250, Easing.OutSine);
+            this.ScaleTo(1, 250, Easing.OutSine);
 
             FilterControl.Activate();
         }
 
-        protected override void OnSuspending(Screen next)
+        public override void OnSuspending(IScreen next)
         {
             ModSelect.Hide();
 
-            Content.ScaleTo(1.1f, 250, Easing.InSine);
+            this.ScaleTo(1.1f, 250, Easing.InSine);
 
-            Content.FadeOut(250);
+            this.FadeOut(250);
 
             FilterControl.Deactivate();
             base.OnSuspending(next);
         }
 
-        protected override bool OnExiting(Screen next)
+        public override bool OnExiting(IScreen next)
         {
             if (ModSelect.State == Visibility.Visible)
             {
@@ -521,7 +521,7 @@ namespace osu.Game.Screens.Select
 
             beatmapInfoWedge.State = Visibility.Hidden;
 
-            Content.FadeOut(100);
+            this.FadeOut(100);
 
             FilterControl.Deactivate();
 
@@ -627,7 +627,7 @@ namespace osu.Game.Screens.Select
 
         public override bool OnPressed(GlobalAction action)
         {
-            if (!IsCurrentScreen) return false;
+            if (!this.IsCurrentScreen()) return false;
 
             switch (action)
             {

osu.Game/Screens/Tournament/Drawings.cs

@@ -22,6 +22,7 @@ using osuTK;
 using osuTK.Graphics;
 using osu.Framework.IO.Stores;
 using osu.Framework.Graphics.Shapes;
+using osu.Framework.Screens;
 
 namespace osu.Game.Screens.Tournament
 {
@@ -70,13 +71,13 @@ namespace osu.Game.Screens.Tournament
 
             if (!TeamList.Teams.Any())
             {
-                Exit();
+                this.Exit();
                 return;
             }
 
             drawingsConfig = new DrawingsConfigManager(storage);
 
-            Children = new Drawable[]
+            InternalChildren = new Drawable[]
             {
                 new Box
                 {

osu.Game/Tests/Visual/ScreenTestCase.cs

@@ -28,16 +28,16 @@ namespace osu.Game.Tests.Visual
             {
                 nextScreen = screen;
 
-                if (IsCurrentScreen)
+                if (this.IsCurrentScreen())
                 {
-                    Push(screen);
+                   this.Push(screen);
                     nextScreen = null;
                 }
                 else
-                    MakeCurrent();
+                    this.MakeCurrent();
             });
 
-            protected override void OnResuming(Screen last)
+            public override void OnResuming(IScreen last)
             {
                 base.OnResuming(last);
                 if (nextScreen != null)

osu.Game/Tests/Visual/TestCasePlayer.cs

@@ -6,6 +6,7 @@ using System.Linq;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics.Shapes;
 using osu.Framework.Lists;
+using osu.Framework.Screens;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Mods;

osu.Game/osu.Game.csproj

@@ -12,13 +12,13 @@
   </ItemGroup>
   <ItemGroup Label="Project References">
     <ProjectReference Include="..\osu-resources\osu.Game.Resources\osu.Game.Resources.csproj" />
+    <ProjectReference Include="..\..\osu-framework\osu.Framework\osu.Framework.csproj" />
   </ItemGroup>
   <ItemGroup Label="Package References">
     <PackageReference Include="Humanizer" Version="2.5.16" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="2.2.1" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite.Core" Version="2.2.1" />
     <PackageReference Include="Newtonsoft.Json" Version="12.0.1" />
-    <PackageReference Include="ppy.osu.Framework" Version="2019.122.0" />
     <PackageReference Include="SharpCompress" Version="0.22.0" />
     <PackageReference Include="NUnit" Version="3.11.0" />
     <PackageReference Include="SharpRaven" Version="2.4.0" />

osu.sln

@@ -27,6 +27,10 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "osu.Game.Rulesets.Taiko.Tes
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "osu.Game.Rulesets.Osu.Tests", "osu.Game.Rulesets.Osu.Tests\osu.Game.Rulesets.Osu.Tests.csproj", "{6A2D5D58-0261-4A75-BE84-2BE8B076B7C2}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "osu.Framework", "..\osu-framework\osu.Framework\osu.Framework.csproj", "{93F341C2-AFA0-467F-B295-6639DD1A6249}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "osu.Framework.NativeLibs", "..\osu-framework\osu.Framework.NativeLibs\osu.Framework.NativeLibs.csproj", "{CB667825-98B9-4B86-B477-F67CD8E9E1CE}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -81,6 +85,14 @@ Global
 		{6A2D5D58-0261-4A75-BE84-2BE8B076B7C2}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{6A2D5D58-0261-4A75-BE84-2BE8B076B7C2}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{6A2D5D58-0261-4A75-BE84-2BE8B076B7C2}.Release|Any CPU.Build.0 = Release|Any CPU
+		{93F341C2-AFA0-467F-B295-6639DD1A6249}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{93F341C2-AFA0-467F-B295-6639DD1A6249}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{93F341C2-AFA0-467F-B295-6639DD1A6249}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{93F341C2-AFA0-467F-B295-6639DD1A6249}.Release|Any CPU.Build.0 = Release|Any CPU
+		{CB667825-98B9-4B86-B477-F67CD8E9E1CE}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{CB667825-98B9-4B86-B477-F67CD8E9E1CE}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{CB667825-98B9-4B86-B477-F67CD8E9E1CE}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{CB667825-98B9-4B86-B477-F67CD8E9E1CE}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE