Implement CurrentPage class

osu.Game/Graphics/UserInterface/PageSelector.cs

@@ -8,6 +8,9 @@ using osu.Framework.Bindables;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics.Shapes;
 using osu.Framework.Graphics.Sprites;
+using osu.Framework.Input.Events;
+using osu.Framework.Extensions.Color4Extensions;
+using System;
 
 namespace osu.Game.Graphics.UserInterface
 {
@@ -42,59 +45,144 @@ namespace osu.Game.Graphics.UserInterface
         {
             pillsFlow.Clear();
 
-            for (int i = 0; i < maxPages; i++)
+            for (int i = 1; i <= maxPages; i++)
             {
+                if (i == currentPage.Value)
+                    addCurrentPagePill();
+                else
                     addPagePill(i);
             }
         }
 
         private void addPagePill(int page)
         {
-            var pill = new Pill(page);
+            pillsFlow.Add(new Page(page.ToString(), () => currentPage.Value = page));
-
-            if (page != currentPage.Value)
-                pill.Action = () => currentPage.Value = page;
-
-            pillsFlow.Add(pill);
         }
 
-        private class Pill : OsuClickableContainer
+        private void addCurrentPagePill()
+        {
+            pillsFlow.Add(new CurrentPage(currentPage.Value.ToString()));
+        }
+
+        private abstract class DrawablePage : CompositeDrawable
         {
             private const int height = 20;
+            private const int margin = 8;
 
-            private readonly Box background;
+            protected readonly string Text;
 
-            public Pill(int page)
+            protected DrawablePage(string text)
             {
+                Text = text;
+
                 AutoSizeAxes = Axes.X;
                 Height = height;
-                Child = new CircularContainer
+
+                var background = CreateBackground();
+
+                if (background != null)
+                    AddInternal(background);
+
+                var content = CreateContent();
+                content.Margin = new MarginPadding { Horizontal = margin };
+
+                AddInternal(content);
+            }
+
+            protected abstract Drawable CreateContent();
+
+            protected virtual Drawable CreateBackground() => null;
+        }
+
+        private abstract class ActivatedDrawablePage : DrawablePage
         {
-                    AutoSizeAxes = Axes.X,
+            private readonly Action action;
-                    RelativeSizeAxes = Axes.Y,
+
-                    Masking = true,
+            public ActivatedDrawablePage(string text, Action action)
-                    Children = new Drawable[]
+                : base(text)
             {
-                        background = new Box
+                this.action = action;
+            }
+
+            protected override bool OnClick(ClickEvent e)
             {
-                            RelativeSizeAxes = Axes.Both,
+                action?.Invoke();
-                        },
+                return base.OnClick(e);
-                        new SpriteText
-                        {
-                            Anchor = Anchor.Centre,
-                            Origin = Anchor.Centre,
-                            Text = page.ToString(),
-                            Margin = new MarginPadding { Horizontal = 8 }
             }
         }
-                };
+
+        private class Page : ActivatedDrawablePage
+        {
+            private SpriteText text;
+
+            private OsuColour colours;
+
+            public Page(string text, Action action)
+                : base(text, action)
+            {
             }
 
             [BackgroundDependencyLoader]
             private void load(OsuColour colours)
             {
+                this.colours = colours;
+                text.Colour = colours.Seafoam;
+            }
+
+            protected override bool OnHover(HoverEvent e)
+            {
+                text.Colour = colours.Seafoam.Lighten(30f);
+                return base.OnHover(e);
+            }
+
+            protected override void OnHoverLost(HoverLostEvent e)
+            {
+                text.Colour = colours.Seafoam;
+                base.OnHoverLost(e);
+            }
+
+            protected override Drawable CreateContent() => text = new SpriteText
+            {
+                Anchor = Anchor.Centre,
+                Origin = Anchor.Centre,
+                Text = Text
+            };
+        }
+
+        private class CurrentPage : DrawablePage
+        {
+            private SpriteText text;
+
+            private Box background;
+
+            public CurrentPage(string text)
+                : base(text)
+            {
+            }
+
+            [BackgroundDependencyLoader]
+            private void load(OsuColour colours)
+            {
+                text.Colour = colours.GreySeafoam;
                 background.Colour = colours.Seafoam;
             }
+
+            protected override Drawable CreateContent() => text = new SpriteText
+            {
+                Anchor = Anchor.Centre,
+                Origin = Anchor.Centre,
+                Text = Text
+            };
+
+            protected override Drawable CreateBackground() => new CircularContainer
+            {
+                RelativeSizeAxes = Axes.Both,
+                Masking = true,
+                Child = background = new Box
+                {
+                    RelativeSizeAxes = Axes.Both,
+                }
+            };
         }
     }
 }