Add FocusedTextBox abstraction.

osu.Game/Graphics/UserInterface/FocusedTextBox.cs

@@ -0,0 +1,49 @@
+using OpenTK.Graphics;
+using OpenTK.Input;
+using osu.Framework.Input;
+using System;
+using System.Linq;
+
+namespace osu.Game.Graphics.UserInterface
+{
+    public class FocusedTextBox : OsuTextBox
+    {
+        protected override Color4 BackgroundUnfocused => new Color4(10, 10, 10, 255);
+        protected override Color4 BackgroundFocused => new Color4(10, 10, 10, 255);
+
+        public Action Exit;
+
+        private bool focus;
+        public bool HoldFocus
+        {
+            get { return focus; }
+            set
+            {
+                focus = value;
+                if (!focus)
+                    TriggerFocusLost();
+            }
+        }
+
+        protected override bool OnFocus(InputState state)
+        {
+            var result = base.OnFocus(state);
+            BorderThickness = 0;
+            return result;
+        }
+
+        protected override void OnFocusLost(InputState state)
+        {
+            if (state.Keyboard.Keys.Any(key => key == Key.Escape))
+            {
+                if (Text.Length > 0)
+                    Text = string.Empty;
+                else
+                    Exit?.Invoke();
+            }
+            base.OnFocusLost(state);
+        }
+
+        public override bool RequestingFocus => HoldFocus;
+    }
+}

osu.Game/Graphics/UserInterface/OsuTextBox.cs

@@ -8,7 +8,6 @@ using osu.Framework.Graphics.Sprites;
 using osu.Framework.Graphics.UserInterface;
 using osu.Framework.Input;
 using osu.Game.Graphics.Sprites;
-using osu.Game.Overlays;
 using OpenTK.Graphics;
 
 namespace osu.Game.Graphics.UserInterface

osu.Game/Screens/Select/FilterControl.cs

@@ -47,18 +47,19 @@ namespace osu.Game.Screens.Select
                     Direction = FlowDirections.Vertical,
                     Children = new Drawable[]
                     {
-                        searchTextBox = new SearchTextBox { RelativeSizeAxes = Axes.X },
+                        searchTextBox = new SearchTextBox {
+                            RelativeSizeAxes = Axes.X,
+                            OnChange = (TextBox sender, bool newText) =>
+                            {
+                                if (newText)
+                                    FilterChanged?.Invoke();
+                            },
+                            Exit = () => Exit?.Invoke(),
+                        },
                         new GroupSortTabs()
                     }
                 }
             };
-
-            searchTextBox.OnChange += (TextBox sender, bool newText) =>
-            {
-                if (newText)
-                    FilterChanged?.Invoke();
-            };
-            searchTextBox.Exit = () => Exit?.Invoke();
         }
 
         public void Deactivate()

osu.Game/Screens/Select/SearchTextBox.cs

@@ -16,26 +16,8 @@ namespace osu.Game.Screens.Select
     /// <summary>
     /// A textbox which holds focus eagerly.
     /// </summary>
-    public class SearchTextBox : OsuTextBox
+    public class SearchTextBox : FocusedTextBox
     {
-        protected override Color4 BackgroundUnfocused => new Color4(10, 10, 10, 255);
-        protected override Color4 BackgroundFocused => new Color4(10, 10, 10, 255);
-        public Action Exit;
-
-        private bool focus;
-        public bool HoldFocus
-        {
-            get { return focus; }
-            set
-            {
-                focus = value;
-                if (!focus)
-                    TriggerFocusLost();
-            }
-        }
-
-        public override bool RequestingFocus => HoldFocus;
-
         public SearchTextBox()
         {
             Height = 35;
@@ -53,25 +35,6 @@ namespace osu.Game.Screens.Select
             PlaceholderText = "type to search";
         }
 
-        protected override bool OnFocus(InputState state)
-        {
-            var result = base.OnFocus(state);
-            BorderThickness = 0;
-            return result;
-        }
-
-        protected override void OnFocusLost(InputState state)
-        {
-            if (state.Keyboard.Keys.Any(key => key == Key.Escape))
-            {
-                if (Text.Length > 0)
-                    Text = string.Empty;
-                else
-                    Exit?.Invoke();
-            }
-            base.OnFocusLost(state);
-        }
-
         protected override bool OnKeyDown(InputState state, KeyDownEventArgs args)
         {
             if (HandlePendingText(state)) return true;

osu.Game/osu.Game.csproj

@@ -70,6 +70,7 @@
     <Compile Include="Graphics\Cursor\CursorTrail.cs" />
     <Compile Include="Graphics\Sprites\OsuSpriteText.cs" />
     <Compile Include="Graphics\UserInterface\BackButton.cs" />
+    <Compile Include="Graphics\UserInterface\FocusedTextBox.cs" />
     <Compile Include="Graphics\UserInterface\Nub.cs" />
     <Compile Include="Graphics\UserInterface\OsuPasswordTextBox.cs" />
     <Compile Include="Graphics\UserInterface\OsuSliderBar.cs" />