Add labelled dropdown component

osu.Game/Graphics/UserInterfaceV2/LabelledDropdown.cs

@@ -0,0 +1,29 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Collections.Generic;
+using osu.Framework.Graphics;
+using osu.Game.Graphics.UserInterface;
+
+namespace osu.Game.Graphics.UserInterfaceV2
+{
+    public class LabelledDropdown<T> : LabelledComponent<OsuDropdown<T>, T>
+    {
+        public LabelledDropdown()
+            : base(true)
+        {
+        }
+
+        public IEnumerable<T> Items
+        {
+            get => Component.Items;
+            set => Component.Items = value;
+        }
+
+        protected override OsuDropdown<T> CreateComponent() => new OsuDropdown<T>
+        {
+            RelativeSizeAxes = Axes.X,
+            Width = 0.5f,
+        };
+    }
+}