Add basic mod preset column implementation

osu.Game/Overlays/Mods/ModPresetColumn.cs

@@ -0,0 +1,77 @@
+// 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;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+using osu.Framework.Allocation;
+using osu.Game.Graphics;
+using osu.Game.Localisation;
+using osu.Game.Rulesets.Mods;
+using osuTK;
+
+namespace osu.Game.Overlays.Mods
+{
+    public class ModPresetColumn : ModSelectColumn
+    {
+        private IReadOnlyList<ModPreset> presets = Array.Empty<ModPreset>();
+
+        /// <summary>
+        /// Sets the collection of available mod presets.
+        /// </summary>
+        public IReadOnlyList<ModPreset> Presets
+        {
+            get => presets;
+            set
+            {
+                presets = value;
+
+                if (IsLoaded)
+                    asyncLoadPanels();
+            }
+        }
+
+        [BackgroundDependencyLoader]
+        private void load(OsuColour colours)
+        {
+            AccentColour = colours.Orange1;
+            HeaderText = ModPresetColumnStrings.PersonalPresets;
+        }
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            asyncLoadPanels();
+        }
+
+        private CancellationTokenSource? cancellationTokenSource;
+
+        private Task? latestLoadTask;
+        internal bool ItemsLoaded => latestLoadTask == null;
+
+        private void asyncLoadPanels()
+        {
+            cancellationTokenSource?.Cancel();
+
+            var panels = presets.Select(preset => new ModPresetPanel(preset)
+            {
+                Shear = Vector2.Zero
+            });
+
+            Task? loadTask;
+
+            latestLoadTask = loadTask = LoadComponentsAsync(panels, loaded =>
+            {
+                ItemsFlow.ChildrenEnumerable = loaded;
+            }, (cancellationTokenSource = new CancellationTokenSource()).Token);
+            loadTask.ContinueWith(_ =>
+            {
+                if (loadTask == latestLoadTask)
+                    latestLoadTask = null;
+            });
+        }
+    }
+}