Add some xmldocs

osu.Game/Collections/DrawableCollectionList.cs

@@ -10,6 +10,9 @@ using osuTK;
 
 namespace osu.Game.Collections
 {
+    /// <summary>
+    /// Visualises a list of <see cref="BeatmapCollection"/>s.
+    /// </summary>
     public class DrawableCollectionList : OsuRearrangeableListContainer<BeatmapCollection>
     {
         private Scroll scroll;
@@ -29,8 +32,18 @@ namespace osu.Game.Collections
             return new DrawableCollectionListItem(item, true);
         }
 
+        /// <summary>
+        /// The scroll container for this <see cref="DrawableCollectionList"/>.
+        /// Contains the main flow of <see cref="DrawableCollectionListItem"/> and attaches a placeholder item to the end of the list.
+        /// </summary>
+        /// <remarks>
+        /// Use <see cref="ReplacePlaceholder"/> to transfer the placeholder into the main list.
+        /// </remarks>
         private class Scroll : OsuScrollContainer
         {
+            /// <summary>
+            /// The currently-displayed placeholder item.
+            /// </summary>
             public DrawableCollectionListItem PlaceholderItem { get; private set; }
 
             protected override Container<Drawable> Content => content;
@@ -74,6 +87,7 @@ namespace osu.Game.Collections
             /// <summary>
             /// Replaces the current <see cref="PlaceholderItem"/> with a new one, and returns the previous.
             /// </summary>
+            /// <returns>The current <see cref="PlaceholderItem"/>.</returns>
             public DrawableCollectionListItem ReplacePlaceholder()
             {
                 var previous = PlaceholderItem;
@@ -85,6 +99,9 @@ namespace osu.Game.Collections
             }
         }
 
+        /// <summary>
+        /// The flow of <see cref="DrawableCollectionListItem"/>. Disables layout easing unless a drag is in progress.
+        /// </summary>
         private class Flow : FillFlowContainer<RearrangeableListItem<BeatmapCollection>>
         {
             public readonly IBindable<bool> DragActive = new Bindable<bool>();

osu.Game/Collections/DrawableCollectionListItem.cs

@@ -19,6 +19,9 @@ using osuTK.Graphics;
 
 namespace osu.Game.Collections
 {
+    /// <summary>
+    /// Visualises a <see cref="BeatmapCollection"/> inside a <see cref="DrawableCollectionList"/>.
+    /// </summary>
     public class DrawableCollectionListItem : OsuRearrangeableListItem<BeatmapCollection>
     {
         private const float item_height = 35;
@@ -26,6 +29,11 @@ namespace osu.Game.Collections
 
         private readonly Bindable<bool> isCreated = new Bindable<bool>();
 
+        /// <summary>
+        /// Creates a new <see cref="DrawableCollectionListItem"/>.
+        /// </summary>
+        /// <param name="item">The <see cref="BeatmapCollection"/>.</param>
+        /// <param name="isCreated">Whether <paramref name="item"/> currently exists inside the <see cref="BeatmapCollectionManager"/>.</param>
         public DrawableCollectionListItem(BeatmapCollection item, bool isCreated)
             : base(item)
         {
@@ -39,6 +47,9 @@ namespace osu.Game.Collections
             IsCreated = { BindTarget = isCreated }
         };
 
+        /// <summary>
+        /// The main content of the <see cref="DrawableCollectionListItem"/>.
+        /// </summary>
         private class ItemContent : CircularContainer
         {
             public readonly Bindable<bool> IsCreated = new Bindable<bool>();