Merge pull request #1202 from 2yangk23/rearrange-playlist

Rearranging support in playlist

osu.Game/Overlays/Music/PlaylistItem.cs

@@ -8,6 +8,7 @@ using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Sprites;
+using osu.Framework.Input;
 using osu.Framework.Localisation;
 using osu.Game.Beatmaps;
 using osu.Game.Graphics;
@@ -16,7 +17,7 @@ using OpenTK;
 
 namespace osu.Game.Overlays.Music
 {
-    internal class PlaylistItem : Container, IFilterable
+    internal class PlaylistItem : Container, IFilterable, IDraggable
     {
         private const float fade_duration = 100;
 
@@ -33,6 +34,8 @@ namespace osu.Game.Overlays.Music
 
         public Action<BeatmapSetInfo> OnSelect;
 
+        public bool IsDraggable => handle.IsHovered;
+
         private bool selected;
         public bool Selected
         {
@@ -68,15 +71,9 @@ namespace osu.Game.Overlays.Music
 
             Children = new Drawable[]
             {
-                handle = new SpriteIcon
+                handle = new PlaylistItemHandle
                 {
-                    Anchor = Anchor.TopLeft,
+                    Colour = colours.Gray5
-                    Origin = Anchor.TopLeft,
-                    Size = new Vector2(12),
-                    Colour = colours.Gray5,
-                    Icon = FontAwesome.fa_bars,
-                    Alpha = 0f,
-                    Margin = new MarginPadding { Left = 5, Top = 2 },
                 },
                 text = new OsuTextFlowContainer
                 {
@@ -114,19 +111,19 @@ namespace osu.Game.Overlays.Music
             });
         }
 
-        protected override bool OnHover(Framework.Input.InputState state)
+        protected override bool OnHover(InputState state)
         {
             handle.FadeIn(fade_duration);
 
             return base.OnHover(state);
         }
 
-        protected override void OnHoverLost(Framework.Input.InputState state)
+        protected override void OnHoverLost(InputState state)
         {
             handle.FadeOut(fade_duration);
         }
 
-        protected override bool OnClick(Framework.Input.InputState state)
+        protected override bool OnClick(InputState state)
         {
             OnSelect?.Invoke(BeatmapSetInfo);
             return true;
@@ -148,5 +145,27 @@ namespace osu.Game.Overlays.Music
                 this.FadeTo(matching ? 1 : 0, 200);
             }
         }
+
+        private class PlaylistItemHandle : SpriteIcon
+        {
+
+            public PlaylistItemHandle()
+            {
+                Anchor = Anchor.TopLeft;
+                Origin = Anchor.TopLeft;
+                Size = new Vector2(12);
+                Icon = FontAwesome.fa_bars;
+                Alpha = 0f;
+                Margin = new MarginPadding { Left = 5, Top = 2 };
+            }
+        }
+    }
+
+    public interface IDraggable : IDrawable
+    {
+        /// <summary>
+        /// Whether this <see cref="IDraggable"/> can be dragged in its current state.
+        /// </summary>
+        bool IsDraggable { get; }
     }
 }

osu.Game/Overlays/Music/PlaylistList.cs

@@ -4,55 +4,63 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using osu.Framework.Extensions.IEnumerableExtensions;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
+using osu.Framework.Input;
 using osu.Game.Beatmaps;
 using osu.Game.Graphics.Containers;
+using OpenTK;
 
 namespace osu.Game.Overlays.Music
 {
-    internal class PlaylistList : Container
+    internal class PlaylistList : CompositeDrawable
     {
-        private readonly FillFlowContainer<PlaylistItem> items;
-
-        public IEnumerable<BeatmapSetInfo> BeatmapSets
-        {
-            set
-            {
-                items.Children = value.Select(item => new PlaylistItem(item) { OnSelect = itemSelected }).ToList();
-            }
-        }
-
-        public BeatmapSetInfo FirstVisibleSet => items.Children.FirstOrDefault(i => i.MatchingFilter)?.BeatmapSetInfo;
-
-        private void itemSelected(BeatmapSetInfo b)
-        {
-            OnSelect?.Invoke(b);
-        }
-
         public Action<BeatmapSetInfo> OnSelect;
 
-        private readonly SearchContainer search;
+        private readonly ItemsScrollContainer items;
-
-        public void Filter(string searchTerm) => search.SearchTerm = searchTerm;
-
-        public BeatmapSetInfo SelectedItem
-        {
-            get { return items.Children.FirstOrDefault(i => i.Selected)?.BeatmapSetInfo; }
-            set
-            {
-                foreach (PlaylistItem s in items.Children)
-                    s.Selected = s.BeatmapSetInfo.ID == value?.ID;
-            }
-        }
 
         public PlaylistList()
         {
-            Children = new Drawable[]
+            InternalChild = items = new ItemsScrollContainer
-            {
-                new OsuScrollContainer
             {
                 RelativeSizeAxes = Axes.Both,
+                OnSelect = set => OnSelect?.Invoke(set)
+            };
+        }
+
+        public new MarginPadding Padding
+        {
+            get { return base.Padding; }
+            set { base.Padding = value; }
+        }
+
+        public IEnumerable<BeatmapSetInfo> BeatmapSets { set { items.Sets = value; } }
+
+        public BeatmapSetInfo FirstVisibleSet => items.FirstVisibleSet;
+        public BeatmapSetInfo NextSet => items.NextSet;
+        public BeatmapSetInfo PreviousSet => items.PreviousSet;
+
+        public BeatmapSetInfo SelectedSet
+        {
+            get { return items.SelectedSet; }
+            set { items.SelectedSet = value; }
+        }
+
+        public void AddBeatmapSet(BeatmapSetInfo beatmapSet) => items.AddBeatmapSet(beatmapSet);
+        public bool RemoveBeatmapSet(BeatmapSetInfo beatmapSet) => items.RemoveBeatmapSet(beatmapSet);
+
+        public void Filter(string searchTerm) => items.SearchTerm = searchTerm;
+
+        private class ItemsScrollContainer : OsuScrollContainer
+        {
+            public Action<BeatmapSetInfo> OnSelect;
+
+            private readonly SearchContainer search;
+            private readonly FillFlowContainer<PlaylistItem> items;
+
+            public ItemsScrollContainer()
+            {
                 Children = new Drawable[]
                 {
                     search = new SearchContainer
@@ -68,22 +76,157 @@ namespace osu.Game.Overlays.Music
                             },
                         }
                     }
-                    },
-                },
                 };
             }
 
+            public IEnumerable<BeatmapSetInfo> Sets
+            {
+                set
+                {
+                    items.Clear();
+                    value.ForEach(AddBeatmapSet);
+                }
+            }
+
+            public string SearchTerm
+            {
+                get { return search.SearchTerm; }
+                set { search.SearchTerm = value; }
+            }
+
             public void AddBeatmapSet(BeatmapSetInfo beatmapSet)
             {
-            items.Add(new PlaylistItem(beatmapSet) { OnSelect = itemSelected });
+                items.Add(new PlaylistItem(beatmapSet)
+                {
+                    OnSelect = set => OnSelect?.Invoke(set),
+                    Depth = items.Count
+                });
             }
 
-        public void RemoveBeatmapSet(BeatmapSetInfo beatmapSet)
+            public bool RemoveBeatmapSet(BeatmapSetInfo beatmapSet)
             {
-            PlaylistItem itemToRemove = items.Children.FirstOrDefault(item => item.BeatmapSetInfo.ID == beatmapSet.ID);
+                var itemToRemove = items.FirstOrDefault(i => i.BeatmapSetInfo.ID == beatmapSet.ID);
-            if (itemToRemove != null) items.Remove(itemToRemove);
+                if (itemToRemove == null)
+                    return false;
+                return items.Remove(itemToRemove);
             }
 
+            public BeatmapSetInfo SelectedSet
+            {
+                get { return items.FirstOrDefault(i => i.Selected)?.BeatmapSetInfo; }
+                set
+                {
+                    foreach (PlaylistItem s in items.Children)
+                        s.Selected = s.BeatmapSetInfo.ID == value?.ID;
+                }
+            }
+
+            public BeatmapSetInfo FirstVisibleSet => items.FirstOrDefault(i => i.MatchingFilter)?.BeatmapSetInfo;
+            public BeatmapSetInfo NextSet => (items.SkipWhile(i => !i.Selected).Skip(1).FirstOrDefault() ?? items.FirstOrDefault())?.BeatmapSetInfo;
+            public BeatmapSetInfo PreviousSet => (items.TakeWhile(i => !i.Selected).LastOrDefault() ?? items.LastOrDefault())?.BeatmapSetInfo;
+
+            private Vector2 nativeDragPosition;
+            private PlaylistItem draggedItem;
+
+            protected override bool OnDragStart(InputState state)
+            {
+                nativeDragPosition = state.Mouse.NativeState.Position;
+                draggedItem = items.FirstOrDefault(d => d.IsDraggable);
+                return draggedItem != null || base.OnDragStart(state);
+            }
+
+            protected override bool OnDrag(InputState state)
+            {
+                nativeDragPosition = state.Mouse.NativeState.Position;
+                if (draggedItem == null)
+                    return base.OnDrag(state);
+                return true;
+            }
+
+            protected override bool OnDragEnd(InputState state)
+            {
+                nativeDragPosition = state.Mouse.NativeState.Position;
+                var handled = draggedItem != null || base.OnDragEnd(state);
+                draggedItem = null;
+
+                return handled;
+            }
+
+            protected override void Update()
+            {
+                base.Update();
+
+                if (draggedItem == null)
+                    return;
+
+                updateScrollPosition();
+                updateDragPosition();
+            }
+
+            private void updateScrollPosition()
+            {
+                const float start_offset = 10;
+                const double max_power = 50;
+                const double exp_base = 1.05;
+
+                var localPos = ToLocalSpace(nativeDragPosition);
+
+                if (localPos.Y < start_offset)
+                {
+                    if (Current <= 0)
+                        return;
+
+                    var power = Math.Min(max_power, Math.Abs(start_offset - localPos.Y));
+                    ScrollBy(-(float)Math.Pow(exp_base, power));
+                }
+                else if (localPos.Y > DrawHeight - start_offset)
+                {
+                    if (IsScrolledToEnd())
+                        return;
+
+                    var power = Math.Min(max_power, Math.Abs(DrawHeight - start_offset - localPos.Y));
+                    ScrollBy((float)Math.Pow(exp_base, power));
+                }
+            }
+
+            private void updateDragPosition()
+            {
+                var itemsPos = items.ToLocalSpace(nativeDragPosition);
+
+                int srcIndex = (int)draggedItem.Depth;
+
+                // Find the last item with position < mouse position. Note we can't directly use
+                // the item positions as they are being transformed
+                float heightAccumulator = 0;
+                int dstIndex = 0;
+                for (; dstIndex < items.Count; dstIndex++)
+                {
+                    // Using BoundingBox here takes care of scale, paddings, etc...
+                    heightAccumulator += items[dstIndex].BoundingBox.Height;
+                    if (heightAccumulator > itemsPos.Y)
+                        break;
+                }
+
+                dstIndex = MathHelper.Clamp(dstIndex, 0, items.Count - 1);
+
+                if (srcIndex == dstIndex)
+                    return;
+
+                if (srcIndex < dstIndex)
+                {
+                    for (int i = srcIndex + 1; i <= dstIndex; i++)
+                        items.ChangeChildDepth(items[i], i - 1);
+                }
+                else
+                {
+                    for (int i = dstIndex; i < srcIndex; i++)
+                        items.ChangeChildDepth(items[i], i + 1);
+                }
+
+                items.ChangeChildDepth(draggedItem, dstIndex);
+            }
+
+
             private class ItemSearchContainer : FillFlowContainer<PlaylistItem>, IHasFilterableChildren
             {
                 public string[] FilterTerms => new string[] { };
@@ -96,6 +239,9 @@ namespace osu.Game.Overlays.Music
                     }
                 }
 
+                // Compare with reversed ChildID and Depth
+                protected override int Compare(Drawable x, Drawable y) => base.Compare(y, x);
+
                 public IEnumerable<IFilterable> FilterableChildren => Children;
 
                 public ItemSearchContainer()
@@ -105,4 +251,5 @@ namespace osu.Game.Overlays.Music
                 }
             }
         }
+    }
 }

osu.Game/Overlays/Music/PlaylistOverlay.cs

@@ -92,7 +92,7 @@ namespace osu.Game.Overlays.Music
         protected override void LoadComplete()
         {
             base.LoadComplete();
-            beatmapBacking.ValueChanged += b => list.SelectedItem = b?.BeatmapSetInfo;
+            beatmapBacking.ValueChanged += b => list.SelectedSet = b?.BeatmapSetInfo;
             beatmapBacking.TriggerChange();
         }
 
@@ -126,24 +126,24 @@ namespace osu.Game.Overlays.Music
 
         public void PlayPrevious()
         {
-            var currentID = beatmapBacking.Value?.BeatmapSetInfo.ID ?? -1;
+            var playable = list.PreviousSet;
-            var available = BeatmapSets.Reverse();
-
-            var playable = available.SkipWhile(b => b.ID != currentID).Skip(1).FirstOrDefault() ?? available.FirstOrDefault();
 
             if (playable != null)
+            {
                 playSpecified(playable.Beatmaps[0]);
+                list.SelectedSet = playable;
+            }
         }
 
         public void PlayNext()
         {
-            var currentID = beatmapBacking.Value?.BeatmapSetInfo.ID ?? -1;
+            var playable = list.NextSet;
-            var available = BeatmapSets;
-
-            var playable = available.SkipWhile(b => b.ID != currentID).Skip(1).FirstOrDefault() ?? available.FirstOrDefault();
 
             if (playable != null)
+            {
                 playSpecified(playable.Beatmaps[0]);
+                list.SelectedSet = playable;
+            }
         }
 
         private void playSpecified(BeatmapInfo info)