Make Header and it's components updateable.

osu.Game/Overlays/OnlineBeatmapSet/AuthorInfo.cs

@@ -16,20 +16,53 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
     {
         private const float height = 50;
 
-        public AuthorInfo(BeatmapSetOnlineInfo info)
+        private readonly UpdateableAvatar avatar;
+        private readonly FillFlowContainer fields;
+
+        private BeatmapSetInfo beatmapSet;
+        public BeatmapSetInfo BeatmapSet
+        {
+            get { return beatmapSet; }
+            set
+            {
+                if (value == beatmapSet) return;
+                beatmapSet = value;
+
+                var i = BeatmapSet.OnlineInfo;
+
+                avatar.User = i.Author;
+                fields.Children = new Drawable[]
+                {
+                    new Field("made by", i.Author.Username, @"Exo2.0-RegularItalic"),
+                    new Field("submitted on", i.Submitted.ToString(@"MMM d, yyyy"), @"Exo2.0-Bold")
+                    {
+                        Margin = new MarginPadding { Top = 5 },
+                    },
+                };
+
+                if (i.Ranked.HasValue)
+                {
+                    fields.Add(new Field("ranked on ", i.Ranked.Value.ToString(@"MMM d, yyyy"), @"Exo2.0-Bold"));
+                }
+                else if (i.LastUpdated.HasValue)
+                {
+                    fields.Add(new Field("last updated on ", i.LastUpdated.Value.ToString(@"MMM d, yyyy"), @"Exo2.0-Bold"));
+                }
+            }
+        }
+
+        public AuthorInfo()
         {
             RelativeSizeAxes = Axes.X;
             Height = height;
 
-            FillFlowContainer fields;
             Children = new Drawable[]
             {
-                new UpdateableAvatar
+                avatar = new UpdateableAvatar
                 {
                     Size = new Vector2(height),
                     CornerRadius = 3,
                     Masking = true,
-                    User = info.Author,
                     EdgeEffect = new EdgeEffectParameters
                     {
                         Colour = Color4.Black.Opacity(0.25f),
@@ -43,25 +76,8 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
                     RelativeSizeAxes = Axes.Both,
                     Direction = FillDirection.Vertical,
                     Padding = new MarginPadding { Left = height + 5 },
-                    Children = new Drawable[]
-                    {
-                        new Field("made by", info.Author.Username, @"Exo2.0-RegularItalic"),
-                        new Field("submitted on", info.Submitted.ToString(@"MMM d, yyyy"), @"Exo2.0-Bold")
-                        {
-                            Margin = new MarginPadding { Top = 5 },
-                        },
-                    },
                 },
             };
-
-            if (info.Ranked.HasValue)
-            {
-                fields.Add(new Field("ranked on ", info.Ranked.Value.ToString(@"MMM d, yyyy"), @"Exo2.0-Bold"));
-            }
-            else if (info.LastUpdated.HasValue)
-            {
-                fields.Add(new Field("last updated on ", info.LastUpdated.Value.ToString(@"MMM d, yyyy"), @"Exo2.0-Bold"));
-            }
         }
 
         private class Field : FillFlowContainer

osu.Game/Overlays/OnlineBeatmapSet/BasicStats.cs

@@ -15,7 +15,20 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
 {
     public class BasicStats : Container
     {
-        private readonly Statistic length, circleCount, sliderCount;
+        private readonly Statistic length, bpm, circleCount, sliderCount;
+
+        private BeatmapSetInfo beatmapSet;
+        public BeatmapSetInfo BeatmapSet
+        {
+            get { return beatmapSet; }
+            set
+            {
+                if (value == beatmapSet) return;
+                beatmapSet = value;
+
+                bpm.Value = BeatmapSet.OnlineInfo.BPM.ToString(@"0.##");
+            }
+        }
 
         private BeatmapInfo beatmap;
         public BeatmapInfo Beatmap
@@ -32,7 +45,7 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
             }
         }
 
-        public BasicStats(BeatmapSetInfo set)
+        public BasicStats()
         {
             Child = new FillFlowContainer
             {
@@ -42,11 +55,7 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
                 Children = new[]
                 {
                     length = new Statistic(FontAwesome.fa_clock_o, "Length") { Width = 0.25f },
-                    new Statistic(FontAwesome.fa_circle, "BPM")
+                    bpm = new Statistic(FontAwesome.fa_circle, "BPM") { Width = 0.25f },
-                    {
-                        Width = 0.25f,
-                        Value = set.OnlineInfo.BPM.ToString(@"0.##"),
-                    },
                     circleCount = new Statistic(FontAwesome.fa_circle_o, "Circle Count") { Width = 0.25f },
                     sliderCount = new Statistic(FontAwesome.fa_circle, "Slider Count") { Width = 0.25f },
                 },

osu.Game/Overlays/OnlineBeatmapSet/BeatmapPicker.cs

@@ -28,10 +28,42 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
 
         private readonly DifficultiesContainer difficulties;
         private readonly OsuSpriteText version, starRating;
+        private readonly Statistic plays, favourites;
 
         public readonly Bindable<BeatmapInfo> Beatmap = new Bindable<BeatmapInfo>();
 
-        public BeatmapPicker(BeatmapSetInfo set)
+        private BeatmapSetInfo beatmapSet;
+        public BeatmapSetInfo BeatmapSet
+        {
+            get { return beatmapSet; }
+            set
+            {
+                if (value == beatmapSet) return;
+                beatmapSet = value;
+
+                Beatmap.Value = BeatmapSet.Beatmaps.First();
+                plays.Value = BeatmapSet.OnlineInfo.PlayCount;
+                favourites.Value = BeatmapSet.OnlineInfo.FavouriteCount;
+                difficulties.ChildrenEnumerable = BeatmapSet.Beatmaps.Select(b => new DifficultySelectorButton(b)
+                {
+                    State = DifficultySelectorState.NotSelected,
+                    OnHovered = beatmap =>
+                    {
+                        showBeatmap(beatmap);
+                        starRating.Text = beatmap.StarDifficulty.ToString("Star Difficulty 0.##");
+                        starRating.FadeIn(100);
+                    },
+                    OnClicked = beatmap =>
+                    {
+                        Beatmap.Value = beatmap;
+                    },
+                });
+
+                updateDifficultyButtons();
+            }
+        }
+
+        public BeatmapPicker()
         {
             RelativeSizeAxes = Axes.X;
             AutoSizeAxes = Axes.Y;
@@ -89,36 +121,19 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
                             Margin = new MarginPadding { Top = 5 },
                             Children = new[]
                             {
-                                new Statistic(FontAwesome.fa_play_circle, set.OnlineInfo.PlayCount),
+                                plays = new Statistic(FontAwesome.fa_play_circle),
-                                new Statistic(FontAwesome.fa_heart, set.OnlineInfo.FavouriteCount),
+                                favourites = new Statistic(FontAwesome.fa_heart),
                             },
                         },
                     },
                 },
             };
 
-            Beatmap.Value = set.Beatmaps.First();
-
             Beatmap.ValueChanged += b =>
             {
                 showBeatmap(b);
                 updateDifficultyButtons();
             };
-
-            difficulties.ChildrenEnumerable = set.Beatmaps.Select(b => new DifficultySelectorButton(b)
-            {
-                State = DifficultySelectorState.NotSelected,
-                OnHovered = beatmap =>
-                {
-                    showBeatmap(beatmap);
-                    starRating.Text = beatmap.StarDifficulty.ToString("Star Difficulty 0.##");
-                    starRating.FadeIn(100);
-                },
-                OnClicked = beatmap =>
-                {
-                    Beatmap.Value = beatmap;
-                },
-            });
         }
 
         [BackgroundDependencyLoader]
@@ -261,7 +276,7 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
                 }
             }
 
-            public Statistic(FontAwesome icon, int value = 0)
+            public Statistic(FontAwesome icon)
             {
                 AutoSizeAxes = Axes.Both;
                 Direction = FillDirection.Horizontal;
@@ -285,8 +300,6 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
                         TextSize = 14,
                     },
                 };
-
-                Value = value;
             }
         }
 

osu.Game/Overlays/OnlineBeatmapSet/Details.cs

@@ -14,10 +14,24 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
 {
     public class Details : FillFlowContainer
     {
+        private readonly PreviewButton preview;
         private readonly BasicStats basic;
         private readonly AdvancedStats advanced;
         private readonly UserRatings ratings;
 
+        private BeatmapSetInfo beatmapSet;
+        public BeatmapSetInfo BeatmapSet
+        {
+            get { return beatmapSet; }
+            set
+            {
+                if (value == beatmapSet) return;
+                beatmapSet = value;
+
+                basic.BeatmapSet = preview.BeatmapSet = BeatmapSet;
+            }
+        }
+
         private BeatmapInfo beatmap;
         public BeatmapInfo Beatmap
         {
@@ -32,7 +46,7 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
             }
         }
 
-        public Details(BeatmapSetInfo set)
+        public Details()
         {
             Width = OnlineBeatmapSetOverlay.RIGHT_WIDTH;
             AutoSizeAxes = Axes.Y;
@@ -40,17 +54,13 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
 
             Children = new Drawable[]
             {
-                new AsyncLoadWrapper(new PreviewButton(set)
+                preview = new PreviewButton
                 {
                     RelativeSizeAxes = Axes.X,
-                })
-                {
-                    RelativeSizeAxes = Axes.X,
-                    AutoSizeAxes = Axes.Y,
                 },
                 new DetailBox
                 {
-                    Child = basic = new BasicStats(set)
+                    Child = basic = new BasicStats()
                     {
                         RelativeSizeAxes = Axes.X,
                         AutoSizeAxes = Axes.Y,

osu.Game/Overlays/OnlineBeatmapSet/Header.cs

@@ -24,10 +24,50 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
         private const float buttons_spacing = 5;
 
         private readonly Box tabsBg;
+        private readonly Container coverContainer;
+        private readonly OsuSpriteText title, artist;
+        private readonly AuthorInfo author;
+        private readonly Details details;
+
+        private DelayedLoadWrapper cover;
 
         public readonly BeatmapPicker Picker;
 
-        public Header(BeatmapSetInfo set)
+        private BeatmapSetInfo beatmapSet;
+        public BeatmapSetInfo BeatmapSet
+        {
+            get { return beatmapSet; }
+            set
+            {
+                if (value == beatmapSet) return;
+                beatmapSet = value;
+
+                Picker.BeatmapSet = author.BeatmapSet = details.BeatmapSet = BeatmapSet;
+                title.Text = BeatmapSet.Metadata.Title;
+                artist.Text = BeatmapSet.Metadata.Artist;
+
+                if (cover != null)
+                    cover.FadeOut(400, Easing.Out);
+
+                coverContainer.Add(cover = new DelayedLoadWrapper(new BeatmapSetCover(BeatmapSet)
+                {
+                    Anchor = Anchor.Centre,
+                    Origin = Anchor.Centre,
+                    RelativeSizeAxes = Axes.Both,
+                    FillMode = FillMode.Fill,
+                    OnLoadComplete = d =>
+                    {
+                        d.FadeInFromZero(400, Easing.Out);
+                    },
+                })
+                {
+                    RelativeSizeAxes = Axes.Both,
+                    TimeBeforeLoad = 300
+                });
+            }
+        }
+
+        public Header()
         {
             RelativeSizeAxes = Axes.X;
             Height = 400;
@@ -42,7 +82,6 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
 
             Container noVideoButtons;
             FillFlowContainer videoButtons;
-            Details details;
             Children = new Drawable[]
             {
                 new Container
@@ -73,20 +112,9 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
                                     RelativeSizeAxes = Axes.Both,
                                     Colour = Color4.Black,
                                 },
-                                new DelayedLoadWrapper(new BeatmapSetCover(set)
+                                coverContainer = new Container
-                                {
-                                    Anchor = Anchor.Centre,
-                                    Origin = Anchor.Centre,
-                                    RelativeSizeAxes = Axes.Both,
-                                    FillMode = FillMode.Fill,
-                                    OnLoadComplete = d =>
-                                    {
-                                        d.FadeInFromZero(400, Easing.Out);
-                                    },
-                                })
                                 {
                                     RelativeSizeAxes = Axes.Both,
-                                    TimeBeforeLoad = 300
                                 },
                                 new Box
                                 {
@@ -109,17 +137,15 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
                                     {
                                         RelativeSizeAxes = Axes.X,
                                         Height = 113,
-                                        Child = Picker = new BeatmapPicker(set),
+                                        Child = Picker = new BeatmapPicker(),
                                     },
-                                    new OsuSpriteText
+                                    title = new OsuSpriteText
                                     {
-                                        Text = set.Metadata.Title,
                                         Font = @"Exo2.0-BoldItalic",
                                         TextSize = 37,
                                     },
-                                    new OsuSpriteText
+                                    artist = new OsuSpriteText
                                     {
-                                        Text = set.Metadata.Artist,
                                         Font = @"Exo2.0-SemiBoldItalic",
                                         TextSize = 25,
                                     },
@@ -128,7 +154,7 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
                                         RelativeSizeAxes = Axes.X,
                                         AutoSizeAxes = Axes.Y,
                                         Margin = new MarginPadding { Top = 20 },
-                                        Child = new AuthorInfo(set.OnlineInfo),
+                                        Child = author = new AuthorInfo(),
                                     },
                                     new Container
                                     {
@@ -168,7 +194,7 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
                                 },
                             },
                         },
-                        details = new Details(set)
+                        details = new Details
                         {
                             Anchor = Anchor.BottomRight,
                             Origin = Anchor.BottomRight,

osu.Game/Overlays/OnlineBeatmapSet/PreviewButton.cs

@@ -19,13 +19,27 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
 {
     public class PreviewButton : OsuClickableContainer
     {
-        private readonly BeatmapSetInfo set;
         private readonly Box bg, progress;
         private readonly SpriteIcon icon;
 
         private AudioManager audio;
         private Track preview;
 
+        private BeatmapSetInfo beatmapSet;
+        public BeatmapSetInfo BeatmapSet
+        {
+            get { return beatmapSet; }
+            set
+            {
+                if (value == beatmapSet) return;
+                beatmapSet = value;
+
+                Playing = false;
+                preview = null;
+                loadPreview();
+            }
+        }
+
         private bool playing;
         public bool Playing
         {
@@ -35,6 +49,8 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
                 if (value == playing) return;
                 playing = value;
 
+                if (progress == null) return;
+
                 if (Playing)
                 {
                     icon.Icon = FontAwesome.fa_stop;
@@ -52,9 +68,8 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
             }
         }
 
-        public PreviewButton(BeatmapSetInfo set)
+        public PreviewButton()
         {
-            this.set = set;
             Height = 42;
 
             Children = new Drawable[]
@@ -95,8 +110,6 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
         {
             this.audio = audio;
             progress.Colour = colours.Yellow;
-
-            loadPreview();
         }
 
         protected override void Update()
@@ -130,9 +143,9 @@ namespace osu.Game.Overlays.OnlineBeatmapSet
 
         private void loadPreview()
         {
-            if (preview?.HasCompleted ?? true)
+            if (preview == null || (preview?.HasCompleted ?? true) && BeatmapSet != null)
             {
-                preview = audio.Track.Get(set.OnlineInfo.Preview);
+                preview = audio.Track.Get(BeatmapSet.OnlineInfo.Preview);
                 preview.Volume.Value = 0.5;
             }
             else

osu.Game/Overlays/OnlineBeatmapSetOverlay.cs

@@ -1,7 +1,6 @@
 // Copyright (c) 2007-2017 ppy Pty Ltd <contact@ppy.sh>.
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
-using System.Linq;
 using OpenTK;
 using OpenTK.Graphics;
 using osu.Framework.Extensions.Color4Extensions;
@@ -62,14 +61,14 @@ namespace osu.Game.Overlays
                         Direction = FillDirection.Vertical,
                         Children = new Drawable[]
                         {
-                            // header = new Header(),
+                            header = new Header(),
                             info = new Info(),
                         },
                     },
                 },
             };
 
-            // header.Picker.Beatmap.ValueChanged += b => info.Beatmap = b;
+            header.Picker.Beatmap.ValueChanged += b => info.Beatmap = b;
         }
 
         protected override void PopIn()
@@ -86,8 +85,7 @@ namespace osu.Game.Overlays
 
         public void ShowBeatmapSet(BeatmapSetInfo set)
         {
-            /*header.BeatmapSet = */info.BeatmapSet = set;
+            header.BeatmapSet = info.BeatmapSet = set;
-            info.Beatmap = set.Beatmaps.Last();
 
             Show();
         }