[banshee] Keep the playing song visible in the track list

[Gabriel Burt <gburt src gnome org>]

commit db62ad34cc928e932a77c0bb9773a04e4be0c229
Author: Alexander Kojevnikov <alexander kojevnikov com>
Date:   Wed Jul 1 11:07:00 2009 -0500

    Keep the playing song visible in the track list
    
    Signed-off-by: Gabriel Burt <gabriel burt gmail com>

 .../Banshee.Collection.Gui/BaseTrackListView.cs    |   60 +++++++++++++++++++-
 .../Banshee.Collection.Gui/TrackFilterListView.cs  |    6 ++
 .../ListView/ListView_Interaction.cs               |   26 ++++++++-
 .../Hyena.Data.Gui/ListView/ListView_Model.cs      |   13 ----
 .../Hyena.Data.Gui/ListView/ListView_Windowing.cs  |    2 +-
 5 files changed, 89 insertions(+), 18 deletions(-)
---
diff --git a/src/Core/Banshee.ThickClient/Banshee.Collection.Gui/BaseTrackListView.cs b/src/Core/Banshee.ThickClient/Banshee.Collection.Gui/BaseTrackListView.cs
index 50b5690..0d21bc4 100644
--- a/src/Core/Banshee.ThickClient/Banshee.Collection.Gui/BaseTrackListView.cs
+++ b/src/Core/Banshee.ThickClient/Banshee.Collection.Gui/BaseTrackListView.cs
@@ -34,6 +34,7 @@ using Hyena.Data;
 using Hyena.Data.Gui;
 using Hyena.Gui;
 
+using Banshee.Collection.Database;
 using Banshee.Sources;
 using Banshee.ServiceStack;
 using Banshee.MediaEngine;
@@ -51,7 +52,8 @@ namespace Banshee.Collection.Gui
             RowSensitivePropertyName = "CanPlay";
             RowBoldPropertyName = "IsPlaying";
             
-            ServiceManager.PlayerEngine.ConnectEvent (OnPlayerEvent, PlayerEvent.StateChange);
+            ServiceManager.PlayerEngine.ConnectEvent (
+                OnPlayerEvent, PlayerEvent.StartOfStream | PlayerEvent.StateChange);
             
             ForceDragSourceSet = true;
             IsEverReorderable = true;
@@ -88,10 +90,62 @@ namespace Banshee.Collection.Gui
             ServiceManager.Get<InterfaceActionService> ().TrackActions["TrackContextMenuAction"].Activate ();
             return true;
         }
-        
+
+        private string user_query;
+        protected override void OnModelReloaded ()
+        {
+            base.OnModelReloaded ();
+
+            var model = Model as IFilterable;
+            if (model != null && user_query != model.UserQuery) {
+                // Make sure selected tracks are visible as the user edits the query.
+                CenterOnSelection ();
+                user_query = model.UserQuery;
+            }
+        }
+
         private void OnPlayerEvent (PlayerEventArgs args)
         {
-            QueueDraw ();
+            if (args.Event == PlayerEvent.StartOfStream) {
+                UpdateSelection ();
+            } else if (args.Event == PlayerEvent.StateChange) {
+                QueueDraw ();
+            }
+        }
+
+        private TrackInfo current_track;
+        private void UpdateSelection ()
+        {
+            TrackInfo old_track = current_track;
+            current_track = ServiceManager.PlayerEngine.CurrentTrack;
+
+            var track_model = Model as TrackListModel;
+            if (track_model == null) {
+                return;
+            }
+
+            if (Selection.Count > 1) {
+                return;
+            }
+
+            int old_index = Selection.FirstIndex;
+            TrackInfo selected_track = Selection.Count == 1 ? track_model[old_index] : null;
+            if (selected_track != null && !selected_track.TrackEqual (old_track)) {
+                return;
+            }
+
+            int current_index = track_model.IndexOf (current_track);
+            if (current_index == -1) {
+                return;
+            }
+
+            Selection.Clear (false);
+            Selection.QuietSelect (current_index);
+            Selection.FocusedIndex = current_index;
+
+            if (old_index == -1 || IsRowVisible (old_index)) {
+                CenterOn (current_index);
+            }
         }
 
 #region Drag and Drop
diff --git a/src/Core/Banshee.ThickClient/Banshee.Collection.Gui/TrackFilterListView.cs b/src/Core/Banshee.ThickClient/Banshee.Collection.Gui/TrackFilterListView.cs
index 67b347b..259188d 100644
--- a/src/Core/Banshee.ThickClient/Banshee.Collection.Gui/TrackFilterListView.cs
+++ b/src/Core/Banshee.ThickClient/Banshee.Collection.Gui/TrackFilterListView.cs
@@ -52,6 +52,12 @@ namespace Banshee.Collection.Gui
             RowActivated += OnRowActivated;
         }
 
+        protected override void OnModelReloaded ()
+        {
+            base.OnModelReloaded ();
+            CenterOnSelection ();
+        }
+
         protected virtual void OnRowActivated (object o, EventArgs args)
         {
             ServiceManager.PlaybackController.NextSource = (ServiceManager.SourceManager.ActiveSource as Banshee.Sources.ITrackModelSource);
diff --git a/src/Libraries/Hyena.Gui/Hyena.Data.Gui/ListView/ListView_Interaction.cs b/src/Libraries/Hyena.Gui/Hyena.Data.Gui/ListView/ListView_Interaction.cs
index d744725..1b44fee 100644
--- a/src/Libraries/Hyena.Gui/Hyena.Data.Gui/ListView/ListView_Interaction.cs
+++ b/src/Libraries/Hyena.Gui/Hyena.Data.Gui/ListView/ListView_Interaction.cs
@@ -784,7 +784,31 @@ namespace Hyena.Data.Gui
         {
             ScrollTo (index - RowsInView/2 + 1);
         }
-                
+
+        public bool IsRowVisible (int index)
+        {
+            double y = GetYAtRow (index);
+            return vadjustment.Value <= y && y < vadjustment.Value + vadjustment.PageSize;
+        }
+
+        protected void CenterOnSelection ()
+        {
+            if (Selection != null && Selection.Count > 0 && !Selection.AllSelected) {
+                bool selection_in_view = false;
+                int first_row = GetRowAtY (0);
+                for (int i = 0; i < RowsInView; i++) {
+                    if (Selection.Contains (first_row + i)) {
+                        selection_in_view = true;
+                        break;
+                    }
+                }
+
+                if (!selection_in_view) {
+                    CenterOn (Selection.Ranges[0].Start);
+                }
+            }
+        }
+
         protected override void OnSetScrollAdjustments (Adjustment hadj, Adjustment vadj)
         {
             if (hadj == null || vadj == null) {
diff --git a/src/Libraries/Hyena.Gui/Hyena.Data.Gui/ListView/ListView_Model.cs b/src/Libraries/Hyena.Gui/Hyena.Data.Gui/ListView/ListView_Model.cs
index b28793d..e9fe295 100644
--- a/src/Libraries/Hyena.Gui/Hyena.Data.Gui/ListView/ListView_Model.cs
+++ b/src/Libraries/Hyena.Gui/Hyena.Data.Gui/ListView/ListView_Model.cs
@@ -88,19 +88,6 @@ namespace Hyena.Data.Gui
             } else if (Model.Count <= RowsInView) {
                 // If our view fits all rows at once, make sure we're scrolled to the top
                 ScrollTo (0.0);
-            } else if (Selection != null && Selection.Count > 0 && !Selection.AllSelected) {
-                bool selection_in_view = false;
-                int first_row = GetRowAtY (0);
-                for (int i = 0; i < RowsInView; i++) {
-                    if (Selection.Contains (first_row + i)) {
-                        selection_in_view = true;
-                        break;
-                    }
-                }
-
-                if (!selection_in_view) {
-                    CenterOn (Selection.Ranges[0].Start);
-                }
             } else if (vadjustment != null) {
                 ScrollTo (vadjustment.Value);
             }
diff --git a/src/Libraries/Hyena.Gui/Hyena.Data.Gui/ListView/ListView_Windowing.cs b/src/Libraries/Hyena.Gui/Hyena.Data.Gui/ListView/ListView_Windowing.cs
index e647abf..c9b3c0b 100644
--- a/src/Libraries/Hyena.Gui/Hyena.Data.Gui/ListView/ListView_Windowing.cs
+++ b/src/Libraries/Hyena.Gui/Hyena.Data.Gui/ListView/ListView_Windowing.cs
@@ -175,7 +175,7 @@ namespace Hyena.Data.Gui
             InvalidateList ();
         }
         
-        private int RowsInView {
+        protected int RowsInView {
             get { return (int) Math.Ceiling ((list_rendering_alloc.Height + RowHeight) / (double) RowHeight); }
         }
     }