Remember the selected playlist items when switching between playlist tabs. Fixes issue #758

src/playlist/playlistcontainer.cpp

@@ -158,6 +158,7 @@ void PlaylistContainer::SetViewModel(Playlist* playlist) {
   view()->setModel(playlist->proxy());
   view()->SetItemDelegates(manager_->library_backend());
   view()->SetPlaylist(playlist);
+  view()->selectionModel()->select(manager_->current_selection(), QItemSelectionModel::ClearAndSelect);
   playlist->IgnoreSorting(false);
 
   connect(view()->selectionModel(), SIGNAL(selectionChanged(QItemSelection,QItemSelection)),

src/playlist/playlistmanager.cpp

@@ -223,7 +223,7 @@ void PlaylistManager::UpdateSummaryText() {
   int selected = 0;
 
   // Get the length of the selected tracks
-  foreach (const QItemSelectionRange& range, current_selection_) {
+  foreach (const QItemSelectionRange& range, playlists_[current_id()].selection) {
     if (!range.isValid())
       continue;
 
@@ -251,8 +251,8 @@ void PlaylistManager::UpdateSummaryText() {
   emit SummaryTextChanged(summary);
 }
 
-void PlaylistManager::SelectionChanged(const QItemSelection &selection) {
-  current_selection_ = selection;
+void PlaylistManager::SelectionChanged(const QItemSelection& selection) {
+  playlists_[current_id()].selection = selection;
   UpdateSummaryText();
 }
 

src/playlist/playlistmanager.h

@@ -47,6 +47,10 @@ public:
   Playlist* current() const { return playlist(current_id()); }
   Playlist* active() const { return playlist(active_id()); }
 
+  const QItemSelection& selection(int id) const { return playlists_[id].selection; }
+  const QItemSelection& current_selection() const { return selection(current_id()); }
+  const QItemSelection& active_selection() const { return selection(active_id()); }
+
   QString name(int index) const { return playlists_[index].name; }
 
   void Init(LibraryBackend* library_backend, PlaylistBackend* playlist_backend,
@@ -109,6 +113,7 @@ private:
     Data(Playlist* _p = NULL, const QString& _name = QString()) : p(_p), name(_name) {}
     Playlist* p;
     QString name;
+    QItemSelection selection;
   };
 
   TaskManager* task_manager_;
@@ -117,8 +122,6 @@ private:
   PlaylistSequence* sequence_;
   PlaylistParser* parser_;
 
-  QItemSelection current_selection_;
-
   // key = id
   QMap<int, Data> playlists_;