Only fetch lyrics when the lyrics tab is visible

src/CMakeLists.txt

@@ -89,6 +89,7 @@ set(SOURCES
   lyrics/lyricprovider.cpp
   lyrics/lyricsettings.cpp
   lyrics/lyricview.cpp
+  lyrics/songinfobase.cpp
   lyrics/ultimatelyricsreader.cpp
 
   playlist/playlist.cpp
@@ -224,6 +225,7 @@ set(HEADERS
   lyrics/lyricprovider.h
   lyrics/lyricsettings.h
   lyrics/lyricview.h
+  lyrics/songinfobase.h
   lyrics/ultimatelyricsreader.h
 
   playlist/playlist.h

src/lyrics/lyricview.cpp

@@ -19,7 +19,7 @@
 #include "ui_lyricview.h"
 
 LyricView::LyricView(QWidget *parent)
-  : QWidget(parent),
+  : SongInfoBase(parent),
     ui_(new Ui_LyricView),
     fetcher_(NULL),
     current_request_id_(-1)
@@ -40,7 +40,7 @@ void LyricView::set_network(NetworkAccessManager* network) {
           SLOT(SearchProgress(int,QString)));
 }
 
-void LyricView::SongChanged(const Song& metadata) {
+void LyricView::Update(const Song& metadata) {
   current_request_id_ = fetcher_->SearchAsync(metadata);
 
   ui_->busy_text->SetText(tr("Searching..."));

src/lyrics/lyricview.h

@@ -17,15 +17,14 @@
 #ifndef LYRICVIEW_H
 #define LYRICVIEW_H
 
+#include "songinfobase.h"
 #include "core/song.h"
 
-#include <QWidget>
-
 class LyricFetcher;
 class NetworkAccessManager;
 class Ui_LyricView;
 
-class LyricView : public QWidget {
+class LyricView : public SongInfoBase {
   Q_OBJECT
 
 public:
@@ -35,8 +34,8 @@ public:
   void set_network(NetworkAccessManager* network);
   LyricFetcher* fetcher() const { return fetcher_; }
 
-public slots:
-  void SongChanged(const Song& metadata);
+protected:
+  void Update(const Song& metadata);
 
 private slots:
   void SearchProgress(int id, const QString& provider);

src/lyrics/songinfobase.cpp

@@ -0,0 +1,45 @@
+/* This file is part of Clementine.
+
+   Clementine is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   Clementine is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Clementine.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "songinfobase.h"
+
+SongInfoBase::SongInfoBase(QWidget* parent)
+  : QWidget(parent),
+    dirty_(false)
+{
+}
+
+void SongInfoBase::SongChanged(const Song& metadata) {
+  if (isVisible()) {
+    Update(metadata);
+    dirty_ = false;
+  } else {
+    queued_metadata_ = metadata;
+    dirty_ = true;
+  }
+}
+
+void SongInfoBase::SongFinished() {
+  dirty_ = false;
+}
+
+void SongInfoBase::showEvent(QShowEvent* e) {
+  if (dirty_) {
+    Update(queued_metadata_);
+    dirty_ = false;
+  }
+  QWidget::showEvent(e);
+}

src/lyrics/songinfobase.h

@@ -0,0 +1,44 @@
+/* This file is part of Clementine.
+
+   Clementine is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   Clementine is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Clementine.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef SONGINFOBASE_H
+#define SONGINFOBASE_H
+
+#include <QWidget>
+
+#include "core/song.h"
+
+class SongInfoBase : public QWidget {
+  Q_OBJECT
+
+public:
+  SongInfoBase(QWidget* parent = 0);
+
+public slots:
+  void SongChanged(const Song& metadata);
+  void SongFinished();
+
+protected:
+  void showEvent(QShowEvent* e);
+
+  virtual void Update(const Song& metadata) {}
+
+private:
+  Song queued_metadata_;
+  bool dirty_;
+};
+
+#endif // SONGINFOBASE_H

src/ui/mainwindow.cpp

@@ -351,7 +351,6 @@ MainWindow::MainWindow(NetworkAccessManager* network, Engine::Type engine, QWidg
   connect(player_, SIGNAL(ForceShowOSD(Song)), SLOT(ForceShowOSD(Song)));
   connect(playlists_, SIGNAL(CurrentSongChanged(Song)), osd_, SLOT(SongChanged(Song)));
   connect(playlists_, SIGNAL(CurrentSongChanged(Song)), player_, SLOT(CurrentMetadataChanged(Song)));
-  connect(playlists_, SIGNAL(CurrentSongChanged(Song)), lyric_view_, SLOT(SongChanged(Song)));
   connect(playlists_, SIGNAL(PlaylistChanged()), player_, SLOT(PlaylistChanged()));
   connect(playlists_, SIGNAL(EditingFinished(QModelIndex)), SLOT(PlaylistEditFinished(QModelIndex)));
   connect(playlists_, SIGNAL(Error(QString)), SLOT(ShowErrorDialog(QString)));
@@ -491,6 +490,7 @@ MainWindow::MainWindow(NetworkAccessManager* network, Engine::Type engine, QWidg
 
   // Lyrics
   lyric_view_->set_network(network);
+  ConnectInfoView(lyric_view_);
 
   // Analyzer
   ui_->analyzer->SetEngine(player_->GetEngine());
@@ -1582,3 +1582,9 @@ void MainWindow::ShowVisualisations() {
 void MainWindow::AddFancyTab(QWidget* widget, const QIcon& icon, const QString& label) {
   ui_->tabs->addTab(widget, icon, label);
 }
+
+void MainWindow::ConnectInfoView(SongInfoBase* view) {
+  connect(playlists_, SIGNAL(CurrentSongChanged(Song)), view, SLOT(SongChanged(Song)));
+  connect(player_, SIGNAL(PlaylistFinished()), view, SLOT(SongFinished()));
+  connect(player_, SIGNAL(Stopped()), view, SLOT(SongFinished()));
+}

src/ui/mainwindow.h

@@ -59,6 +59,7 @@ class RadioItem;
 class RadioModel;
 class RadioViewContainer;
 class Song;
+class SongInfoBase;
 class SystemTrayIcon;
 class TaskManager;
 class TranscodeDialog;
@@ -196,6 +197,7 @@ class MainWindow : public QMainWindow, public PlatformInterface {
   void AddDeviceSongsToPlaylist(bool clear_first, const SongList& songs);
   void AddUrls(bool play_now, const QList<QUrl>& urls);
   void AddFancyTab(QWidget* widget, const QIcon& icon, const QString& label);
+  void ConnectInfoView(SongInfoBase* view);
 
  private:
   Ui_MainWindow* ui_;