Do gnome global shortcut registration in a background thread

src/CMakeLists.txt

@@ -247,6 +247,7 @@ set(HEADERS
   core/database.h
   core/deletefiles.h
   core/globalshortcuts.h
+  core/globalshortcutbackend.h
   core/gnomeglobalshortcutbackend.h
   core/kittenloader.h
   core/mergedproxymodel.h

src/core/globalshortcutbackend.cpp

@@ -18,26 +18,63 @@
 #include "globalshortcutbackend.h"
 #include "globalshortcuts.h"
 
+#include <QFuture>
+#include <QFutureWatcher>
+#include <QtConcurrentRun>
+
 GlobalShortcutBackend::GlobalShortcutBackend(GlobalShortcuts *parent)
   : QObject(parent),
     manager_(parent),
-    active_(false)
+    active_(false),
+    register_in_progress_(false),
+    should_unregister_(false)
 {
 }
 
-bool GlobalShortcutBackend::Register() {
-  bool ret = DoRegister();
-  if (ret)
-    active_ = true;
-  return ret;
+void GlobalShortcutBackend::Register() {
+  if (register_in_progress_) {
+    should_unregister_ = false;
+    return;
+  }
+
+  if (RegisterInNewThread()) {
+    register_in_progress_ = true;
+    QFuture<bool> future = QtConcurrent::run(this, &GlobalShortcutBackend::DoRegister);
+
+    QFutureWatcher<bool>* watcher = new QFutureWatcher<bool>(this);
+    watcher->setFuture(future);
+    connect(watcher, SIGNAL(finished()), SLOT(RegisterFinishedSlot()));
+  } else {
+    bool ret = DoRegister();
+    if (ret)
+      active_ = true;
+    emit RegisterFinished(ret);
+  }
 }
 
 void GlobalShortcutBackend::Unregister() {
+  if (register_in_progress_) {
+    should_unregister_ = true;
+    return;
+  }
+
   DoUnregister();
   active_ = false;
 }
 
-void GlobalShortcutBackend::Reregister() {
-  Unregister();
-  Register();
+void GlobalShortcutBackend::RegisterFinishedSlot() {
+  QFutureWatcher<bool>* watcher = dynamic_cast<QFutureWatcher<bool>*>(sender());
+  const bool success = watcher->result();
+  watcher->deleteLater();
+
+  register_in_progress_ = false;
+  if (success)
+    active_ = true;
+
+  if (should_unregister_) {
+    Unregister();
+    should_unregister_ = false;
+  } else {
+    emit RegisterFinished(success);
+  }
 }

src/core/globalshortcutbackend.h

@@ -23,22 +23,34 @@
 class GlobalShortcuts;
 
 class GlobalShortcutBackend : public QObject {
+  Q_OBJECT
+
 public:
   GlobalShortcutBackend(GlobalShortcuts* parent = 0);
   virtual ~GlobalShortcutBackend() {}
 
   bool is_active() const { return active_; }
 
-  bool Register();
+  void Register();
   void Unregister();
-  void Reregister();
+
+signals:
+  void RegisterFinished(bool success);
 
 protected:
+  virtual bool RegisterInNewThread() const { return false; }
   virtual bool DoRegister() = 0;
   virtual void DoUnregister() = 0;
 
   GlobalShortcuts* manager_;
   bool active_;
+
+private slots:
+  void RegisterFinishedSlot();
+
+private:
+  bool register_in_progress_;
+  bool should_unregister_;
 };
 
 #endif // GLOBALSHORTCUTBACKEND_H

src/core/globalshortcuts.cpp

@@ -67,8 +67,7 @@ GlobalShortcuts::GlobalShortcuts(QObject *parent)
   connect(rating_signals_mapper_, SIGNAL(mapped(int)), SIGNAL(RateCurrentSong(int)));
 
   // Create backends - these do the actual shortcut registration
-  if (IsGsdAvailable())
-    gnome_backend_ = new GnomeGlobalShortcutBackend(this);
+  gnome_backend_ = new GnomeGlobalShortcutBackend(this);
 
 #ifndef Q_OS_DARWIN
   system_backend_ = new QxtGlobalShortcutBackend(this);
@@ -76,6 +75,9 @@ GlobalShortcuts::GlobalShortcuts(QObject *parent)
   system_backend_ = new MacGlobalShortcutBackend(this);
 #endif
 
+  connect(gnome_backend_, SIGNAL(RegisterFinished(bool)), SLOT(RegisterFinished(bool)));
+  connect(system_backend_, SIGNAL(RegisterFinished(bool)), SLOT(RegisterFinished(bool)));
+
   ReloadSettings();
 }
 
@@ -127,19 +129,27 @@ void GlobalShortcuts::ReloadSettings() {
 }
 
 void GlobalShortcuts::Unregister() {
-  if (gnome_backend_ && gnome_backend_->is_active())
+  if (gnome_backend_->is_active())
     gnome_backend_->Unregister();
-  if (system_backend_ && system_backend_->is_active())
+  if (system_backend_->is_active())
     system_backend_->Unregister();
 }
 
 void GlobalShortcuts::Register() {
-  if (gnome_backend_ && use_gnome_)
+  if (use_gnome_)
     gnome_backend_->Register();
-  else if (system_backend_)
+  else
     system_backend_->Register();
 }
 
+void GlobalShortcuts::RegisterFinished(bool success) {
+  GlobalShortcutBackend* backend = qobject_cast<GlobalShortcutBackend*>(sender());
+
+  if (backend == gnome_backend_ && !success) {
+    system_backend_->Register();
+  }
+}
+
 bool GlobalShortcuts::IsMacAccessibilityEnabled() const {
 #ifdef Q_OS_MAC
   return static_cast<MacGlobalShortcutBackend*>(system_backend_)->IsAccessibilityEnabled();

src/core/globalshortcuts.h

@@ -77,6 +77,9 @@ private:
                          int rating, const QKeySequence& default_key = QKeySequence(0));
   Shortcut AddShortcut(const QString& id, const QString& name, const QKeySequence& default_key);
 
+private slots:
+  void RegisterFinished(bool success);
+
 private:
   GlobalShortcutBackend* gnome_backend_;
   GlobalShortcutBackend* system_backend_;

src/core/gnomeglobalshortcutbackend.cpp

@@ -36,22 +36,29 @@ GnomeGlobalShortcutBackend::GnomeGlobalShortcutBackend(GlobalShortcuts* parent)
 }
 
 bool GnomeGlobalShortcutBackend::DoRegister() {
-  qDebug() << __PRETTY_FUNCTION__;
 #ifdef QT_DBUS_LIB
+  qDebug() << __PRETTY_FUNCTION__ << "- starting";
   // Check if the GSD service is available
-  if (!QDBusConnection::sessionBus().interface()->isServiceRegistered(kGsdService))
+  if (!QDBusConnection::sessionBus().interface()->isServiceRegistered(kGsdService)) {
+    qDebug() << __PRETTY_FUNCTION__ << "- gnome settings daemon not registered";
     return false;
+  }
 
   if (!interface_) {
     interface_ = new QDBusInterface(
-        kGsdService, kGsdPath, kGsdInterface, QDBusConnection::sessionBus(), this);
+        kGsdService, kGsdPath, kGsdInterface, QDBusConnection::sessionBus());
+    interface_->moveToThread(thread());
+    interface_->setParent(this);
   }
 
   connect(interface_, SIGNAL(MediaPlayerKeyPressed(QString,QString)),
           this, SLOT(GnomeMediaKeyPressed(QString,QString)));
 
+  qDebug() << __PRETTY_FUNCTION__ << "- complete";
+
   return true;
 #else // QT_DBUS_LIB
+  qDebug() << __PRETTY_FUNCTION__ << "- dbus not available";
   return false;
 #endif
 }

src/core/gnomeglobalshortcutbackend.h

@@ -33,6 +33,7 @@ public:
   static const char* kGsdInterface;
 
 protected:
+  bool RegisterInNewThread() const { return true; }
   bool DoRegister();
   void DoUnregister();