Fix fullscreen mode

In some setups, the FullScreen action would get out of sync with
the actual window state and thus kick Quassel into an endless loop
and finally a crash when toggling full screen mode.

Turns out reading the docs for KToggleFullScreenAction helped doing
this properly (avoiding this and other bugs when using QWidget's methods).

Thanks to yofel and hays for reporting, and apachelogger for putting
me on the right track for fixing this.

Fixes #1153, fixes #1258.

diff --git a/src/qtui/mainwin.cpp b/src/qtui/mainwin.cpp
index 9019e24..d5e9b0c 100644 (file)
--- a/src/qtui/mainwin.cpp
+++ b/src/qtui/mainwin.cpp
@@ -385,13 +385,13 @@ void MainWin::setupActions()
             0, 0))->setCheckable(true);
 
 #ifdef HAVE_KDE
-    QAction *fullScreenAct = KStandardAction::fullScreen(this, SLOT(toggleFullscreen()), this, coll);
+    QAction *fullScreenAct = KStandardAction::fullScreen(this, SLOT(onFullScreenToggled()), this, coll);
 #else
     QAction *fullScreenAct = new Action(SmallIcon("view-fullscreen"), tr("&Full Screen Mode"), coll,
-        this, SLOT(toggleFullscreen()), QKeySequence(Qt::Key_F11));
+        this, SLOT(onFullScreenToggled()), QKeySequence(Qt::Key_F11));
     fullScreenAct->setCheckable(true);
 #endif
-    coll->addAction("ToggleFullscreen", fullScreenAct);
+    coll->addAction("ToggleFullScreen", fullScreenAct);
 
     // Settings
     QAction *configureShortcutsAct = new Action(SmallIcon("configure-shortcuts"), tr("Configure &Shortcuts..."), coll,
@@ -920,7 +920,7 @@ void MainWin::setupTopicWidget()
 void MainWin::setupViewMenuTail()
 {
     _viewMenu->addSeparator();
-    _viewMenu->addAction(QtUi::actionCollection("General")->action("ToggleFullscreen"));
+    _viewMenu->addAction(QtUi::actionCollection("General")->action("ToggleFullScreen"));
 }
 
 
@@ -1358,12 +1358,24 @@ void MainWin::showShortcutsDlg()
 }
 
 
-void MainWin::toggleFullscreen()
+void MainWin::onFullScreenToggled()
 {
-    if (isFullScreen())
-        showNormal();
+    // Relying on QWidget::isFullScreen is discouraged, see the KToggleFullScreenAction docs
+    // Also, one should not use showFullScreen() or showNormal(), as those reset all other window flags
+
+    QAction *action = QtUi::actionCollection("General")->action("ToggleFullScreen");
+    if (!action)
+        return;
+
+#ifdef HAVE_KDE
+    KToggleFullScreenAction *kAct = static_cast<KToggleFullScreenAction *>(action);
+    kAct->setFullScreen(this, kAct->isChecked());
+#else
+    if (action->isChecked())
+        setWindowState(windowState() | Qt::WindowFullScreen);
     else
-        showFullScreen();
+        setWindowState(windowState() & ~Qt::WindowFullScreen);
+#endif
 }
 
 

diff --git a/src/qtui/mainwin.h b/src/qtui/mainwin.h
index 9104654..9ae9a2a 100644 (file)
--- a/src/qtui/mainwin.h
+++ b/src/qtui/mainwin.h
@@ -122,7 +122,7 @@ private slots:
     void showNotificationsDlg();
     void showIgnoreList(QString newRule = QString());
     void showShortcutsDlg();
-    void toggleFullscreen();
+    void onFullScreenToggled();
 
     void handleCoreConnectionError(const QString &errorMsg);
     void userAuthenticationRequired(CoreAccount *, bool *valid, const QString &errorMessage);