Gui: Reuse QActions for workbench activation

This fixes segfault that can occour due to keeping reference to QAction
that is supposed to change workbench.

src/Gui/Action.cpp

@@ -627,6 +627,14 @@ WorkbenchGroup::WorkbenchGroup (  Command* pcCmd, QObject * parent )
         this, &WorkbenchGroup::onWorkbenchActivated);
 }
 
+QAction* WorkbenchGroup::getOrCreateAction(const QString& wbName) {
+    if (!actionByWorkbenchName.contains(wbName)) {
+        actionByWorkbenchName[wbName] = new QAction;
+    }
+
+    return actionByWorkbenchName[wbName];
+}
+
 void WorkbenchGroup::addTo(QWidget *widget)
 {
     if (widget->inherits("QToolBar")) {
@@ -657,13 +665,13 @@ void WorkbenchGroup::addTo(QWidget *widget)
 
 void WorkbenchGroup::refreshWorkbenchList()
 {
-    QStringList enabled_wbs_list = DlgSettingsWorkbenchesImp::getEnabledWorkbenches();
+    QStringList enabledWbNames = DlgSettingsWorkbenchesImp::getEnabledWorkbenches();
 
     // Clear the actions.
     for (QAction* action : actions()) {
         groupAction()->removeAction(action);
-        delete action;
     }
+
     enabledWbsActions.clear();
     disabledWbsActions.clear();
 
@@ -671,12 +679,16 @@ void WorkbenchGroup::refreshWorkbenchList()
 
     // Create action list of enabled wb
     int index = 0;
-    for (const auto& wbName : enabled_wbs_list) {
+    for (const auto& wbName : enabledWbNames) {
         QString name = Application::Instance->workbenchMenuText(wbName);
         QPixmap px = Application::Instance->workbenchIcon(wbName);
         QString tip = Application::Instance->workbenchToolTip(wbName);
 
-        QAction* action = groupAction()->addAction(name);
+        QAction* action = getOrCreateAction(wbName);
+        
+        groupAction()->addAction(action);
+
+        action->setText(name);
         action->setCheckable(true);
         action->setData(QVariant(index)); // set the index
         action->setObjectName(wbName);
@@ -694,13 +706,17 @@ void WorkbenchGroup::refreshWorkbenchList()
     }
 
     // Also create action list of disabled wbs
-    QStringList disabled_wbs_list = DlgSettingsWorkbenchesImp::getDisabledWorkbenches();
-    for (const auto& wbName : disabled_wbs_list) {
+    QStringList disabledWbNames = DlgSettingsWorkbenchesImp::getDisabledWorkbenches();
+    for (const auto& wbName : disabledWbNames) {
         QString name = Application::Instance->workbenchMenuText(wbName);
         QPixmap px = Application::Instance->workbenchIcon(wbName);
         QString tip = Application::Instance->workbenchToolTip(wbName);
 
-        QAction* action = groupAction()->addAction(name);
+        QAction* action = getOrCreateAction(wbName);
+
+        groupAction()->addAction(action);
+
+        action->setText(name);
         action->setCheckable(true);
         action->setData(QVariant(index)); // set the index
         action->setObjectName(wbName);

src/Gui/Action.h

@@ -28,6 +28,7 @@
 #include <QAction>
 #include <QComboBox>
 #include <QKeySequence>
+#include <QMap>
 #include <FCGlobal.h>
 
 namespace Gui
@@ -188,13 +189,16 @@ class GuiExport WorkbenchGroup : public ActionGroup
 {
     Q_OBJECT
 
+    QAction* getOrCreateAction(const QString& wbName);
+
 public:
     /**
      * Creates an action for the command \a pcCmd to load the workbench \a name
      * when it gets activated.
      */
-    WorkbenchGroup (Command* pcCmd, QObject * parent);
-    void addTo (QWidget * widget) override;
+    WorkbenchGroup(Command* pcCmd, QObject* parent);
+
+    void addTo(QWidget * widget) override;
     void refreshWorkbenchList();
 
     void slotActivateWorkbench(const char*);
@@ -212,6 +216,8 @@ private:
     QList<QAction*> enabledWbsActions;
     QList<QAction*> disabledWbsActions;
 
+    QMap<QString, QAction*> actionByWorkbenchName;
+
     Q_DISABLE_COPY(WorkbenchGroup)
 };