From 7abdd849dce3734fe11bb95ebcd60a6491b77644 Mon Sep 17 00:00:00 2001
From: stv <stv@opencascade.com>
Date: Fri, 18 Nov 2011 10:08:51 +0000
Subject: [PATCH] Activation of signal "moduleActivated()" performs via custom
 event in ModuleAction. This allow to perform safe ModuleAction combobox
 deletion (not in slot connected to activation signal of combobox). This
 deletion occurs during changing active module if module use
 QApplication::processEvents() (force threat DeferredDelete event) in
 activation/deactivation procedures.

---
 src/LightApp/LightApp_ModuleAction.cxx | 38 ++++++++++++++++++++++++--
 src/LightApp/LightApp_ModuleAction.h   | 11 +++++---
 2 files changed, 43 insertions(+), 6 deletions(-)

diff --git a/src/LightApp/LightApp_ModuleAction.cxx b/src/LightApp/LightApp_ModuleAction.cxx
index 584496a58..14b633dcc 100755
--- a/src/LightApp/LightApp_ModuleAction.cxx
+++ b/src/LightApp/LightApp_ModuleAction.cxx
@@ -24,7 +24,11 @@
 
 #include <QtxComboBox.h>
 #include <QtxActionSet.h>
-#include <QVBoxLayout>
+
+#include <QtGui/QLayout>
+#include <QtGui/QApplication>
+
+#include <QtCore/QEvent>
 
 /*!
   \class LightApp_ModuleAction::ActionSet
@@ -181,6 +185,23 @@ QWidget* LightApp_ModuleAction::ComboAction::createWidget( QWidget* parent )
   \param item identifier
 */
 
+/*!
+  \class LightApp_ModuleAction::ActivateEvent
+  \brief Internal class to represent custom event for transfer the activation item id.
+  \internal
+*/
+class LightApp_ModuleAction::ActivateEvent : public QEvent
+{
+public:
+  ActivateEvent( QEvent::Type type, int id ) : QEvent( type ), myId( id ) {};
+  ~ActivateEvent() {};
+
+  int     id() const { return myId; }
+
+private:
+  int     myId;
+};
+
 /*!
   \class LightApp_ModuleAction
   \brief An action, representing the list of modules to be inserted to the
@@ -413,6 +434,19 @@ void LightApp_ModuleAction::removedFrom( QWidget* w )
   w->removeAction( mySet );
 }
 
+/*!
+  \brief Perform delayed activation with specified id.
+  \param e custom event
+  \return \c true if the event was processed successfully and \c false otherwise.
+*/
+bool LightApp_ModuleAction::event( QEvent* e )
+{
+  if ( e->type() == QEvent::MaxUser )
+    activate( ((ActivateEvent*)e)->id(), false );
+  else
+    return QtxAction::event( e );
+}
+
 /*!
   \fn void LightApp_ModuleAction::moduleActivated( const QString& name );
   \brief Emitted when the module is activated
@@ -568,5 +602,5 @@ void LightApp_ModuleAction::onChanged()
 */
 void LightApp_ModuleAction::onComboActivated( int id )
 {
-  activate( id, false );
+  QApplication::postEvent( this, new ActivateEvent( QEvent::MaxUser, id ) );
 } 
diff --git a/src/LightApp/LightApp_ModuleAction.h b/src/LightApp/LightApp_ModuleAction.h
index 47c4a85ae..56f2efa97 100755
--- a/src/LightApp/LightApp_ModuleAction.h
+++ b/src/LightApp/LightApp_ModuleAction.h
@@ -40,6 +40,7 @@ class LIGHTAPP_EXPORT LightApp_ModuleAction : public QtxAction
 private:
   class ActionSet;
   class ComboAction;
+  class ActivateEvent;
 
 public:
   enum { None = 0x00, Buttons = 0x01, ComboItem = 0x02, All = Buttons | ComboItem };
@@ -67,7 +68,9 @@ protected:
   virtual void     addedTo( QWidget* );
   virtual void     removedFrom( QWidget* );
 
-signals:
+  virtual bool     event( QEvent* );
+
+Q_SIGNALS:
   void             moduleActivated( const QString& );
 
 private:
@@ -99,11 +102,11 @@ public:
 
   QList<QtxComboBox*> widgets() const;
 
+Q_SIGNALS:
+  void                activatedId( int );
+
 protected:
   virtual QWidget*    createWidget( QWidget* );
-
-signals:
-  void                activatedId( int );
 };
 
 #endif // LIGHTAPP_MODULEACTION_H
-- 
2.39.2