ENH : adding a method to remove observer

WARNING : code not clean QtProgressBar::ClearObserver()

Modules/Wrappers/QtWidget/include/itkQtProgressBar.h

@@ -52,10 +52,11 @@ public:
   void ProcessEvent(itk::Object * caller, const itk::EventObject & event );
   void ConstProcessEvent(const itk::Object * caller, const itk::EventObject & event );
 
-
   /** Manage a Progress event */
   void Observe( itk::Object *caller );
 
+  void ClearObserver();
+
 signals:
   void SetValueChanged(int);
 

Modules/Wrappers/QtWidget/include/otbWrapperQtWidgetSimpleProgressReport.h

@@ -61,6 +61,7 @@ public slots:
   void AddNewProcessToReport();
 
 private:
+  void ClearEvent();
   QtWidgetSimpleProgressReport(const QtWidgetSimpleProgressReport&); //purposely not implemented
   void operator=(const QtWidgetSimpleProgressReport&); //purposely not
                                                        //implemented

Modules/Wrappers/QtWidget/src/itkQtProgressBar.cxx

@@ -98,4 +98,24 @@ QtProgressBar::Observe( itk::Object *caller )
   m_Caller->AddObserver(  itk::ProgressEvent(), m_RedrawCommand.GetPointer() );
 }
 
+void
+QtProgressBar::ClearObserver()
+{
+  if ( m_Caller->HasObserver(itk::ProgressEvent()) )
+    {
+      unsigned int i(0);
+      while ( (m_Caller->GetCommand(i)) != (m_RedrawCommand.GetPointer()) )
+      {
+        ++i;
+        if (i>10)
+          std::cout<<"ERROR"<<std::endl;
+      }
+      std::cout<<i<<std::endl;
+      m_Caller->RemoveObserver(i);
+
+    }
+  m_Caller = nullptr;
+  // m_Caller->RemoveAllObservers();
+}
+
 } // end namespace fltk

Modules/Wrappers/QtWidget/src/otbWrapperQtWidgetSimpleProgressReport.cxx

@@ -78,12 +78,24 @@ QtWidgetSimpleProgressReport::ProcessEvent( itk::Object * itkNotUsed(caller),
     if(eventToWatch)
       {
       m_CurrentProcess = eventToWatch->GetProcess();
+      std::cout<<"process in the box : "<<m_CurrentProcess->GetNameOfClass()<<std::endl;
       m_CurrentDescription =  eventToWatch->GetProcessDescription();
+      std::cout<<"Description is : "<<m_CurrentDescription<<std::endl;
       emit AddNewProcessToReport();
       }
     }
 }
 
+void
+QtWidgetSimpleProgressReport::ClearEvent()
+{
+  std::cout<<"Cleaning event"<<std::endl;
+  m_CurrentProcess = nullptr;
+  m_CurrentDescription = "";
+  // emit AddNewProcessToReport();
+  m_Bar->ClearObserver();
+}
+
 void QtWidgetSimpleProgressReport::ReportProcess()
 {
   m_Bar->Observe(m_CurrentProcess);
@@ -93,6 +105,7 @@ void QtWidgetSimpleProgressReport::ReportProcess()
 
 void QtWidgetSimpleProgressReport::Init()
 {
+  ClearEvent();
   m_Bar->setValue(0);
   m_Label->setText("No process");
 }