Merge branch 'macos-dvc-isdeleting'

Fix crash in wxDataViewModel::Cleared() under Mac.

See #22025.

include/wx/osx/dataview.h

@@ -259,11 +259,6 @@ public:
   {
     m_CustomRendererPtr = NewCustomRendererPtr;
   }
- // sets the flag indicating a deletion process:
-  void SetDeleting(bool deleting)
-  {
-    m_Deleting = deleting;
-  }
 
   void AdjustAutosizedColumns() const;
 
@@ -305,6 +300,9 @@ private:
                    // after the actual deletion of the item; then, native callback functions/delegates may try to update data of variables that are already deleted;
                    // if this flag is set all native variable update requests will be ignored
 
+  // This class can set (and reset) m_Deleting.
+  friend class wxOSXDVCScopedDeleter;
+
   void* m_cgContext; // pointer to core graphics context
 
   wxDataViewCustomRenderer* m_CustomRendererPtr; // pointer to a valid custom renderer while editing; this class does NOT own the pointer

samples/dataview/dataview.cpp

@@ -82,6 +82,7 @@ private:
 #endif // wxHAS_GENERIC_DATAVIEWCTRL
     void OnGetPageInfo(wxCommandEvent& event);
     void OnDisable(wxCommandEvent& event);
+    void OnClearMyMusicTreeModel(wxCommandEvent& event);
     void OnSetForegroundColour(wxCommandEvent& event);
     void OnIncIndent(wxCommandEvent& event);
     void OnDecIndent(wxCommandEvent& event);
@@ -398,6 +399,7 @@ enum
     ID_CLEARLOG = wxID_HIGHEST+1,
     ID_GET_PAGE_INFO,
     ID_DISABLE,
+    ID_CLEAR_MODEL,
     ID_BACKGROUND_COLOUR,
     ID_FOREGROUND_COLOUR,
     ID_CUSTOM_HEADER_ATTR,
@@ -479,6 +481,7 @@ wxBEGIN_EVENT_TABLE(MyFrame, wxFrame)
 
     EVT_MENU( ID_GET_PAGE_INFO, MyFrame::OnGetPageInfo )
     EVT_MENU( ID_DISABLE, MyFrame::OnDisable )
+    EVT_MENU( ID_CLEAR_MODEL, MyFrame::OnClearMyMusicTreeModel )
     EVT_MENU( ID_FOREGROUND_COLOUR, MyFrame::OnSetForegroundColour )
     EVT_MENU( ID_BACKGROUND_COLOUR, MyFrame::OnSetBackgroundColour )
     EVT_MENU( ID_CUSTOM_HEADER_ATTR, MyFrame::OnCustomHeaderAttr )
@@ -597,6 +600,7 @@ MyFrame::MyFrame(wxFrame *frame, const wxString &title, int x, int y, int w, int
     file_menu->Append(ID_CLEARLOG, "&Clear log\tCtrl-L");
     file_menu->Append(ID_GET_PAGE_INFO, "Show current &page info");
     file_menu->AppendCheckItem(ID_DISABLE, "&Disable\tCtrl-D");
+    file_menu->Append(ID_CLEAR_MODEL, "&Clear MyMusicTreeModel\tCtrl-W");
     file_menu->Append(ID_FOREGROUND_COLOUR, "Set &foreground colour...\tCtrl-S");
     file_menu->Append(ID_BACKGROUND_COLOUR, "Set &background colour...\tCtrl-B");
     file_menu->AppendCheckItem(ID_CUSTOM_HEADER_ATTR, "C&ustom header attributes");
@@ -1144,6 +1148,11 @@ void MyFrame::OnDisable(wxCommandEvent& event)
     m_ctrl[m_notebook->GetSelection()]->Enable(!event.IsChecked());
 }
 
+void MyFrame::OnClearMyMusicTreeModel(wxCommandEvent& WXUNUSED(event))
+{
+    m_music_model->Clear();
+}
+
 void MyFrame::OnSetForegroundColour(wxCommandEvent& WXUNUSED(event))
 {
     wxDataViewCtrl * const dvc = m_ctrl[m_notebook->GetSelection()];

samples/dataview/mymodels.cpp

@@ -145,6 +145,21 @@ void MyMusicTreeModel::Delete( const wxDataViewItem &item )
     // notify control
     ItemDeleted( parent, item );
 }
+void MyMusicTreeModel::Clear()
+{
+    m_pop       = NULL;
+    m_classical = NULL;
+    m_ninth     = NULL;
+
+    while (!m_root->GetChildren().IsEmpty())
+    {
+        MyMusicTreeModelNode* node = m_root->GetNthChild(0);
+        m_root->GetChildren().Remove(node);
+        delete node;
+    }
+
+    Cleared();
+}
 
 int MyMusicTreeModel::Compare( const wxDataViewItem &item1, const wxDataViewItem &item2,
                                unsigned int column, bool ascending ) const

samples/dataview/mymodels.h

@@ -136,6 +136,7 @@ public:
     void AddToClassical( const wxString &title, const wxString &artist,
                          unsigned int year );
     void Delete( const wxDataViewItem &item );
+    void Clear();
 
     wxDataViewItem GetNinthItem() const
     {

src/osx/cocoa/dataview.mm

@@ -551,6 +551,11 @@ outlineView:(NSOutlineView*)outlineView
 {
     wxUnusedVar(outlineView);
 
+    // See the comment in outlineView:objectValueForTableColumn:byItem: below:
+    // this function can also be called in the same circumstances.
+    if ( implementation->GetDataViewCtrl()->IsDeleting() )
+        return nil;
+
     if ((item == currentParentItem) &&
             (index < ((NSInteger) [self getChildCount])))
         return [self getChild:index];

src/osx/dataview_osx.cpp

@@ -49,6 +49,33 @@ wxString ConcatenateDataViewItemValues(wxDataViewCtrl const* dataViewCtrlPtr, wx
   return dataString;
 }
 
+// ============================================================================
+// wxOSXDVCScopedDeleter
+// ============================================================================
+
+// Helper class which exists only to reset m_Deleting on scope exit.
+class wxOSXDVCScopedDeleter
+{
+public:
+    explicit wxOSXDVCScopedDeleter(wxDataViewCtrl* dvc) :
+        m_dvc(dvc),
+        m_valueOrig(m_dvc->m_Deleting)
+    {
+        m_dvc->m_Deleting = true;
+    }
+
+    ~wxOSXDVCScopedDeleter()
+    {
+        m_dvc->m_Deleting = m_valueOrig;
+    }
+
+private:
+    wxDataViewCtrl* const m_dvc;
+    const bool m_valueOrig;
+
+    wxDECLARE_NO_COPY_CLASS(wxOSXDVCScopedDeleter);
+};
+
 // ============================================================================
 // wxOSXDataViewModelNotifier
 // ============================================================================
@@ -192,42 +219,33 @@ bool wxOSXDataViewModelNotifier::ItemsChanged(wxDataViewItemArray const& items)
 
 bool wxOSXDataViewModelNotifier::ItemDeleted(wxDataViewItem const& parent, wxDataViewItem const& item)
 {
-  bool noFailureFlag;
-
-
   wxCHECK_MSG(item.IsOk(),false,"To be deleted item is invalid.");
  // when this method is called and currently an item is being edited this item may have already been deleted in the model (the passed item and the being edited item have
  // not to be identical because the being edited item might be below the passed item in the hierarchy);
  // to prevent the control trying to ask the model to update an already deleted item the control is informed that currently a deleting process
  // has been started and that variables can currently not be updated even when requested by the system:
-  m_DataViewCtrlPtr->SetDeleting(true);
+  wxOSXDVCScopedDeleter setDeleting(m_DataViewCtrlPtr);
-  noFailureFlag = m_DataViewCtrlPtr->GetDataViewPeer()->Remove(parent);
+
- // enable automatic updating again:
+  bool ok = m_DataViewCtrlPtr->GetDataViewPeer()->Remove(parent);
-  m_DataViewCtrlPtr->SetDeleting(false);
 
   AdjustAutosizedColumns();
- // done:
+
-  return noFailureFlag;
+  return ok;
 }
 
 bool wxOSXDataViewModelNotifier::ItemsDeleted(wxDataViewItem const& parent, wxDataViewItemArray const& WXUNUSED(items))
 {
-  bool noFailureFlag;
-
-
  // when this method is called and currently an item is being edited this item may have already been deleted in the model (the passed item and the being edited item have
  // not to be identical because the being edited item might be below the passed item in the hierarchy);
  // to prevent the control trying to ask the model to update an already deleted item the control is informed that currently a deleting process
  // has been started and that variables can currently not be updated even when requested by the system:
-  m_DataViewCtrlPtr->SetDeleting(true);
+    wxOSXDVCScopedDeleter setDeleting(m_DataViewCtrlPtr);
  // delete all specified items:
-  noFailureFlag = m_DataViewCtrlPtr->GetDataViewPeer()->Remove(parent);
+    bool ok = m_DataViewCtrlPtr->GetDataViewPeer()->Remove(parent);
- // enable automatic updating again:
-  m_DataViewCtrlPtr->SetDeleting(false);
 
   AdjustAutosizedColumns();
- // done:
+
-  return noFailureFlag;
+  return ok;
 }
 
 bool wxOSXDataViewModelNotifier::ValueChanged(wxDataViewItem const& item, unsigned int col)
@@ -251,6 +269,8 @@ bool wxOSXDataViewModelNotifier::ValueChanged(wxDataViewItem const& item, unsign
 
 bool wxOSXDataViewModelNotifier::Cleared()
 {
+    // NOTE: See comments in ItemDeleted method above
+    wxOSXDVCScopedDeleter setDeleting(m_DataViewCtrlPtr);
     return m_DataViewCtrlPtr->GetDataViewPeer()->Reload();
 }