Shutdown safety. (Potentially KICAD-TJK.)

common/widgets/lib_tree.cpp

@@ -290,6 +290,9 @@ void LIB_TREE::ShutdownPreviews()
 
     if( m_previewWindow )
     {
+        // Shutdown the preview window's canvas
+        m_adapter->ShutdownPreview( m_previewWindow );
+
         m_previewWindow->Hide();
         m_previewWindow->Destroy();
         m_previewWindow = nullptr;

eeschema/sch_preview_panel.h

@@ -55,7 +55,6 @@ public:
 
     SCH_RENDER_SETTINGS* GetRenderSettings() const;
 
-
 protected:
 
     void onPaint( wxPaintEvent& WXUNUSED( aEvent ) ) override;

eeschema/symbol_tree_synchronizing_adapter.cpp

@@ -381,11 +381,12 @@ bool SYMBOL_TREE_SYNCHRONIZING_ADAPTER::HasPreview( const wxDataViewItem& aItem
 }
 
 
+static const wxString c_previewName = wxS( "symHoverPreview" );
+
+
 void SYMBOL_TREE_SYNCHRONIZING_ADAPTER::ShowPreview( wxWindow*             aParent,
                                                      const wxDataViewItem& aItem )
 {
-    static const wxString c_previewName = wxS( "symHoverPreview" );
-
     LIB_TREE_NODE* node = ToNode( aItem );
     wxCHECK( node, /* void */ );
 
@@ -416,3 +417,15 @@ void SYMBOL_TREE_SYNCHRONIZING_ADAPTER::ShowPreview( wxWindow*             aPare
 
     preview->DisplaySymbol( node->m_LibId, node->m_Unit );
 }
+
+
+void SYMBOL_TREE_SYNCHRONIZING_ADAPTER::ShutdownPreview( wxWindow* aParent )
+{
+    wxWindow* previewWindow = wxWindow::FindWindowByName( c_previewName, aParent );
+
+    if( SYMBOL_PREVIEW_WIDGET* preview = dynamic_cast<SYMBOL_PREVIEW_WIDGET*>( previewWindow ) )
+    {
+        preview->GetCanvas()->SetEvtHandlerEnabled( false );
+        preview->GetCanvas()->StopDrawing();
+    }
+}

eeschema/symbol_tree_synchronizing_adapter.h

@@ -50,8 +50,9 @@ public:
 
     wxDataViewItem GetCurrentDataViewItem() override;
 
-    virtual bool HasPreview( const wxDataViewItem& aItem ) override;
-    virtual void ShowPreview( wxWindow* aParent, const wxDataViewItem& aItem ) override;
+    bool HasPreview( const wxDataViewItem& aItem ) override;
+    void ShowPreview( wxWindow* aParent, const wxDataViewItem& aItem ) override;
+    void ShutdownPreview( wxWindow* aParent ) override;
 
 protected:
     void updateLibrary( LIB_TREE_NODE_LIBRARY& aLibNode );

eeschema/widgets/symbol_preview_widget.h

@@ -60,6 +60,8 @@ public:
 
     void DisplayPart( LIB_SYMBOL* aSymbol, int aUnit, int aBodyStyle = 0 );
 
+    EDA_DRAW_PANEL_GAL* GetCanvas() const { return m_preview; }
+
 protected:
     void onSize( wxSizeEvent& aEvent );
 

include/lib_tree_model_adapter.h

@@ -265,6 +265,7 @@ public:
 
     virtual bool HasPreview( const wxDataViewItem& aItem ) { return false; }
     virtual void ShowPreview( wxWindow* aParent, const wxDataViewItem& aItem ) {}
+    virtual void ShutdownPreview( wxWindow* aParent ) {}
 
     TOOL_DISPATCHER* GetToolDispatcher() const { return m_parent->GetToolDispatcher(); }
 

pcbnew/fp_tree_synchronizing_adapter.cpp

@@ -333,10 +333,11 @@ bool FP_TREE_SYNCHRONIZING_ADAPTER::HasPreview( const wxDataViewItem& aItem )
 }
 
 
+static const wxString c_previewName = wxS( "fpHoverPreview" );
+
+
 void FP_TREE_SYNCHRONIZING_ADAPTER::ShowPreview( wxWindow* aParent, const wxDataViewItem& aItem )
 {
-    static const wxString c_previewName = wxS( "fpHoverPreview" );
-
     LIB_TREE_NODE* node = ToNode( aItem );
     wxCHECK( node, /* void */ );
 
@@ -358,4 +359,16 @@ void FP_TREE_SYNCHRONIZING_ADAPTER::ShowPreview( wxWindow* aParent, const wxData
     }
 
     preview->DisplayFootprint( node->m_LibId );
+}
+
+
+void FP_TREE_SYNCHRONIZING_ADAPTER::ShutdownPreview( wxWindow* aParent )
+{
+    wxWindow* previewWindow = wxWindow::FindWindowByName( c_previewName, aParent );
+
+    if( FOOTPRINT_PREVIEW_PANEL* preview = dynamic_cast<FOOTPRINT_PREVIEW_PANEL*>( previewWindow ) )
+    {
+        preview->GetCanvas()->SetEvtHandlerEnabled( false );
+        preview->GetCanvas()->StopDrawing();
+    }
 }

pcbnew/fp_tree_synchronizing_adapter.h

@@ -46,8 +46,9 @@ public:
 
     wxDataViewItem GetCurrentDataViewItem() override;
 
-    virtual bool HasPreview( const wxDataViewItem& aItem ) override;
-    virtual void ShowPreview( wxWindow* aParent, const wxDataViewItem& aItem ) override;
+    bool HasPreview( const wxDataViewItem& aItem ) override;
+    void ShowPreview( wxWindow* aParent, const wxDataViewItem& aItem ) override;
+    void ShutdownPreview( wxWindow* aParent ) override;
 
 protected:
     FP_TREE_SYNCHRONIZING_ADAPTER( FOOTPRINT_EDIT_FRAME* aFrame, FP_LIB_TABLE* aLibs );