Eeschema: Fix a subtle bug in SYMBOL_PREVIEW_WIDGET.

The dialog was using a LIB_ALIAS from library cache to show the symbol to the canvas without making a local copy.
Unfortunately, the library viewer is doing the same thing.

Now the GAL is used in Eeschema, a link to the VIEW used by the GAL canvas is stored in this class.
When The selector symbol dialog is used to choose a symbol to display in the Library viewer,
a race condition between the Library viewer GAL canvas and the dtor dialog that destroyed this link in the same instancied class.

Now, the SYMBOL_PREVIEW_WIDGET used in the dialog works on a local copy of the symbol to display.

eeschema/viewlib_frame.cpp

@@ -603,8 +603,7 @@ void LIB_VIEW_FRAME::ClickOnCmpList( wxCommandEvent& event )
 
 void LIB_VIEW_FRAME::SetSelectedComponent( const wxString& aComponentName )
 {
-    // Aren't component names case sensitive now?
+    if( m_entryName != aComponentName )
-    if( m_entryName.CmpNoCase( aComponentName ) != 0 )
     {
         m_entryName = aComponentName;
 
@@ -621,8 +620,8 @@ void LIB_VIEW_FRAME::SetSelectedComponent( const wxString& aComponentName )
             m_selection_changed = false;
         }
 
-        Zoom_Automatique( false );
         updatePreviewSymbol();
+        Zoom_Automatique( false );
     }
 }
 

eeschema/viewlibs.cpp

@@ -45,29 +45,31 @@
 void LIB_VIEW_FRAME::OnSelectSymbol( wxCommandEvent& aEvent )
 {
     std::unique_lock<std::mutex> dialogLock( DIALOG_CHOOSE_COMPONENT::g_Mutex, std::defer_lock );
-    wxString                     dialogTitle;
-    SYMBOL_LIB_TABLE*            libs = Prj().SchSymbolLibTable();
 
     // One CHOOSE_COMPONENT dialog at a time.  User probaby can't handle more anyway.
     if( !dialogLock.try_lock() )
         return;
 
     // Container doing search-as-you-type.
+    SYMBOL_LIB_TABLE* libs = Prj().SchSymbolLibTable();
     auto adapterPtr( SYMBOL_TREE_MODEL_ADAPTER::Create( libs ) );
     auto adapter = static_cast<SYMBOL_TREE_MODEL_ADAPTER*>( adapterPtr.get() );
 
     const auto libNicknames = libs->GetLogicalLibs();
-
     adapter->AddLibraries( libNicknames, this );
 
+    LIB_ID id;
+    int unit;
+
+    wxString dialogTitle;
     dialogTitle.Printf( _( "Choose Symbol (%d items loaded)" ), adapter->GetItemCount() );
+
     DIALOG_CHOOSE_COMPONENT dlg( this, dialogTitle, adapterPtr, m_convert, false, false, false );
 
     if( dlg.ShowQuasiModal() == wxID_CANCEL )
         return;
 
-    int unit;
+    id = dlg.GetSelectedLibId( &unit );
-    LIB_ID id = dlg.GetSelectedLibId( &unit );
 
     if( !id.IsValid() )
         return;
@@ -75,8 +77,6 @@ void LIB_VIEW_FRAME::OnSelectSymbol( wxCommandEvent& aEvent )
     SetSelectedLibrary( id.GetLibNickname() );
     SetSelectedComponent( id.GetLibItemName() );
     SetUnitAndConvert( unit, 1 );
-
-    Zoom_Automatique( false );
 }
 
 

eeschema/widgets/symbol_preview_widget.cpp

@@ -80,6 +80,8 @@ SYMBOL_PREVIEW_WIDGET::~SYMBOL_PREVIEW_WIDGET()
 {
     if( m_previewItem )
         m_preview->GetView()->Remove( m_previewItem );
+
+    delete m_previewItem;
 }
 
 
@@ -149,6 +151,7 @@ void SYMBOL_PREVIEW_WIDGET::DisplaySymbol( const LIB_ID& aSymbolID, int aUnit )
     if( m_previewItem )
     {
         view->Remove( m_previewItem );
+        delete m_previewItem;
         m_previewItem = nullptr;
     }
 
@@ -166,11 +169,11 @@ void SYMBOL_PREVIEW_WIDGET::DisplaySymbol( const LIB_ID& aSymbolID, int aUnit )
         // For symbols having a De Morgan body style, use the first style
         settings->m_ShowConvert = part->HasConversion() ? 1 : 0;
 
-        view->Add( alias );
+        m_previewItem = new LIB_ALIAS( *alias, part );
-        m_previewItem = alias;
+        view->Add( m_previewItem );
 
         // Get the symbole size, in internal units
-        m_itemBBox = alias->GetPart()->GetUnitBoundingBox( aUnit, 0 );
+        m_itemBBox = part->GetUnitBoundingBox( aUnit, 0 );
 
         // Calculate the draw scale to fit the drawing area
         fitOnDrawArea();
@@ -190,6 +193,7 @@ void SYMBOL_PREVIEW_WIDGET::DisplayPart( LIB_PART* aPart, int aUnit )
     if( m_previewItem )
     {
         view->Remove( m_previewItem );
+        delete m_previewItem;
         m_previewItem = nullptr;
     }
 
@@ -203,9 +207,8 @@ void SYMBOL_PREVIEW_WIDGET::DisplayPart( LIB_PART* aPart, int aUnit )
         // For symbols having a De Morgan body style, use the first style
         auto settings = static_cast<KIGFX::SCH_RENDER_SETTINGS*>( view->GetPainter()->GetSettings() );
         settings->m_ShowConvert = aPart->HasConversion() ? 1 : 0;
-
+        m_previewItem = new LIB_PART( *aPart );
-        view->Add( aPart );
+        view->Add( m_previewItem );
-        m_previewItem = aPart;
 
         // Get the symbole size, in internal units
         m_itemBBox = aPart->GetUnitBoundingBox( aUnit, 0 );

eeschema/widgets/symbol_preview_widget.h

@@ -75,8 +75,12 @@ private:
     wxStaticText*              m_status;
     wxSizer*                   m_statusSizer;
 
+    /** a local copy of the LIB_ALIAS or the LIB_PART to display on the canvas
+     */
     EDA_ITEM*                  m_previewItem;
-    BOX2I                      m_itemBBox;      // The size of the current item
+
+    /// The bounding box of the current item
+    BOX2I                      m_itemBBox;
 };