GerbView: fix a few issues with layer selection / info synchronization

Fixes: lp:1754135
* https://bugs.launchpad.net/kicad/+bug/1754135

gerbview/gerbview_frame.cpp

@@ -206,7 +206,6 @@ GERBVIEW_FRAME::GERBVIEW_FRAME( KIWAY* aKiway, wxWindow* aParent ):
 
     SetActiveLayer( 0, true );
     Zoom_Automatique( false );           // Gives a default zoom value
-    UpdateTitleAndInfo();
 
     EDA_DRAW_PANEL_GAL::GAL_TYPE canvasType = loadCanvasTypeSetting();
 
@@ -333,7 +332,7 @@ bool GERBVIEW_FRAME::OpenProjectFiles( const std::vector<wxString>& aFileSet, in
 
         int layer = 0;
 
-        for( unsigned i=0;  i<limit;  ++i, ++layer )
+        for( unsigned i = 0; i < limit; ++i, ++layer )
         {
             SetActiveLayer( layer );
 
@@ -353,8 +352,6 @@ bool GERBVIEW_FRAME::OpenProjectFiles( const std::vector<wxString>& aFileSet, in
 
     Zoom_Automatique( true );        // Zoom fit in frame
 
-    UpdateTitleAndInfo();
-
     return true;
 }
 
@@ -576,7 +573,6 @@ int GERBVIEW_FRAME::getNextAvailableLayer( int aLayer ) const
 void GERBVIEW_FRAME::syncLayerWidget()
 {
     m_LayersManager->SelectLayer( GetActiveLayer() );
-    UpdateTitleAndInfo();
 }
 
 
@@ -599,8 +595,6 @@ void GERBVIEW_FRAME::syncLayerBox( bool aRebuildLayerBox )
         m_DCodeSelector->SetDCodeSelection( dcodeSelected );
         m_DCodeSelector->Enable( gerber != NULL );
     }
-
-    UpdateTitleAndInfo();
 }
 
 
@@ -978,6 +972,8 @@ void GERBVIEW_FRAME::SetActiveLayer( int aLayer, bool doLayerWidgetUpdate )
     if( doLayerWidgetUpdate )
         m_LayersManager->SelectLayer( GetActiveLayer() );
 
+    UpdateTitleAndInfo();
+
     if( IsGalCanvasActive() )
     {
         m_toolManager->RunAction( GERBVIEW_ACTIONS::layerChanged );       // notify other tools

gerbview/job_file_reader.cpp

@@ -195,10 +195,10 @@ bool GERBVIEW_FRAME::LoadGerberJobFile( const wxString& aFullFileName )
         }
     }
 
-    Zoom_Automatique( false );
-
     SortLayersByX2Attributes();
 
+    SetActiveLayer( 0 );
+
     if( !msg.IsEmpty() )
     {
         wxSafeYield();  // Allows slice of time to redraw the screen