Fix crash on exit

nyalldawson · nyalldawson · commit c50cbfc98f11 · 2018-01-23T11:51:37.000+11:00
Since the snapping widget is destroyed *after* the project instance,
we need to avoid referring to the project after it's deleted.
diff --git a/src/app/qgssnappingwidget.cpp b/src/app/qgssnappingwidget.cpp
@@ -78,6 +78,10 @@ QgsSnappingWidget::QgsSnappingWidget( QgsProject *project, QgsMapCanvas *canvas,
   {
     model->resetLayerTreeModel();
   } );
+  connect( mProject, &QObject::destroyed, this, [ = ]
+  {
+    mLayerTreeView->setModel( nullptr );
+  } );
   // model->setFlags( 0 );
   mLayerTreeView->setModel( model );
   mLayerTreeView->resizeColumnToContents( 0 );
