Close extra map views when changing project

Author: nyalldawson

src/app/qgisapp.cpp

@@ -3150,9 +3150,21 @@ QgsMapCanvas *QgisApp::createNewMapCanvas( const QString &name )
 
   addDockWidget( Qt::RightDockWidgetArea, mapCanvasWidget );
   mapCanvas->freeze( false );
+  markDirty();
+  connect( mapCanvasWidget, &QgsMapCanvasDockWidget::closed, this, &QgisApp::markDirty );
   return mapCanvas;
 }
 
+void QgisApp::closeAdditionalMapCanvases()
+{
+  freezeCanvases( true ); // closing docks may cause canvases to resize, and we don't want a map refresh occurring
+  Q_FOREACH ( QgsMapCanvasDockWidget *w, findChildren< QgsMapCanvasDockWidget * >() )
+  {
+    w->closeWithoutWarning();
+  }
+  freezeCanvases( false );
+}
+
 void QgisApp::freezeCanvases( bool frozen )
 {
   Q_FOREACH ( QgsMapCanvas *canvas, mapCanvases() )
@@ -9794,6 +9806,8 @@ void QgisApp::closeProject()
   mLegendExpressionFilterButton->setChecked( false );
   mActionFilterLegend->setChecked( false );
 
+  closeAdditionalMapCanvases();
+
   deletePrintComposers();
   removeAnnotationItems();
   // clear out any stuff from project

src/app/qgisapp.h

@@ -239,6 +239,12 @@ class APP_EXPORT QgisApp : public QMainWindow, private Ui::MainWindow
     //! Create a new map canvas with the specified unique \a name
     QgsMapCanvas *createNewMapCanvas( const QString &name );
 
+    /**
+     * Closes any additional map canvases. The main map canvas will not
+     * be affected.
+     */
+    void closeAdditionalMapCanvases();
+
     /**
      * Freezes all map canvases (or thaws them if the \a frozen argument is false).
      */

src/app/qgsmapcanvasdockwidget.cpp

@@ -44,9 +44,15 @@ QgsMapCanvas *QgsMapCanvasDockWidget::mapCanvas()
   return mMapCanvas;
 }
 
+void QgsMapCanvasDockWidget::closeWithoutWarning()
+{
+  mShowCloseWarning = false;
+  close();
+}
+
 void QgsMapCanvasDockWidget::closeEvent( QCloseEvent *event )
 {
-  if ( mMapCanvas->layerCount() > 0
+  if ( mShowCloseWarning && mMapCanvas->layerCount() > 0
        && QMessageBox::question( this, tr( "Close map view" ),
                                  tr( "Are you sure you want to close this map view?" ), QMessageBox::Yes | QMessageBox::No, QMessageBox::No ) == QMessageBox::No )
   {

src/app/qgsmapcanvasdockwidget.h

@@ -33,6 +33,11 @@ class APP_EXPORT QgsMapCanvasDockWidget : public QgsDockWidget, private Ui::QgsM
      */
     QgsMapCanvas *mapCanvas();
 
+    /**
+     * Closes the dock, bypassing the usual warning prompt.
+     */
+    void closeWithoutWarning();
+
   protected:
 
     virtual void closeEvent( QCloseEvent *event ) override;
@@ -44,6 +49,7 @@ class APP_EXPORT QgsMapCanvasDockWidget : public QgsDockWidget, private Ui::QgsM
   private:
 
     QgsMapCanvas *mMapCanvas = nullptr;
+    bool mShowCloseWarning = true;
 
 
 };