Show message in message bar if feture has no geometry / empty geometry

Author: mhugent

python/gui/qgsmapcanvas.sip

@@ -506,6 +506,9 @@ class QgsMapCanvas : QGraphicsView
     //! @note added in 2.12
     void layerStyleOverridesChanged();
 
+    //! emit a message (usually to be displayed in a message bar)
+    void messageEmitted( const QString& title, const QString& message, QgsMessageBar::MessageLevel = QgsMessageBar::INFO );
+
   protected:
     //! Overridden standard event to be gestures aware
     bool event( QEvent * e );

src/app/qgisapp.cpp

@@ -618,6 +618,8 @@ QgisApp::QgisApp( QSplashScreen *splash, bool restorePlugins, QWidget * parent,
 
   // "theMapCanvas" used to find this canonical instance later
   mMapCanvas = new QgsMapCanvas( centralWidget, "theMapCanvas" );
+  connect( mMapCanvas, SIGNAL( messageEmitted( const QString&, const QString&, QgsMessageBar::MessageLevel ) ),
+           this, SLOT( displayMessage( const QString&, const QString&, QgsMessageBar::MessageLevel ) ) );
   mMapCanvas->setWhatsThis( tr( "Map canvas. This is where raster and vector "
                                 "layers are displayed when added to the map" ) );
 
@@ -1032,6 +1034,8 @@ QgisApp::QgisApp()
   setupUi( this );
   mInternalClipboard = new QgsClipboard;
   mMapCanvas = new QgsMapCanvas();
+  connect( mMapCanvas, SIGNAL( messageEmitted( const QString&, const QString&, QgsMessageBar::MessageLevel ) ),
+           this, SLOT( displayMessage( const QString&, const QString&, QgsMessageBar::MessageLevel ) ) );
   mMapCanvas->freeze();
   mLayerTreeView = new QgsLayerTreeView( this );
   mUndoWidget = new QgsUndoWidget( nullptr, mMapCanvas );
@@ -9366,6 +9370,11 @@ void QgisApp::displayMapToolMessage( const QString& message, QgsMessageBar::Mess
   }
 }
 
+void QgisApp::displayMessage( const QString& title, const QString& message, QgsMessageBar::MessageLevel level )
+{
+  messageBar()->pushMessage( title, message, level, messageTimeout() );
+}
+
 void QgisApp::removeMapToolMessage()
 {
   // remove previous message

src/app/qgisapp.h

@@ -1084,6 +1084,7 @@ class APP_EXPORT QgisApp : public QMainWindow, private Ui::MainWindow
     void showRotation();
     void showStatusMessage( const QString& theMessage );
     void displayMapToolMessage( const QString& message, QgsMessageBar::MessageLevel level = QgsMessageBar::INFO );
+    void displayMessage( const QString& title, const QString& message, QgsMessageBar::MessageLevel level );
     void removeMapToolMessage();
     void updateMouseCoordinatePrecision();
     void hasCrsTransformEnabled( bool theFlag );

src/gui/attributetable/qgsdualview.cpp

@@ -356,7 +356,7 @@ void QgsDualView::viewWillShowContextMenu( QMenu* menu, const QModelIndex& atInd
   QgsVectorLayer* vl = mFilterModel->layer();
   QgsMapCanvas* canvas = mFilterModel->mapCanvas();
   if ( canvas && vl && vl->geometryType() != QGis::NoGeometry )
-  {  
+  {
     menu->addAction( tr( "Zoom to feature" ), this, SLOT( zoomToCurrentFeature() ) );
   }
 

src/gui/qgsmapcanvas.cpp

@@ -1084,8 +1084,19 @@ void QgsMapCanvas::zoomToFeatureId( QgsVectorLayer* layer, QgsFeatureId id )
   }
 
   QgsGeometry* geom = fet.geometry();
+
+  QString errorMessage;
   if ( !geom || !geom->geometry() )
   {
+    errorMessage = tr( "Feature does not have a geometry" );
+  }
+  else if ( geom->geometry()->isEmpty() )
+  {
+    errorMessage = tr( "Feature geometry is empty" );
+  }
+  if ( !errorMessage.isEmpty() )
+  {
+    emit messageEmitted( tr( "Zoom to feature id failed" ), errorMessage, QgsMessageBar::WARNING );
     return;
   }
 

src/gui/qgsmapcanvas.h

@@ -22,6 +22,7 @@
 
 #include "qgsexpressioncontext.h"
 #include "qgsfeature.h"
+#include "qgsmessagebar.h"
 #include "qgsrectangle.h"
 #include "qgspoint.h"
 #include "qgis.h"
@@ -586,6 +587,9 @@ class GUI_EXPORT QgsMapCanvas : public QGraphicsView
     //! @note added in 2.12
     void layerStyleOverridesChanged();
 
+    //! emit a message (usually to be displayed in a message bar)
+    void messageEmitted( const QString& title, const QString& message, QgsMessageBar::MessageLevel = QgsMessageBar::INFO );
+
   protected:
 #ifdef HAVE_TOUCH
     //! Overridden standard event to be gestures aware