Added a signal from canvas when it has refreshed

src/app/qgsmeasuredialog.cpp

@@ -57,7 +57,9 @@ QgsMeasureDialog::QgsMeasureDialog( QgsMeasureTool* tool, Qt::WFlags f )
   else
     mcbProjectionEnabled->setCheckState( Qt::Unchecked );
 
-  connect( mcbProjectionEnabled, SIGNAL( stateChanged( int ) ),
+  // Update whenever the canvas has refreshed. Maybe more often than needed,
+  // but at least every time any settings changes 
+  connect( mTool->canvas(), SIGNAL( mapCanvasRefreshed() ),
            this, SLOT( changeProjectionEnabledState() ) );
 
   updateUi();
@@ -298,6 +300,7 @@ void QgsMeasureDialog::convertMeasurement( double &measure, QGis::UnitType &u, b
 
 void QgsMeasureDialog::changeProjectionEnabledState()
 {
+  QgsDebugMsg( "Entering!" );
   // store value
   QSettings settings;
   if ( mcbProjectionEnabled->isChecked() )
@@ -354,6 +357,7 @@ void QgsMeasureDialog::changeProjectionEnabledState()
       b = false;
     }
   }
+  QgsDebugMsg( "Exiting!" );
 }
 
 void QgsMeasureDialog::configureDistanceArea()

src/app/qgsmeasuretool.cpp

@@ -48,6 +48,7 @@ QgsMeasureTool::QgsMeasureTool( QgsMapCanvas* canvas, bool measureArea )
 
 QgsMeasureTool::~QgsMeasureTool()
 {
+  delete mDialog;
   delete mRubberBand;
 }
 

src/gui/qgsmapcanvas.cpp

@@ -427,6 +427,10 @@ void QgsMapCanvas::refresh()
   }
 
   mDrawing = false;
+
+  // Done refreshing
+  emit mapCanvasRefreshed();
+
 } // refresh
 
 void QgsMapCanvas::updateMap()

src/gui/qgsmapcanvas.h

@@ -335,6 +335,10 @@ class GUI_EXPORT QgsMapCanvas : public QGraphicsView
     */
     void renderComplete( QPainter * );
 
+    /** Emitted when canvas finished a refresh request.
+	\note Added in 2.0 */
+    void mapCanvasRefreshed();
+
     /** Emitted when the canvas is about to be rendered.
       \note Added in 1.5 */
     void renderStarting();