- fix #7441

- reset unit settings to original ones when deactivating OTF projection

- added OTF status (on/off) to mesuredialog title

- resets prefered units and selected srs
- when OTF transfo is deselected, this resets the units value to the
  original ones

Author: vmora

src/app/qgsmeasuredialog.cpp

@@ -222,6 +222,7 @@ void QgsMeasureDialog::updateUi()
     toolTip += "<br> * " + tr( "Project CRS transformation is turned off." ) + " ";
     toolTip += tr( "Canvas units setting is taken from project properties setting (%1)." ).arg( QGis::tr( mCanvasUnits ) );
     toolTip += "<br> * " + tr( "Ellipsoidal calculation is not possible, as project CRS is undefined." );
+    setWindowTitle( tr("Measure (OTF off)"));
   }
   else
   {
@@ -235,6 +236,7 @@ void QgsMeasureDialog::updateUi()
       toolTip += "<br> * " + tr( "Project CRS transformation is turned on but ellipsoidal calculation is not selected." );
       toolTip += "<br> * " + tr( "The canvas units setting is taken from the project CRS (%1)." ).arg( QGis::tr( mCanvasUnits ) );
     }
+    setWindowTitle( tr("Measure (OTF on)"));
   }
 
   if (( mCanvasUnits == QGis::Meters && mDisplayUnits == QGis::Feet ) || ( mCanvasUnits == QGis::Feet && mDisplayUnits == QGis::Meters ) )

src/app/qgsprojectproperties.cpp

@@ -814,12 +814,35 @@ void QgsProjectProperties::on_cbxProjectionEnabled_toggled( bool onFlyEnabled )
   QString unitsOnFlyState = tr( "Canvas units (CRS transformation: %1)" );
   if ( !onFlyEnabled )
   {
-    if ( !mProjectSrsId )
+    // reset projection to default
+    const QMap<QString, QgsMapLayer*> &mapLayers = QgsMapLayerRegistry::instance()->mapLayers();
+
+    if ( mMapCanvas->currentLayer() )
+    {
+      mLayerSrsId = mMapCanvas->currentLayer()->crs().srsid();
+    }
+    else if ( mapLayers.size() > 0 )
     {
-      mProjectSrsId = projectionSelector->selectedCrsId();
+      mLayerSrsId = mapLayers.begin().value()->crs().srsid();
     }
+    else
+    {
+      mLayerSrsId = mProjectSrsId;
+    }
+    mProjectSrsId = mLayerSrsId;
     projectionSelector->setSelectedCrsId( mLayerSrsId );
 
+    QgsCoordinateReferenceSystem srs( mLayerSrsId, QgsCoordinateReferenceSystem::InternalCrsId );
+    //set radio button to crs map unit type
+    QGis::UnitType units = srs.mapUnits();
+
+    radMeters->setChecked( units == QGis::Meters );
+    radFeet->setChecked( units == QGis::Feet );
+    radDegrees->setChecked( units == QGis::Degrees );
+
+    // unset ellipsoid
+    mEllipsoidIndex = 0;
+
     btnGrpMeasureEllipsoid->setTitle( measureOnFlyState.arg( tr( "OFF" ) ) );
     btnGrpMapUnits->setTitle( unitsOnFlyState.arg( tr( "OFF" ) ) );
   }
@@ -1452,7 +1475,6 @@ void QgsProjectProperties::updateEllipsoidUI( int newIndex )
       leSemiMajor->setToolTip( tr( "Select %1 from pull-down menu to adjust radii" ).arg( tr( "Parameters:" ) ) );
       leSemiMinor->setToolTip( tr( "Select %1 from pull-down menu to adjust radii" ).arg( tr( "Parameters:" ) ) );
     }
-    cmbEllipsoid->setCurrentIndex( mEllipsoidIndex ); // Not always necessary
     if ( mEllipsoidList[ mEllipsoidIndex ].acronym != GEO_NONE )
     {
       leSemiMajor->setText( QLocale::system().toString( myMajor, 'f', 3 ) );
@@ -1464,4 +1486,5 @@ void QgsProjectProperties::updateEllipsoidUI( int newIndex )
     cmbEllipsoid->setEnabled( false );
     cmbEllipsoid->setToolTip( tr( "Can only use ellipsoidal calculations when CRS transformation is enabled" ) );
   }
+  cmbEllipsoid->setCurrentIndex( mEllipsoidIndex ); // Not always necessary
 }