Fix for zonal statistics (ticket #4972)

mhugent · mhugent · commit 9f57650eafec · 2012-03-18T09:13:34.000+01:00
diff --git a/src/analysis/vector/qgszonalstatistics.cpp b/src/analysis/vector/qgszonalstatistics.cpp
@@ -109,9 +109,9 @@ int QgsZonalStatistics::calculateStatistics( QProgressDialog* p )
 
   //add the new count, sum, mean fields to the provider
   QList<QgsField> newFieldList;
-  QgsField countField( mAttributePrefix + "count", QVariant::Double );
-  QgsField sumField( mAttributePrefix + "sum", QVariant::Double );
-  QgsField meanField( mAttributePrefix + "mean", QVariant::Double );
+  QgsField countField( mAttributePrefix + "count", QVariant::Double, "double precision" );
+  QgsField sumField( mAttributePrefix + "sum", QVariant::Double, "double precision" );
+  QgsField meanField( mAttributePrefix + "mean", QVariant::Double, "double precision" );
   newFieldList.push_back( countField );
   newFieldList.push_back( sumField );
   newFieldList.push_back( meanField );
diff --git a/src/plugins/zonal_statistics/qgszonalstatisticsdialog.cpp b/src/plugins/zonal_statistics/qgszonalstatisticsdialog.cpp
@@ -68,7 +68,11 @@ void QgsZonalStatisticsDialog::insertAvailableLayers()
       QgsVectorLayer* vl = dynamic_cast<QgsVectorLayer*>( layer_it.value() );
       if ( vl && vl->geometryType() == QGis::Polygon )
       {
-        mPolygonLayerComboBox->addItem( vl->name(), QVariant( vl->id() ) );
+        QgsVectorDataProvider* provider  = vl->dataProvider();
+        if ( provider->capabilities() & QgsVectorDataProvider::AddAttributes )
+        {
+          mPolygonLayerComboBox->addItem( vl->name(), QVariant( vl->id() ) );
+        }
       }
     }
   }

Original file line number	Diff line number	Diff line change
`@@ -68,7 +68,11 @@ void QgsZonalStatisticsDialog::insertAvailableLayers()`
`68`	`68`	`QgsVectorLayer* vl = dynamic_cast<QgsVectorLayer*>( layer_it.value() );`
`69`	`69`	`if ( vl && vl->geometryType() == QGis::Polygon )`
`70`	`70`	`{`
`71`		`- mPolygonLayerComboBox->addItem( vl->name(), QVariant( vl->id() ) );`
	`71`	`+ QgsVectorDataProvider* provider = vl->dataProvider();`
	`72`	`+ if ( provider->capabilities() & QgsVectorDataProvider::AddAttributes )`
	`73`	`+ {`
	`74`	`+ mPolygonLayerComboBox->addItem( vl->name(), QVariant( vl->id() ) );`
	`75`	`+ }`
`72`	`76`	`}`
`73`	`77`	`}`
`74`	`78`	`}`