Greatly speed up attribute table loading

Don't advise for rows added when a model reset is in progress. Otherwise the rows are tested for sort order, etc triggering a bunch of useless calculations, given that the model is in the process of being reset anyway. Tested using a 150k point shapefile, decreased attribute table load times from 50+ seconds to 4 seconds. Refs #16577, #16239 (forward port from b97a980)
qgis · May 22, 2017 · ebd3e0d · ebd3e0d
1 parent 48ecee5
commit ebd3e0d
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Showing 2 changed files with 10 additions and 6 deletions.
diff --git a/src/gui/attributetable/qgsattributetablemodel.cpp b/src/gui/attributetable/qgsattributetablemodel.cpp
@@ -67,7 +67,7 @@ QgsAttributeTableModel::QgsAttributeTableModel( QgsVectorLayerCache *layerCache,
   connect( layer(), &QgsVectorLayer::attributeDeleted, this, &QgsAttributeTableModel::attributeDeleted );
   connect( layer(), &QgsVectorLayer::updatedFields, this, &QgsAttributeTableModel::updatedFields );
   connect( layer(), &QgsVectorLayer::editCommandEnded, this, &QgsAttributeTableModel::editCommandEnded );
-  connect( mLayerCache, &QgsVectorLayerCache::featureAdded, this, &QgsAttributeTableModel::featureAdded );
+  connect( mLayerCache, &QgsVectorLayerCache::featureAdded, this, [ = ]( QgsFeatureId id ) { featureAdded( id ); } );
   connect( mLayerCache, &QgsVectorLayerCache::cachedLayerDeleted, this, &QgsAttributeTableModel::layerDeleted );
 }
 
@@ -202,7 +202,7 @@ bool QgsAttributeTableModel::removeRows( int row, int count, const QModelIndex &
   return true;
 }
 
-void QgsAttributeTableModel::featureAdded( QgsFeatureId fid )
+void QgsAttributeTableModel::featureAdded( QgsFeatureId fid, bool resettingModel )
 {
   QgsDebugMsgLevel( QString( "(%2) fid: %1" ).arg( fid ).arg( mFeatureRequest.filterType() ), 4 );
   bool featOk = true;
@@ -230,10 +230,12 @@ void QgsAttributeTableModel::featureAdded( QgsFeatureId fid )
     if ( ! mIdRowMap.contains( fid ) )
     {
       int n = mRowIdMap.size();
-      beginInsertRows( QModelIndex(), n, n );
+      if ( !resettingModel )
+        beginInsertRows( QModelIndex(), n, n );
       mIdRowMap.insert( fid, n );
       mRowIdMap.insert( n, fid );
-      endInsertRows();
+      if ( !resettingModel )
+        endInsertRows();
       reload( index( rowCount() - 1, 0 ), index( rowCount() - 1, columnCount() ) );
     }
   }
@@ -430,7 +432,7 @@ void QgsAttributeTableModel::loadLayer()
 
       t.restart();
     }
-    featureAdded( mFeat.id() );
+    featureAdded( mFeat.id(), true );
   }
 
   emit finished();

diff --git a/src/gui/attributetable/qgsattributetablemodel.h b/src/gui/attributetable/qgsattributetablemodel.h
@@ -313,8 +313,10 @@ class GUI_EXPORT QgsAttributeTableModel: public QAbstractTableModel
     /**
      * Launched when a feature has been added
      * \param fid feature id
+     * \param resettingModel set to true if model is in the process of being reset
+     * and the normal begin/EndInsertRows calls should not be made
      */
-    virtual void featureAdded( QgsFeatureId fid );
+    virtual void featureAdded( QgsFeatureId fid, bool resettingModel = false );
 
     /**
      * Launched when layer has been deleted