Greatly speed up attribute table loading

nyalldawson · nyalldawson · commit ebd3e0d7a557 · 2017-05-23T09:35:14.000+10:00
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)
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

Original file line number	Diff line number	Diff line change
`@@ -67,7 +67,7 @@ QgsAttributeTableModel::QgsAttributeTableModel( QgsVectorLayerCache *layerCache,`
`67`	`67`	`connect( layer(), &QgsVectorLayer::attributeDeleted, this, &QgsAttributeTableModel::attributeDeleted );`
`68`	`68`	`connect( layer(), &QgsVectorLayer::updatedFields, this, &QgsAttributeTableModel::updatedFields );`
`69`	`69`	`connect( layer(), &QgsVectorLayer::editCommandEnded, this, &QgsAttributeTableModel::editCommandEnded );`
`70`		`- connect( mLayerCache, &QgsVectorLayerCache::featureAdded, this, &QgsAttributeTableModel::featureAdded );`
	`70`	`+ connect( mLayerCache, &QgsVectorLayerCache::featureAdded, this, [ = ]( QgsFeatureId id ) { featureAdded( id ); } );`
`71`	`71`	`connect( mLayerCache, &QgsVectorLayerCache::cachedLayerDeleted, this, &QgsAttributeTableModel::layerDeleted );`
`72`	`72`	`}`
`73`	`73`
`@@ -202,7 +202,7 @@ bool QgsAttributeTableModel::removeRows( int row, int count, const QModelIndex &`
`202`	`202`	`return true;`
`203`	`203`	`}`
`204`	`204`
`205`		`-void QgsAttributeTableModel::featureAdded( QgsFeatureId fid )`
	`205`	`+void QgsAttributeTableModel::featureAdded( QgsFeatureId fid, bool resettingModel )`
`206`	`206`	`{`
`207`	`207`	`QgsDebugMsgLevel( QString( "(%2) fid: %1" ).arg( fid ).arg( mFeatureRequest.filterType() ), 4 );`
`208`	`208`	`bool featOk = true;`
`@@ -230,10 +230,12 @@ void QgsAttributeTableModel::featureAdded( QgsFeatureId fid )`
`230`	`230`	`if ( ! mIdRowMap.contains( fid ) )`
`231`	`231`	`{`
`232`	`232`	`int n = mRowIdMap.size();`
`233`		`- beginInsertRows( QModelIndex(), n, n );`
	`233`	`+ if ( !resettingModel )`
	`234`	`+ beginInsertRows( QModelIndex(), n, n );`
`234`	`235`	`mIdRowMap.insert( fid, n );`
`235`	`236`	`mRowIdMap.insert( n, fid );`
`236`		`- endInsertRows();`
	`237`	`+ if ( !resettingModel )`
	`238`	`+ endInsertRows();`
`237`	`239`	`reload( index( rowCount() - 1, 0 ), index( rowCount() - 1, columnCount() ) );`
`238`	`240`	`}`
`239`	`241`	`}`
`@@ -430,7 +432,7 @@ void QgsAttributeTableModel::loadLayer()`
`430`	`432`
`431`	`433`	`t.restart();`
`432`	`434`	`}`
`433`		`- featureAdded( mFeat.id() );`
	`435`	`+ featureAdded( mFeat.id(), true );`
`434`	`436`	`}`
`435`	`437`
`436`	`438`	`emit finished();`