Fix issue #7379: Crash when attribute table is closed after layer has been deleted

m-kuhn · m-kuhn · commit 9aea6adc0e80 · 2013-03-27T13:53:13.000+01:00
diff --git a/src/core/qgsvectorlayercache.cpp b/src/core/qgsvectorlayercache.cpp
@@ -27,6 +27,7 @@ QgsVectorLayerCache::QgsVectorLayerCache( QgsVectorLayer* layer, int cacheSize,
 
   connect( mLayer, SIGNAL( featureDeleted( QgsFeatureId ) ), SLOT( featureDeleted( QgsFeatureId ) ) );
   connect( mLayer, SIGNAL( featureAdded( QgsFeatureId ) ), SLOT( featureAdded( QgsFeatureId ) ) );
+  connect( mLayer, SIGNAL( layerDeleted() ), SLOT( layerDeleted() ) );
 
   setCacheGeometry( true );
   setCacheSubsetOfAttributes( mLayer->pendingAllAttributesList() );
@@ -228,6 +229,13 @@ void QgsVectorLayerCache::geometryChanged( QgsFeatureId fid, QgsGeometry& geom )
   }
 }
 
+void QgsVectorLayerCache::layerDeleted()
+{
+  emit ( cachedLayerDeleted() );
+
+  mLayer = NULL;
+}
+
 QgsFeatureIterator QgsVectorLayerCache::getFeatures( const QgsFeatureRequest &featureRequest )
 {
   QgsFeatureIterator it;
diff --git a/src/core/qgsvectorlayercache.h b/src/core/qgsvectorlayercache.h
@@ -209,13 +209,21 @@ class CORE_EXPORT QgsVectorLayerCache : public QObject
      */
     void progress( int i, bool& cancel );
 
+    /**
+     * @brief Is emitted when the cached layer is deleted. Is emitted when the cached layers layerDelete()
+     * signal is being emitted, but before the local reference to it has been set to NULL. So call to
+     * @link {layer()} will still return a valid pointer for cleanup purpose.
+     */
+    void cachedLayerDeleted();
+
   public slots:
     void attributeValueChanged( QgsFeatureId fid, int field, const QVariant& value );
     void featureDeleted( QgsFeatureId fid );
     void featureAdded( QgsFeatureId fid );
     void attributeAdded( int field );
     void attributeDeleted( int field );
     void geometryChanged( QgsFeatureId fid, QgsGeometry& geom );
+    void layerDeleted();
 
   private:
 
diff --git a/src/gui/attributetable/qgsattributetablefiltermodel.cpp b/src/gui/attributetable/qgsattributetablefiltermodel.cpp
@@ -241,6 +241,9 @@ void QgsAttributeTableFilterModel::announcedInvalidateFilter()
 
 void QgsAttributeTableFilterModel::generateListOfVisibleFeatures()
 {
+  if ( !layer() )
+    return;
+
   bool filter = false;
   QgsRectangle rect = mCanvas->mapRenderer()->mapToLayerCoordinates( layer(), mCanvas->extent() );
   QgsRenderContext renderContext;
diff --git a/src/gui/attributetable/qgsattributetablemodel.cpp b/src/gui/attributetable/qgsattributetablemodel.cpp
@@ -45,17 +45,21 @@ QgsAttributeTableModel::QgsAttributeTableModel( QgsVectorLayerCache *layerCache,
   connect( layer(), SIGNAL( featureDeleted( QgsFeatureId ) ), this, SLOT( featureDeleted( QgsFeatureId ) ) );
   connect( layer(), SIGNAL( attributeAdded( int ) ), this, SLOT( attributeAdded( int ) ) );
   connect( layer(), SIGNAL( attributeDeleted( int ) ), this, SLOT( attributeDeleted( int ) ) );
+  connect( mLayerCache, SIGNAL( cachedLayerDeleted() ), this, SLOT( layerDeleted() ) );
 }
 
 QgsAttributeTableModel::~QgsAttributeTableModel()
 {
-  const QgsFields& fields = layer()->pendingFields();
-  for ( int idx = 0; idx < fields.count(); ++idx )
+  if ( layer() )
   {
-    if ( layer()->editType( idx ) != QgsVectorLayer::ValueRelation )
-      continue;
+    const QgsFields& fields = layer()->pendingFields();
+    for ( int idx = 0; idx < fields.count(); ++idx )
+    {
+      if ( layer()->editType( idx ) != QgsVectorLayer::ValueRelation )
+        continue;
 
-    delete mValueMaps.take( idx );
+      delete mValueMaps.take( idx );
+    }
   }
 }
 
@@ -163,6 +167,15 @@ void QgsAttributeTableModel::layerDeleted()
   beginRemoveRows( QModelIndex(), 0, rowCount() - 1 );
   removeRows( 0, rowCount() );
   endRemoveRows();
+
+  const QgsFields& fields = layer()->pendingFields();
+  for ( int idx = 0; idx < fields.count(); ++idx )
+  {
+    if ( layer()->editType( idx ) != QgsVectorLayer::ValueRelation )
+      continue;
+
+    delete mValueMaps.take( idx );
+  }
 }
 
 void QgsAttributeTableModel::attributeValueChanged( QgsFeatureId fid, int idx, const QVariant &value )
@@ -393,6 +406,9 @@ int QgsAttributeTableModel::columnCount( const QModelIndex &parent ) const
 
 QVariant QgsAttributeTableModel::headerData( int section, Qt::Orientation orientation, int role ) const
 {
+  if ( !layer() )
+    return QVariant();
+
   if ( role == Qt::DisplayRole )
   {
     if ( orientation == Qt::Vertical ) //row

Original file line number	Diff line number	Diff line change
`@@ -27,6 +27,7 @@ QgsVectorLayerCache::QgsVectorLayerCache( QgsVectorLayer* layer, int cacheSize,`
`27`	`27`
`28`	`28`	`connect( mLayer, SIGNAL( featureDeleted( QgsFeatureId ) ), SLOT( featureDeleted( QgsFeatureId ) ) );`
`29`	`29`	`connect( mLayer, SIGNAL( featureAdded( QgsFeatureId ) ), SLOT( featureAdded( QgsFeatureId ) ) );`
	`30`	`+ connect( mLayer, SIGNAL( layerDeleted() ), SLOT( layerDeleted() ) );`
`30`	`31`
`31`	`32`	`setCacheGeometry( true );`
`32`	`33`	`setCacheSubsetOfAttributes( mLayer->pendingAllAttributesList() );`
`@@ -228,6 +229,13 @@ void QgsVectorLayerCache::geometryChanged( QgsFeatureId fid, QgsGeometry& geom )`
`228`	`229`	`}`
`229`	`230`	`}`
`230`	`231`
	`232`	`+void QgsVectorLayerCache::layerDeleted()`
	`233`	`+{`
	`234`	`+ emit ( cachedLayerDeleted() );`
	`235`	`+`
	`236`	`+ mLayer = NULL;`
	`237`	`+}`
	`238`	`+`
`231`	`239`	`QgsFeatureIterator QgsVectorLayerCache::getFeatures( const QgsFeatureRequest &featureRequest )`
`232`	`240`	`{`
`233`	`241`	`QgsFeatureIterator it;`
Original file line number	Diff line number	Diff line change
`@@ -241,6 +241,9 @@ void QgsAttributeTableFilterModel::announcedInvalidateFilter()`
`241`	`241`
`242`	`242`	`void QgsAttributeTableFilterModel::generateListOfVisibleFeatures()`
`243`	`243`	`{`
	`244`	`+ if ( !layer() )`
	`245`	`+ return;`
	`246`	`+`
`244`	`247`	`bool filter = false;`
`245`	`248`	`QgsRectangle rect = mCanvas->mapRenderer()->mapToLayerCoordinates( layer(), mCanvas->extent() );`
`246`	`249`	`QgsRenderContext renderContext;`