[attribute form] Significant speed boost when loading relation editor…

… widgets (#42906)
qgis · Apr 23, 2021 · 1db625b · 1db625b
1 parent 74552a5
commit 1db625b
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Showing 3 changed files with 62 additions and 39 deletions.
diff --git a/src/gui/attributetable/qgsdualview.cpp b/src/gui/attributetable/qgsdualview.cpp
@@ -123,6 +123,9 @@ void QgsDualView::init( QgsVectorLayer *layer, QgsMapCanvas *mapCanvas, const Qg
   if ( !layer )
     return;
 
+  delete mAttributeForm;
+  mAttributeForm = nullptr;
+
   mLayer = layer;
   mEditorContext = context;
 
@@ -133,10 +136,28 @@ void QgsDualView::init( QgsVectorLayer *layer, QgsMapCanvas *mapCanvas, const Qg
 
   mTableView->setModel( mFilterModel );
   mFeatureListView->setModel( mFeatureListModel );
-  delete mAttributeForm;
-  mAttributeForm = new QgsAttributeForm( mLayer, mTempAttributeFormFeature, mEditorContext );
-  mTempAttributeFormFeature = QgsFeature();
-  if ( !context.parentContext() )
+
+  connect( mFilterModel, &QgsAttributeTableFilterModel::sortColumnChanged, this, &QgsDualView::onSortColumnChanged );
+
+  if ( mFeatureListPreviewButton->defaultAction() )
+    mFeatureListView->setDisplayExpression( mDisplayExpression );
+  else
+    columnBoxInit();
+
+  // This slows down load of the attribute table heaps and uses loads of memory.
+  //mTableView->resizeColumnsToContents();
+
+  if ( mFeatureListModel->rowCount( ) > 0 )
+    mFeatureListView->setEditSelection( QgsFeatureIds() << mFeatureListModel->data( mFeatureListModel->index( 0, 0 ), QgsFeatureListModel::Role::FeatureRole ).value<QgsFeature>().id() );
+
+}
+
+void QgsDualView::initAttributeForm( const QgsFeature &feature )
+{
+  Q_ASSERT( !mAttributeForm );
+
+  mAttributeForm = new QgsAttributeForm( mLayer, feature, mEditorContext );
+  if ( !mEditorContext.parentContext() )
   {
     mAttributeEditorScrollArea = new QgsScrollArea();
     mAttributeEditorScrollArea->setWidgetResizable( true );
@@ -169,19 +190,6 @@ void QgsDualView::init( QgsVectorLayer *layer, QgsMapCanvas *mapCanvas, const Qg
   } );
 
   connect( mMasterModel, &QgsAttributeTableModel::modelChanged, mAttributeForm, &QgsAttributeForm::refreshFeature );
-  connect( mFilterModel, &QgsAttributeTableFilterModel::sortColumnChanged, this, &QgsDualView::onSortColumnChanged );
-
-  if ( mFeatureListPreviewButton->defaultAction() )
-    mFeatureListView->setDisplayExpression( mDisplayExpression );
-  else
-    columnBoxInit();
-
-  // This slows down load of the attribute table heaps and uses loads of memory.
-  //mTableView->resizeColumnsToContents();
-
-  if ( mFeatureListModel->rowCount( ) > 0 )
-    mFeatureListView->setEditSelection( QgsFeatureIds() << mFeatureListModel->data( mFeatureListModel->index( 0, 0 ), QgsFeatureListModel::Role::FeatureRole ).value<QgsFeature>().id() );
-
 }
 
 void QgsDualView::columnBoxInit()
@@ -614,6 +622,9 @@ void QgsDualView::filterError( const QString &errorMessage )
 
 void QgsDualView::featureListAboutToChangeEditSelection( bool &ok )
 {
+  if ( !mAttributeForm )
+    return;
+
   if ( mLayer->isEditable() && !mAttributeForm->save() )
     ok = false;
 }
@@ -622,7 +633,7 @@ void QgsDualView::featureListCurrentEditSelectionChanged( const QgsFeature &feat
 {
   if ( !mAttributeForm )
   {
-    mTempAttributeFormFeature = feat;
+    initAttributeForm( feat );
   }
   else if ( !mLayer->isEditable() || mAttributeForm->save() )
   {
@@ -649,7 +660,7 @@ void QgsDualView::setCurrentEditSelection( const QgsFeatureIds &fids )
 
 bool QgsDualView::saveEditChanges()
 {
-  return mAttributeForm->save();
+  return mAttributeForm ? mAttributeForm->save() : false;
 }
 
 void QgsDualView::openConditionalStyles()
@@ -659,19 +670,27 @@ void QgsDualView::openConditionalStyles()
 
 void QgsDualView::setMultiEditEnabled( bool enabled )
 {
+  if ( !mAttributeForm )
+    return;
+
   if ( enabled )
   {
     mPreviousView = view();
     setView( AttributeEditor );
   }
   else
+  {
     setView( mPreviousView );
+  }
 
   mAttributeForm->setMode( enabled ? QgsAttributeEditorContext::MultiEditMode : QgsAttributeEditorContext::SingleEditMode );
 }
 
 void QgsDualView::toggleSearchMode( bool enabled )
 {
+  if ( !mAttributeForm )
+    return;
+
   if ( enabled )
   {
     setView( AttributeEditor );

diff --git a/src/gui/attributetable/qgsdualview.h b/src/gui/attributetable/qgsdualview.h
@@ -399,6 +399,13 @@ class GUI_EXPORT QgsDualView : public QStackedWidget, private Ui::QgsDualViewBas
 
   private:
 
+    /**
+     * Initialize the attribute form to a given \a feature.
+     *
+     * \since QGIS 3.20
+     */
+    void initAttributeForm( const QgsFeature &feature );
+
     /**
      * Initializes widgets which depend on the attributes of this layer
      */
@@ -435,9 +442,6 @@ class GUI_EXPORT QgsDualView : public QStackedWidget, private Ui::QgsDualViewBas
     QString mDisplayExpression;
     QgsAttributeTableConfig mConfig;
     QgsScrollArea *mAttributeEditorScrollArea = nullptr;
-    // If the current feature is set, while the form is still not initialized
-    // we will temporarily save it in here and set it on init
-    QgsFeature mTempAttributeFormFeature;
     QgsFeatureIds mLastFeatureSet;
     bool mBrowsingAutoPanScaleAllowed = true;
     ViewMode mPreviousView = AttributeTable;

diff --git a/src/gui/qgsrelationeditorwidget.cpp b/src/gui/qgsrelationeditorwidget.cpp
@@ -201,11 +201,6 @@ QgsRelationEditorWidget::QgsRelationEditorWidget( const QVariantMap &config, QWi
   mRelationLayout->setContentsMargins( 0, 0, 0, 0 );
   topLayout->addLayout( mRelationLayout );
 
-  mDualView = new QgsDualView( this );
-  mDualView->setView( mViewMode );
-
-  mRelationLayout->addWidget( mDualView );
-
   connect( mRootCollapsibleGroupBox, &QgsCollapsibleGroupBoxBasic::collapsedStateChanged, this, &QgsRelationEditorWidget::onCollapsedStateChanged );
   connect( mViewModeButtonGroup, static_cast<void ( QButtonGroup::* )( int )>( &QButtonGroup::buttonClicked ),
            this, static_cast<void ( QgsRelationEditorWidget::* )( int )>( &QgsRelationEditorWidget::setViewMode ) );
@@ -219,14 +214,20 @@ QgsRelationEditorWidget::QgsRelationEditorWidget( const QVariantMap &config, QWi
   connect( mUnlinkFeatureButton, &QAbstractButton::clicked, this, &QgsRelationEditorWidget::unlinkSelectedFeatures );
   connect( mZoomToFeatureButton, &QAbstractButton::clicked, this, &QgsRelationEditorWidget::zoomToSelectedFeatures );
 
-  connect( mDualView, &QgsDualView::showContextMenuExternally, this, &QgsRelationEditorWidget::showContextMenu );
-
   // Set initial state for add/remove etc. buttons
   updateButtons();
 }
 
 void QgsRelationEditorWidget::initDualView( QgsVectorLayer *layer, const QgsFeatureRequest &request )
 {
+  if ( !mDualView )
+  {
+    mDualView = new QgsDualView( this );
+    mDualView->setView( mViewMode );
+    connect( mDualView, &QgsDualView::showContextMenuExternally, this, &QgsRelationEditorWidget::showContextMenu );
+    mRelationLayout->addWidget( mDualView );
+  }
+
   QgsAttributeEditorContext ctx { mEditorContext };
   ctx.setParentFormFeature( mFeature );
   mDualView->init( layer, mEditorContext.mapCanvas(), request, ctx );
@@ -369,8 +370,11 @@ void QgsRelationEditorWidget::onCollapsedStateChanged( bool collapsed )
 {
   if ( !collapsed )
   {
-    mVisible = true;
-    updateUi();
+    if ( !mVisible )
+    {
+      mVisible = true;
+      updateUi();
+    }
   }
 }
 
@@ -379,17 +383,14 @@ void QgsRelationEditorWidget::updateUi()
   // If not yet initialized, it is not (yet) visible, so we don't load it to be faster (lazy loading)
   // If it is already initialized, it has been set visible before and the currently shown feature is changing
   // and the widget needs updating
-
-  if ( mVisible )
+  if ( mVisible && mRelation.isValid() && mFeature.isValid() )
   {
-    QgsFeatureRequest myRequest = mRelation.getRelatedFeaturesRequest( mFeature );
+    QgsFeatureRequest request = mRelation.getRelatedFeaturesRequest( mFeature );
 
     if ( mNmRelation.isValid() )
     {
-      QgsFeatureIterator it = mRelation.referencingLayer()->getFeatures( myRequest );
-
+      QgsFeatureIterator it = mRelation.referencingLayer()->getFeatures( request );
       QgsFeature fet;
-
       QStringList filters;
 
       while ( it.nextFeature( fet ) )
@@ -399,14 +400,13 @@ void QgsRelationEditorWidget::updateUi()
       }
 
       QgsFeatureRequest nmRequest;
-
       nmRequest.setFilterExpression( filters.join( QLatin1String( " OR " ) ) );
 
       initDualView( mNmRelation.referencedLayer(), nmRequest );
     }
     else if ( mRelation.referencingLayer() )
     {
-      initDualView( mRelation.referencingLayer(), myRequest );
+      initDualView( mRelation.referencingLayer(), request );
     }
   }
 }