update display expression when adding fields through attribute table (#…

…46978) (fix #28353)
qgis · Jan 27, 2022 · 46307f7 · 46307f7
1 parent 80f2443
commit 46307f7
Showing 1 changed file with 10 additions and 1 deletion.
diff --git a/src/app/qgsattributetabledialog.cpp b/src/app/qgsattributetabledialog.cpp
@@ -890,14 +890,18 @@ void QgsAttributeTableDialog::mActionAddAttribute_triggered()
     if ( mLayer->addAttribute( dialog.field() ) )
     {
       mLayer->endEditCommand();
+
+      if ( mLayer->displayExpression().isEmpty() )
+      {
+        mLayer->setDisplayExpression( dialog.field().name() );
+      }
     }
     else
     {
       mLayer->destroyEditCommand();
       QMessageBox::critical( this, tr( "Add Field" ), tr( "Failed to add field '%1' of type '%2'. Is the field name unique?" ).arg( dialog.field().name(), dialog.field().typeName() ) );
     }
 
-
     // update model - a field has been added or updated
     masterModel->reload( masterModel->index( 0, 0 ), masterModel->index( masterModel->rowCount() - 1, masterModel->columnCount() - 1 ) );
   }
@@ -919,12 +923,17 @@ void QgsAttributeTableDialog::mActionRemoveAttribute_triggered()
       return;
     }
 
+    // check whether display expression is a single field
+    int fieldIdx = QgsExpression::expressionToLayerFieldIndex( mLayer->displayExpression(), mLayer );
     QgsAttributeTableModel *masterModel = mMainView->masterModel();
 
     mLayer->beginEditCommand( tr( "Deleted attribute" ) );
     if ( mLayer->deleteAttributes( attributes ) )
     {
       mLayer->endEditCommand();
+
+      if ( fieldIdx != -1 && attributes.contains( fieldIdx ) )
+        mLayer->setDisplayExpression( mLayer->fields().count() > 0 ? mLayer->fields().at( 0 ).name() : QString() );
     }
     else
     {