If the same item is reselected in a layout, don't create a new

properties widget for it

Because if we do annoying things happen, like loss of focused
widget and scroll bar position

python/gui/layout/qgslayoutitemwidget.sip

@@ -75,6 +75,12 @@ class QgsLayoutItemBaseWidget: QgsPanelWidget
  Constructor for QgsLayoutItemBaseWidget, linked with the specified ``layoutObject``.
 %End
 
+    QgsLayoutObject *layoutObject();
+%Docstring
+ Returns the layout object associated with this widget.
+ :rtype: QgsLayoutObject
+%End
+
   protected:
 
     void registerDataDefinedButton( QgsPropertyOverrideButton *button, QgsLayoutObject::DataDefinedProperty property );

src/app/layout/qgslayoutdesignerdialog.cpp

@@ -620,6 +620,18 @@ void QgsLayoutDesignerDialog::showItemOptions( QgsLayoutItem *item, bool bringPa
     return;
   }
 
+  if ( auto widget = qobject_cast< QgsLayoutItemBaseWidget * >( mItemPropertiesStack->mainPanel() ) )
+  {
+    if ( widget->layoutObject() == item )
+    {
+      // already showing properties for this item - we don't want to create a new panel
+      if ( bringPanelToFront )
+        mItemDock->setUserVisible( true );
+
+      return;
+    }
+  }
+
   std::unique_ptr< QgsLayoutItemBaseWidget > widget( QgsGui::layoutItemGuiRegistry()->createItemWidget( item ) );
   if ( ! widget )
   {
@@ -1069,8 +1081,8 @@ void QgsLayoutDesignerDialog::createLayoutPropertiesWidget()
   }
 
   // update layout based widgets
-  QgsLayoutPropertiesWidget *oldCompositionWidget = qobject_cast<QgsLayoutPropertiesWidget *>( mGeneralPropertiesStack->takeMainPanel() );
-  delete oldCompositionWidget;
+  QgsLayoutPropertiesWidget *oldLayoutWidget = qobject_cast<QgsLayoutPropertiesWidget *>( mGeneralPropertiesStack->takeMainPanel() );
+  delete oldLayoutWidget;
   QgsLayoutGuideWidget *oldGuideWidget = qobject_cast<QgsLayoutGuideWidget *>( mGuideStack->takeMainPanel() );
   delete oldGuideWidget;
 

src/gui/layout/qgslayoutitemwidget.cpp

@@ -129,10 +129,16 @@ QgsVectorLayer *QgsLayoutConfigObject::coverageLayer() const
 QgsLayoutItemBaseWidget::QgsLayoutItemBaseWidget( QWidget *parent, QgsLayoutObject *layoutObject )
   : QgsPanelWidget( parent )
   , mConfigObject( new QgsLayoutConfigObject( this, layoutObject ) )
+  , mObject( layoutObject )
 {
 
 }
 
+QgsLayoutObject *QgsLayoutItemBaseWidget::layoutObject()
+{
+  return mObject;
+}
+
 void QgsLayoutItemBaseWidget::registerDataDefinedButton( QgsPropertyOverrideButton *button, QgsLayoutObject::DataDefinedProperty property )
 {
   mConfigObject->initializeDataDefinedButton( button, property );
@@ -165,7 +171,7 @@ void QgsLayoutItemPropertiesWidget::updateVariables()
 {
   QgsExpressionContext context = mItem->createExpressionContext();
   mVariableEditor->setContext( &context );
-  int editableIndex = context.indexOfScope( tr( "Composer Item" ) );
+  int editableIndex = context.indexOfScope( tr( "Layout Item" ) );
   if ( editableIndex >= 0 )
     mVariableEditor->setEditableScopeIndex( editableIndex );
 }
@@ -212,7 +218,6 @@ QgsLayoutItemPropertiesWidget::QgsLayoutItemPropertiesWidget( QWidget *parent, Q
   mStrokeUnitsComboBox->linkToWidget( mStrokeWidthSpinBox );
   mStrokeUnitsComboBox->setConverter( &mItem->layout()->context().measurementConverter() );
 
-
   //make button exclusive
   QButtonGroup *buttonGroup = new QButtonGroup( this );
   buttonGroup->addButton( mUpperLeftCheckBox );

src/gui/layout/qgslayoutitemwidget.h

@@ -121,6 +121,11 @@ class GUI_EXPORT QgsLayoutItemBaseWidget: public QgsPanelWidget
      */
     QgsLayoutItemBaseWidget( QWidget *parent SIP_TRANSFERTHIS, QgsLayoutObject *layoutObject );
 
+    /**
+     * Returns the layout object associated with this widget.
+     */
+    QgsLayoutObject *layoutObject();
+
   protected:
 
     /**
@@ -147,6 +152,8 @@ class GUI_EXPORT QgsLayoutItemBaseWidget: public QgsPanelWidget
   private:
 
     QgsLayoutConfigObject *mConfigObject = nullptr;
+
+    QgsLayoutObject *mObject = nullptr;
 };