#14903: Avoid duplicate dock window ids for copied plots

Copies and plots created from templates kept the source DockWindowId. The dock
manager identifies dock widgets by name, so the earlier dock widget was deleted on
dock state restore, leaving a dangling pointer that crashed in setActiveViewer.

- Do not copy DockWindowId; copies get a new id
- Assign a new id if a dock widget with the same name exists
- Use QPointer for the dock widget

ApplicationLibCode/ProjectDataModel/RimDockWindowController.cpp

@@ -145,6 +145,14 @@ void RimDockWindowController::updateViewerWidget()
                 return;
             }
 
+            // The dock manager identifies dock widgets by name. A duplicate name (e.g. from a project saved with
+            // copied views) would unregister the existing dock widget, which is then deleted on next dock state restore.
+            if ( auto existing = mainWindow->dockManager()->findDockWidget( viewPdmObject()->dockWindowName() );
+                 existing && existing != dockWidget )
+            {
+                viewPdmObject()->resetDockWindowId();
+            }
+
             dockWidget->setWidget( viewWidget );
             dockWidget->setObjectName( viewPdmObject()->dockWindowName() );
             viewWidget->setObjectName( viewPdmObject()->dockWindowName() );

ApplicationLibCode/ProjectDataModel/RimMultiPlot.cpp

@@ -34,6 +34,8 @@
 #include "cafPdmUiComboBoxEditor.h"
 #include "cafPdmUiToolButtonEditor.h"
 
+#include "DockWidget.h"
+
 #include <QPaintDevice>
 #include <QRegularExpression>
 

ApplicationLibCode/ProjectDataModel/RimViewWindow.cpp

@@ -60,6 +60,9 @@ RimViewWindow::RimViewWindow()
 
     CAF_PDM_InitField( &m_dockWindowId, "DockWindowId", QString(), "Dock Window Id" );
     m_dockWindowId.uiCapability()->setUiHidden( true );
+    // The dock id must be unique, as the dock manager identifies dock widgets by name. Copies (including plots created
+    // from templates) get a new id.
+    m_dockWindowId.xmlCapability()->setCopyable( false );
 }
 
 //--------------------------------------------------------------------------------------------------

ApplicationLibCode/ProjectDataModel/RimViewWindow.h

@@ -25,6 +25,8 @@
 #include "cafPdmField.h"
 #include "cafPdmObject.h"
 
+#include <QPointer>
+
 class QImage;
 class RimDockWindowController;
 
@@ -117,8 +119,8 @@ private:
 protected:
     caf::PdmChildField<RimDockWindowController*> m_windowController;
 
-    caf::PdmField<bool>    m_showWindow;
-    ads::CDockWidget*      m_dockWidget;
-    caf::PdmField<QString> m_dockWindowId;
-    bool                   m_isActiveViewer;
+    caf::PdmField<bool>        m_showWindow;
+    QPointer<ads::CDockWidget> m_dockWidget;
+    caf::PdmField<QString>     m_dockWindowId;
+    bool                       m_isActiveViewer;
 };