[TD]fix front view position in projection group (fix #19085)

src/Mod/TechDraw/Gui/TaskProjGroup.cpp

@@ -59,6 +59,7 @@
 #include "ViewProviderPage.h"
 #include "ViewProviderDrawingView.h"
 #include "ViewProviderProjGroupItem.h"
+#include "ViewProviderProjGroup.h"
 
 
 using namespace Gui;
@@ -276,6 +277,7 @@ void TaskProjGroup::viewToggled(bool toggle)
         else {
             // If toggle then we remove the view object and create a proj group instead.
             turnViewToProjGroup();
+            changed = true;
         }
     }
 
@@ -293,6 +295,10 @@ void TaskProjGroup::viewToggled(bool toggle)
     }
 
     if (changed) {
+        // necessary to prevent position problems
+        Gui::Document* activeGui = Gui::Application::Instance->getDocument(m_page->getDocument());
+        auto* vppg = static_cast<ViewProviderProjGroup*>(activeGui->getViewProvider(multiView));
+        vppg->regroupSubViews();
         if (view->ScaleType.isValue("Automatic")) {
             double scale = view->getScale();
             setFractionalScale(scale);
@@ -312,7 +318,6 @@ void TaskProjGroup::turnViewToProjGroup()
     Gui::Command::doCommand(Gui::Command::Gui, "App.activeDocument().%s.addView(App.activeDocument().%s)", view->findParentPage()->getNameInDocument(), multiViewName.c_str());
 
     auto* viewPart = static_cast<TechDraw::DrawViewPart*>(view);
-    m_page->removeView(viewPart);
 
     multiView = static_cast<TechDraw::DrawProjGroup*>(doc->getObject(multiViewName.c_str()));
     multiView->Source.setValues(viewPart->Source.getValues());
@@ -322,23 +327,24 @@ void TaskProjGroup::turnViewToProjGroup()
     multiView->Scale.setValue(viewPart->Scale.getValue());
     multiView->ScaleType.setValue(viewPart->ScaleType.getValue());
     multiView->ProjectionType.setValue(Preferences::projectionAngle());
+
+    multiView->addView(viewPart);
+    multiView->Anchor.setValue(viewPart);
+    multiView->Anchor.purgeTouched();
+
     viewPart->X.setValue(0.0);
     viewPart->Y.setValue(0.0);
     viewPart->ScaleType.setValue("Custom");
     viewPart->ScaleType.setStatus(App::Property::Hidden, true);
     viewPart->Scale.setStatus(App::Property::Hidden, true);
     viewPart->Label.setValue("Front");
-
-    multiView->addView(viewPart);
-    multiView->Anchor.setValue(view);
-    multiView->Anchor.purgeTouched();
-
     viewPart->LockPosition.setValue(true);
     viewPart->LockPosition.setStatus(App::Property::ReadOnly, true); //Front should stay locked.
     viewPart->LockPosition.purgeTouched();
 
     m_page->requestPaint();
     view = multiView;
+    m_page->removeView(viewPart);   // prevent multiple entries in tree
 
     updateUi();
 }

src/Mod/TechDraw/Gui/ViewProviderProjGroup.cpp

@@ -43,6 +43,9 @@
 #include <Mod/TechDraw/App/DrawViewSection.h>
 
 #include "TaskProjGroup.h"
+#include "QGIViewPart.h"
+#include "QGSPage.h"
+#include "ViewProviderPage.h"
 #include "ViewProviderProjGroup.h"
 
 using namespace TechDrawGui;
@@ -216,3 +219,25 @@ TechDraw::DrawProjGroup* ViewProviderProjGroup::getObject() const
 {
     return getViewObject();
 }
+
+
+//! gather the (existing) graphics for our sub views into our scene group.
+void ViewProviderProjGroup::regroupSubViews()
+{
+    auto vpPage = getViewProviderPage();
+    if (!vpPage) {
+        return;
+    }
+
+    auto scene = vpPage->getQGSPage();
+    auto dpgQView = getQView();
+
+    auto viewsAll =  getObject()->getViewsAsDPGI();
+    for (auto& view : viewsAll) {
+        auto viewQView = dynamic_cast<QGIViewPart *>(scene->findQViewForDocObj(view));
+        if (viewQView) {
+            scene->addItemToParent(viewQView, dpgQView);
+        }
+    }
+}
+

src/Mod/TechDraw/Gui/ViewProviderProjGroup.h

@@ -54,6 +54,8 @@ public:
     bool onDelete(const std::vector<std::string> &parms) override;
     bool canDelete(App::DocumentObject* obj) const override;
 
+    void regroupSubViews();
+
 protected:
     bool setEdit(int ModNum) override;