[TD]handle AutoDistribute property toggle

src/Mod/TechDraw/Gui/ViewProviderProjGroup.cpp

@@ -43,6 +43,7 @@
 
 #include "TaskProjGroup.h"
 #include "QGIViewPart.h"
+#include "QGIProjGroup.h"
 #include "QGSPage.h"
 #include "ViewProviderPage.h"
 #include "ViewProviderProjGroup.h"
@@ -240,3 +241,33 @@ void ViewProviderProjGroup::regroupSubViews()
     }
 }
 
+void ViewProviderProjGroup::updateData(const App::Property* prop)
+{
+    TechDraw::DrawProjGroup* group = getViewObject();
+    if (prop == &group->AutoDistribute) {
+        onChangeAutoDistribute();
+        return;
+    }
+
+    ViewProviderDrawingView::updateData(prop);
+}
+
+void ViewProviderProjGroup::onChangeAutoDistribute()
+{
+    auto* groupQGI = static_cast<QGIProjGroup*>(getQView());
+    if (!groupQGI) {
+        // our QGItem does not exist yet
+        return;
+    }
+
+    QList<QGIViewPart*> secondaryQViews = groupQGI->secondaryQViews();
+    for (auto& secondary : secondaryQViews) {
+        if (secondary == groupQGI->getAnchorQItem()) {
+            // do not touch the anchor
+            continue;
+        }
+        secondary->updateView(false);
+    }
+}
+
+

src/Mod/TechDraw/Gui/ViewProviderProjGroup.h

@@ -55,6 +55,9 @@ public:
     bool canDelete(App::DocumentObject* obj) const override;
 
     void regroupSubViews();
+    void updateData(const App::Property* prop) override;
+    void onChangeAutoDistribute();
+
 
 protected:
     bool setEdit(int ModNum) override;