[TD]improve handling of View in multiple Pages

src/Mod/TechDraw/App/DrawProjGroupItem.cpp

@@ -349,6 +349,38 @@ void DrawProjGroupItem::unsetupObject()
     DrawViewPart::unsetupObject();
 }
 
+//DPGIs have DPG as parent, not Page, so we need to ask the DPG how many Pages own it.
+int DrawProjGroupItem::countParentPages() const
+{
+    DrawProjGroup* dpg = getPGroup();
+    if (dpg != nullptr) {
+        int count = dpg->countParentPages();
+        return count;
+    }
+    return 0;
+}
+
+DrawPage* DrawProjGroupItem::findParentPage() const
+{
+    DrawProjGroup* dpg = getPGroup();
+    if (dpg != nullptr) {
+        DrawPage* dp = dpg->findParentPage();
+        return dp;
+    }
+    return nullptr;
+}
+
+std::vector<DrawPage*> DrawProjGroupItem::findAllParentPages() const
+{
+    DrawProjGroup* dpg = getPGroup();
+    if (dpg != nullptr) {
+        std::vector<DrawPage*> dps = dpg->findAllParentPages();
+        return dps;
+    }
+    std::vector<DrawPage*> empty;
+    return empty;
+}
+
 PyObject *DrawProjGroupItem::getPyObject(void)
 {
     if (PythonObject.is(Py::_None())) {

src/Mod/TechDraw/App/DrawProjGroupItem.h

@@ -89,6 +89,10 @@ public:
     virtual bool checkFit(void) const override { return true; }
     virtual bool checkFit(DrawPage*) const override { return true; }
 
+    virtual int countParentPages() const override;
+    virtual DrawPage* findParentPage() const override;
+    virtual std::vector<DrawPage*> findAllParentPages() const override;
+
 protected:
     void onChanged(const App::Property* prop) override;
     virtual bool isLocked(void) const override;

src/Mod/TechDraw/App/DrawView.cpp

@@ -246,6 +246,7 @@ void DrawView::onDocumentRestored()
  * in case it is also a child of another duplicate page
  * @return
  */
+//note this won't find parent pages for DrawProjItem since their parent is DrawProjGroup!
 int DrawView::countParentPages() const
 {
     int count = 0;
@@ -260,6 +261,9 @@ int DrawView::countParentPages() const
     return count;
 }
 
+//finds the first DrawPage in this Document that claims to own this DrawView
+//note that it is possible to manipulate the Views property of DrawPage so that
+//more than 1 DrawPage claims a DrawView.
 DrawPage* DrawView::findParentPage() const
 {
     // Get Feature Page
@@ -283,6 +287,33 @@ DrawPage* DrawView::findParentPage() const
     return page;
 }
 
+
+std::vector<DrawPage*> DrawView::findAllParentPages() const
+{
+    // Get Feature Page
+    std::vector<DrawPage*> result;
+    DrawPage *page = 0;
+    DrawViewCollection *collection = 0;
+    std::vector<App::DocumentObject*> parent = getInList();
+    for (std::vector<App::DocumentObject*>::iterator it = parent.begin(); it != parent.end(); ++it) {
+        if ((*it)->getTypeId().isDerivedFrom(DrawPage::getClassTypeId())) {
+            page = static_cast<TechDraw::DrawPage *>(*it);
+        }
+
+        if ((*it)->getTypeId().isDerivedFrom(DrawViewCollection::getClassTypeId())) {
+            collection = static_cast<TechDraw::DrawViewCollection *>(*it);
+            page = collection->findParentPage();
+        }
+
+        if(page) {
+            result.emplace_back(page);
+        }
+    }
+
+    return result;
+}
+
+
 bool DrawView::isInClip()
 {
     std::vector<App::DocumentObject*> parent = getInList();

src/Mod/TechDraw/App/DrawView.h

@@ -23,6 +23,8 @@
 #ifndef _DrawView_h_
 #define _DrawView_h_
 
+#include <Mod/TechDraw/TechDrawGlobal.h>
+
 #include <boost_signals2.hpp>
 
 #include <QCoreApplication>
@@ -85,6 +87,7 @@ public:
     virtual PyObject *getPyObject(void) override;
 
     virtual DrawPage* findParentPage() const;
+    virtual std::vector<DrawPage*> findAllParentPages() const;
     virtual int countParentPages() const;
     virtual QRectF getRect() const;                      //must be overridden by derived class
     virtual double autoScale(void) const;