Method dropObject

src/Mod/TechDraw/Gui/ViewProviderPageExtension.cpp:124–196

this code used to live in ViewProviderPage

//this code used to live in ViewProviderPage
void ViewProviderPageExtension::dropObject(App::DocumentObject* obj)
{
    auto dvp = freecad_cast<TechDraw::DrawViewPart*>(obj);
    if (dvp && DrawView::isProjGroupItem(dvp)) {
        //DPGI can not be dropped onto the Page if it belongs to DPG
        auto* dpgi = static_cast<TechDraw::DrawProjGroupItem*>(obj);
        if (dpgi->getPGroup()) {
            return;
        }
    }
    if (obj->isDerivedFrom<App::Link>()) {
        auto* link = static_cast<App::Link*>(obj);
        obj = link->getLinkedObject();
        if (!obj->isDerivedFrom<TechDraw::DrawView>()) {
            return;
        }

        std::vector<App::DocumentObject*> deps;
        for (auto& inObj : obj->getInList()) {
            if (inObj && inObj->isDerivedFrom<TechDraw::DrawView>()) {
                deps.push_back(inObj);
            }
        }

        TechDraw::DrawPage* page = nullptr;
        for (auto& inObj : link->getInList()) {
            if (inObj->isDerivedFrom<TechDraw::DrawPage>()) {
                page = static_cast<TechDraw::DrawPage*>(inObj);
            }
        }
        if (page) {
            for (auto* dep : deps) {
                page->removeView(dep);
            }
            page->removeView(link);
        }

        getViewProviderPage()->getDrawPage()->addView(link, false);
        for (auto* dep : deps) {
            getViewProviderPage()->getDrawPage()->addView(dep, false);
        }

        return;
    }

    if (obj->isDerivedFrom<TechDraw::DrawView>()) {
        auto dv = static_cast<TechDraw::DrawView*>(obj);

        std::vector<App::DocumentObject*> deps;
        for (auto* dep : dv->getInList()) {
            if (dep && dep->isDerivedFrom<TechDraw::DrawView>()) {
                deps.push_back(dep);
            }
        }

        auto* parentPage = dv->findParentPage();
        if (parentPage) {
            for (auto* dep : deps) {