remove on primary docks on special cases

--primary docks are removed when their edge is
occupied in the new primary screen and their
current screen is destroyed. Also they are added
when the screen edge is available

app/dockcorona.cpp

@@ -311,8 +311,10 @@ void DockCorona::syncDockViews()
             }
 
             bool onPrimary = cont->config().readEntry("onPrimary", true);
+            Plasma::Types::Location location = (Plasma::Types::Location)((int)cont->config().readEntry("location", (int)Plasma::Types::BottomEdge));
 
-            if ((onPrimary || (m_screenPool->connector(id) == scr->name())) && (!m_dockViews.contains(cont))) {
+            if (( (onPrimary && freeEdges(qGuiApp->primaryScreen()).contains(location)) || (m_screenPool->connector(id) == scr->name()))
+                    && (!m_dockViews.contains(cont))) {
                 qDebug() << "screen Count signal: view must be added... for:" << scr->name();
                 addDock(cont);
             }
@@ -359,12 +361,6 @@ void DockCorona::syncDockViews()
         bool found{false};
 
         foreach (auto scr, qGuiApp->screens()) {
-            int id = view->containment()->screen();
-
-            if (id == -1) {
-                id = view->containment()->lastScreen();
-            }
-
             if (scr->name() == view->currentScreen()) {
                 found = true;
                 break;
@@ -379,6 +375,11 @@ void DockCorona::syncDockViews()
                 auto viewToDelete = m_dockViews.take(view->containment());
                 viewToDelete->deleteLater();
             }
+        } else if (view->onPrimary() && !found
+                   && !freeEdges(qGuiApp->primaryScreen()).contains(view->location())){
+            qDebug() << "screen Count signal: primary view must be deleted... for:" << view->currentScreen();
+            auto viewToDelete = m_dockViews.take(view->containment());
+            viewToDelete->deleteLater();
         } else {
             view->reconsiderScreen();
         }

shell/contents/configuration/BehaviorConfig.qml

@@ -130,12 +130,8 @@ PlasmaComponents.Page {
                         if (index === 0) {
                             var succeed = dock.setCurrentScreen("primary");
 
-                            if (succeed) {
-                                dock.onPrimary = true;
-                            } else {
-                                console.log("the edge is already occupied!!!");
-                                acceptedIndex = false;
-                            }
+                            dock.onPrimary = true;
+                            acceptedIndex = true;
                         } else if (index>0 && (index !== find(dock.currentScreen) || dock.onPrimary)) {
                             console.log("current index changed!!! :"+ index);
                             console.log("screen must be changed...");