ViewManager: fix crash on view close

View widgets connect 'destroyed()' signal to a lambda which removes them
from the list.
This causes iterator removal while on close we loop all the lists and
delete views.
To fix that, empty the list and loop on copies

src/viewmanager/viewmanager.cpp

@@ -259,21 +259,7 @@ void ViewManager::onJobRemoved(db_id jobId)
     //If jobId is zero, it means all jobs have been deleted
     //Reload all views, Shift Graph Editor already reloads itself
 
-    //Close all rollingstock views because we have no couplings anymore
-    qDeleteAll(rsHash);
-    rsHash.clear();
-
-    //Close all station job view
-    qDeleteAll(stHash);
-    stHash.clear();
-
-    //Close all station free RS view
-    qDeleteAll(stRSHash);
-    stRSHash.clear();
-
-    //Close any shift job view
-    qDeleteAll(shiftHash);
-    shiftHash.clear();
+    closeJobRelatedViewsHelper();
 
     //Reload station plans
     for(auto st : qAsConst(stPlanHash))
@@ -502,6 +488,32 @@ ShiftViewer* ViewManager::createShiftViewer(db_id id)
     return viewer;
 }
 
+void ViewManager::closeJobRelatedViewsHelper()
+{
+    //Close all Job related views except managers and Shift Graph Editor
+    //SVG station plans are left open because they are useful also for other purposes
+
+    //NOTE: because views destroyed() signals are connected to lambda
+    //which remove them from the list, they invalidate iterators.
+    //To avoid this we copy the list (swap) and iterate from copy
+
+    //Close all rollingstock views because we have no couplings anymore
+    auto rsHashCopy = std::move(rsHash);
+    qDeleteAll(rsHashCopy);
+
+    //Close all station job view
+    auto stHashCopy = std::move(stHash);
+    qDeleteAll(stHashCopy);
+
+    //Close all station free RS view
+    auto stRSHashCopy = std::move(stRSHash);
+    qDeleteAll(stRSHashCopy);
+
+    //Close any shift job view
+    auto shiftHashCopy = std::move(shiftHash);
+    qDeleteAll(shiftHashCopy);
+}
+
 void ViewManager::requestShiftViewer(db_id id)
 {
     ShiftViewer *viewer = nullptr;
@@ -571,29 +583,23 @@ bool ViewManager::closeEditors()
         return false;
     }
 
-    qDeleteAll(rsHash);
-    rsHash.clear();
-
     if(stManager && !stManager->close())
     {
         return false;
     }
 
-    qDeleteAll(stHash);
-    stHash.clear();
-
-    qDeleteAll(stRSHash);
-    stRSHash.clear();
-
-    qDeleteAll(stPlanHash);
-    stPlanHash.clear();
-
-
     if(shiftManager && !shiftManager->close())
     {
         return false;
     }
 
+    closeJobRelatedViewsHelper();
+
+    //Also close SVG Station Plans now
+    //NOTE: use copy to avoid using invalid iterators, see closeJobRelatedViewsHelper()
+    auto stPlanCopy = std::move(stPlanHash);
+    qDeleteAll(stPlanCopy);
+
     if(shiftGraphEditor)
     {
         //Delete immidiately so ShiftGraphHolder gets deleted and releases queries
@@ -602,9 +608,6 @@ bool ViewManager::closeEditors()
         shiftGraphEditor = nullptr;
     }
 
-    qDeleteAll(shiftHash);
-    shiftHash.clear();
-
     return true;
 }
 

src/viewmanager/viewmanager.h

@@ -101,6 +101,8 @@ private:
     StationFreeRSViewer *createStFreeRSViewer(db_id stId);
     ShiftViewer *createShiftViewer(db_id id);
 
+    void closeJobRelatedViewsHelper();
+
 private:
     LineGraphManager *lineGraphManager;