on destruction

GUI/View/PlotUtil/IntensityDataPropertyWidget.cpp

@@ -154,7 +154,7 @@ void IntensityDataPropertyWidget::setItem(QVector<IntensityDataItem*> itemsVec)
     this);
 #else
     FOR_EACH_ITEM
-            connect(item, &IntensityDataItem::axesUnitsChanged, this, [=]() {
+            connect(item, &IntensityDataItem::axesUnitsChanged, this, [=](){
                 if(jobItem()) {
                     item->blockSignals(true);
                     item->updateCoords(jobItem()->instrumentItem());
@@ -163,6 +163,16 @@ void IntensityDataPropertyWidget::setItem(QVector<IntensityDataItem*> itemsVec)
                 }
             });
 #endif
+
+    for(int i=0; i<itemsVec.size(); i++)
+        if(itemsVec[i])
+#ifdef USE_MAPPERS
+            itemsVec[i]->mapper()->setOnItemDestroy(
+                        [this, i](SessionItem*) { m_items_vec[i] = nullptr; }, this);
+#else
+            connect(itemsVec[i], &IntensityDataItem::destroyed, this,
+                    [=]() { m_items_vec[i] = nullptr; });
+#endif
 }
 
 const JobItem* IntensityDataPropertyWidget::jobItem() const