diff --git a/sources/diagramview.cpp b/sources/diagramview.cpp
index 48242462a..d1dbc6b18 100644
--- a/sources/diagramview.cpp
+++ b/sources/diagramview.cpp
@@ -101,7 +101,6 @@ DiagramView::DiagramView(Diagram *diagram, QWidget *parent) :
 	}
 
 	connect(m_diagram, SIGNAL(showDiagram(Diagram*)), this, SIGNAL(showDiagram(Diagram*)));
-	connect(m_diagram, SIGNAL(selectionChanged()), this, SIGNAL(selectionChanged()));
 	connect(m_diagram, SIGNAL(sceneRectChanged(QRectF)), this, SLOT(adjustSceneRect()));
 	connect(&(m_diagram -> border_and_titleblock), SIGNAL(diagramTitleChanged(const QString &)), this, SLOT(updateWindowTitle()));
 	connect(diagram, SIGNAL(editElementRequired(ElementsLocation)), this, SIGNAL(editElementRequired(ElementsLocation)));
diff --git a/sources/diagramview.h b/sources/diagramview.h
index 9425dd439..d97b13b53 100644
--- a/sources/diagramview.h
+++ b/sources/diagramview.h
@@ -1,4 +1,4 @@
-/*
+/*
 	Copyright 2006-2019 The QElectroTech Team
 	This file is part of QElectroTech.
 	
@@ -102,8 +102,6 @@ class DiagramView : public QGraphicsView
 		bool gestures() const;
 
 	signals:
-			/// Signal emitted after the selection changed
-		void selectionChanged();
 			/// Signal emitted after the selection mode changed
 		void modeChanged();
 			/// Signal emitted after the diagram title changed
diff --git a/sources/projectview.cpp b/sources/projectview.cpp
index c74520e2a..422704795 100644
--- a/sources/projectview.cpp
+++ b/sources/projectview.cpp
@@ -56,11 +56,8 @@ ProjectView::ProjectView(QETProject *project, QWidget *parent) :
 	Supprime les DiagramView embarquees
 */
 ProjectView::~ProjectView() {
-	// qDebug() << "Suppression du ProjectView" << ((void *)this);
-	foreach(int id, m_diagram_ids.keys()) {
-		DiagramView *diagram_view = m_diagram_ids.take(id);
-		delete diagram_view;
-	}
+	for (auto dv_ : m_diagram_ids.values())
+		dv_->deleteLater();
 }
 
 /**
diff --git a/sources/qetdiagrameditor.cpp b/sources/qetdiagrameditor.cpp
index d85cedffa..9d26a479d 100644
--- a/sources/qetdiagrameditor.cpp
+++ b/sources/qetdiagrameditor.cpp
@@ -1932,17 +1932,26 @@ void QETDiagramEditor::activateProject(ProjectView *project_view) {
 }
 
 /**
-	Gere la fermeture d'une ProjectView
-	@param project_view ProjectView fermee
-*/
-void QETDiagramEditor::projectWasClosed(ProjectView *project_view) {
+ * @brief QETDiagramEditor::projectWasClosed
+ * Manage the close of a project.
+ * @param project_view
+ */
+void QETDiagramEditor::projectWasClosed(ProjectView *project_view)
+{
 	QETProject *project = project_view -> project();
-	if (project) {
+	if (project)
+	{
 		pa -> elementsPanel().projectWasClosed(project);
 		m_element_collection_widget->removeProject(project);
 		undo_group.removeStack(project -> undoStack());
 		QETApp::unregisterProject(project);
 	}
+
+		//When project is closed, a lot of signal are emited, notably if there is an item selected in a diagram.
+		//In some special case, since signal/slot connection can be direct or queued, some signal are handled after QObject is deleted, and crash qet
+		//notably in the function Diagram::elements when she call items() (I don't know exactly why).
+		//set nullptr to "m_selection_properties_editor->setDiagram()" fix this crash
+	m_selection_properties_editor->setDiagram(nullptr);
 	project_view -> deleteLater();
 	project -> deleteLater();
 }
@@ -2147,7 +2156,7 @@ void QETDiagramEditor::removeDiagramFromProject() {
  */
 void QETDiagramEditor::diagramWasAdded(DiagramView *dv)
 {
-	connect(dv, SIGNAL(selectionChanged()), this, SLOT(selectionChanged()));
+	connect(dv->diagram(), &QGraphicsScene::selectionChanged, this, &QETDiagramEditor::selectionChanged, Qt::DirectConnection);
 	connect(dv, SIGNAL(modeChanged()),      this, SLOT(slot_updateModeActions()));
 }