Set the confirm of quit

Sources/GuiTools/WindowsManager/WindowsManager.cpp

@@ -153,5 +153,31 @@ void WindowsManager::OnMessage(int32_t id, int32_t dataID)
 				gtk_widget_destroy(dialog); // implicitly hides dialog
 			}
 			break;
+		case EDN_MSG__GUI_SHOW_ABOUT:
+			{
+				// dlg to confirm the quit event : 
+				GtkWidget *p_dialog = gtk_dialog_new_with_buttons("About",
+				                                                  NULL,
+				                                                  GTK_DIALOG_MODAL,
+				                                                  GTK_STOCK_YES, GTK_RESPONSE_YES,
+				                                                  GTK_STOCK_NO, GTK_RESPONSE_NO,
+				                                                  NULL);
+				GtkWidget *p_label =  gtk_label_new ("Do you want exit Edn?");
+				gtk_box_pack_start(GTK_BOX(gtk_dialog_get_content_area( GTK_DIALOG(p_dialog) )), p_label, TRUE, TRUE, 0);
+				
+				gtk_widget_show(p_label);
+				int32_t result = gtk_dialog_run (GTK_DIALOG (p_dialog));
+				gtk_widget_destroy(p_dialog);
+				switch (result)
+				{
+					case GTK_RESPONSE_YES:
+						gtk_main_quit();
+						break;
+					case GTK_RESPONSE_NO:
+						break;
+				}
+			}
+			break;
+			
 	}
 }