Desktop: destroy maintab before destructing mainwindow

Apparently, in some Qt-versions the destructor of the base class
calls hide on child-objects (according to Qt's object hierarchy).
This is obviously called after the derived class has been destructed.

In a concrete case, the base class of the destructed MainWindow
would hide the TabDiveSite object. That would reset the filtering
if a dive site was selected, which would indirectly access the
MainWindow, which is already partially destroyed.

Therefore, destroy the MainTab before destroying the MainWindow.
Do this by keeping it as a std::unique_ptr subobject. Thus, it
will be destroyed before the MainWindow and remove itself from
Qt's object hierarchy.

Reported-by: Dirk Hohndel <dirk@hohndel.org>
Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

1 files changed, 2 insertions, 1 deletions

diff --git a/desktop-widgets/mainwindow.h b/desktop-widgets/mainwindow.h
index efac8610e..252a95b98 100644
--- a/desktop-widgets/mainwindow.h
+++ b/desktop-widgets/mainwindow.h
@@ -13,6 +13,7 @@
 #include <QUrl>
 #include <QUuid>
 #include <QProgressDialog>
+#include <memory>
 
 #include "ui_mainwindow.h"
 #include "ui_plannerDetails.h"
@@ -84,7 +85,7 @@ public:
 	void exitEditState();
 	void editDiveSite(dive_site *ds);
 
-	MainTab *mainTab;
+	std::unique_ptr<MainTab> mainTab;
 	PlannerDetails *plannerDetails;
 	PlannerSettingsWidget *divePlannerSettingsWidget;
 	ProfileWidget2 *graphics;