8fcab70408
Change childWidget->windowHandle() to childWidget->internalWinId() in q_createNativeChildrenAndSetParent() to determine whether should we call childWidget->winId(). This is because in some circumstances Qt will crash due to accessing deleted QWidgetWindow object if we use windowHandle(). Think about the following scenario: 1) create a widget A without parent and add two child widgets B and C to A 2) create a native widget D as the child of B, note that when we set Qt::WA_NativeWindow attribute to it, its QWidgetWindow will be created which means its windowHandle() is not null. 3) create a top level widget E as the child of C and show it. This will make Qt call createWinId() to A and then q_createNativeChildrenAndSetParent() will be called to create A's native children recursively and finally make D's QWidgetWindow object become a child of A's QWidgetWindow object. Please note here that B will not become a native widget just because at that moment windowHandle() of D is not null and Qt will not call winId() to its parent B 4) Set A's parent to another widget which has been shown, setParent_sys() will be called to A and then Qt will call destroy() to A. in destroy() Qt will try to call destroy() to its children recursively with a condition that the child has Qt::WA_NativeWindow been set. But D's parent B is not a native widget right now so B and D is not destroyed. Qt will then deleted the QWidgetWindow object of A, since E's QWidgetWindow object is a child of A's QWidgetWindow object, it will also be deleted. Now E hold a deleted pointer of QWidgetWindow object. This is the source of crash later. Task-number: QTBUG-35600 Change-Id: I97a20a68e626ee62b15bb4eae580e26f8948923b Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com> Reviewed-by: Jørgen Lind <jorgen.lind@digia.com> |
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| .. | ||
| .gitignore | ||
| qwidget_window.pro | ||
| tst_qwidget_window.cpp | ||