QDialog modeless problem

[caduel]

either just do not delete it but just let it become hidden (no problem at all; it will just use a bit of memory...)

or

store the pointer to the dialog in a QPointer (always a good idea!) so you get "notified" (well, not you, but the QPointer) about the demise of the dialog and you do not end up with an invalid dangling pointer.

HTH