Program crashes (SIGSEGV)

[Voldemort]

I understand what you mean. But I have questions:

#ifdef qApp
#undef qApp
#endif
#define qApp static_cast<MyApp*>(QCoreApplication::instance())

#ifdef qApp
#undef qApp
#endif
#define qApp static_cast<MyApp*>(QCoreApplication::instance())

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1) Where do I have to put this part? Every file? Just in the class file? Somewhere else?

2) With that code I have to include some classes I use (the part above my main function in main.cpp)?

3) Do I have to instantiate the class in all files or just in the main function? Or does it work in another way?

4) Can I put the delete lines (now at the bottom of my main function in main.cpp) in the destructor of the class?