Replace Q3PtrList in diagram dialog

[wawuwo]

Hi!

This is another piece for #748

[dsm]

Hi, can we use QList instead of std::vector for this refactoring.

[wawuwo]

@dsm hi! Is there a specific reason for it? QList and std::vector both array-based, Graph is a private member of diagram dialog and is not passed as argument to any of QT APIs

[dsm]

Just looking your modification and the line in diagramdialog.cpp Graphs.erase(std::next(Graphs.begin(), i));, I'm questioning QList has a remove method ? maybe QList usage just simplify something like that in codes. It's just advice. but std::vector is ok :)

[wawuwo]

Now I see what you mean

I agree std::vector's iterator-based API is a bit clumsy… and QList indeed does have a nice remove method 🤔

[dsm]

Btw I Quick test QList over std::vector some compiler error happend, I think QList wants to copy uniquie ptr somewhere I don't know where but unique ptr doesn't copyable just movable maybe we can use weak_ptr or shared_ptr instead of unique if there isn't spesific desicion.

[wawuwo]

I am more inclined to keep the std::vector for this one… It works nice and easy in all cases except of removing an element, and here is only one case of removing (plus I just like to stick with standard library facilities when possible). But anyway, thanks for the advice and attention to details

[ra3xdh]

Merged. I didn't find issues while testing this.