Linker Errors always after instantiation

[Machsanity]

Hey all,

I'm getting very frustrated with QT and I would like some advice on this. Every time I instantiate a new class within QT I will get linker errors without fail even I it is correctly instantiated. Now if I close the project and copy and paste everything into a fresh project, the linker error is gone and it works as it should. I have to copy and paste everything into a new project every time I want to do this. Any thoughts on how to fix this?

-Thanks

[Machsanity]

To be more specific the error is a LNK2019

[SGaist]

Hi and welcome to devnet,

You don't give enough information: what exact class are you using that gets you this error ? Did you check what module it's in ? Did you add the module to your pro file ?

e.g. using QSqlDatabase requires the sql module so your have to add QT += sql to your pro file and re-run qmake before you can use them

[Machsanity]

@SGaist

For example:

class A{
//constructor and functions here
}

class B{
// a.h included here
A *name = new A();

}

every time that format will throw a linker error. Say both of those are my own custom classes.

[SGaist]

Do I read right that you are including a header inside a class definition ?