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Linker Errors always after instantiation

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  • M Offline
    M Offline
    Machsanity
    wrote on last edited by
    #1

    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

    M 1 Reply Last reply
    0
    • M 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

      M Offline
      M Offline
      Machsanity
      wrote on last edited by
      #2

      To be more specific the error is a LNK2019

      1 Reply Last reply
      0
      • SGaistS Offline
        SGaistS Offline
        SGaist
        Lifetime Qt Champion
        wrote on last edited by
        #3

        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

        Interested in AI ? www.idiap.ch
        Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

        M 1 Reply Last reply
        0
        • SGaistS 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

          M Offline
          M Offline
          Machsanity
          wrote on last edited by Machsanity
          #4

          @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.

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          • SGaistS Offline
            SGaistS Offline
            SGaist
            Lifetime Qt Champion
            wrote on last edited by
            #5

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

            Interested in AI ? www.idiap.ch
            Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

            1 Reply Last reply
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