Passing data between MainWindow and my class

[d_stranz]

So where does your instance of the CTester class live? Have you even declared an instance of it anywhere? If you haven't declared an instance of it, then how do you expect to call its Get and Set methods from any other class at all?

There is no magic to mixing pure C++ and Qt classes; the Qt libraries -are- C++ and the macros (like Q_OBJECT) are just aids to paste a lot of boilerplate code into header files and elsewhere. Signals and slots are just ordinary C++ methods and are called from within the Qt framework just like any other C++ method.

Of course, you have to have an instance of a class first before you can call any of its non-static members. Where do you want your instance of CTester to live?

[r2com]

I declared instance of CTester inside private section of QMainWindow:

private:
    Ui::MainWindow *ui;
    CTester aa;

private:
    Ui::MainWindow *ui;
    CTester aa;

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Then on the form designer I right click on the Get button and choose "GoTo SLot->clicked()" and enter this code:

void MainWindow::on_param1Get_clicked()
{
    aa.GetParam1();
    QString s = QString::number(aa.GetParam1());
    ui->param1Label->setText(s);
}

void MainWindow::on_param1Get_clicked()
{
    aa.GetParam1();
    QString s = QString::number(aa.GetParam1());
    ui->param1Label->setText(s);
}

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It does give me a LNK2019 error on compile.
And also, I have a feeling that I'm trying to achieve this in an ugly way and there gotta be an elegant solution.

[d_stranz]

LNK2019

And what else does it say besides "LNK2019"? Probably something about can't find a CTester constructor or a CTester:: GetParam() method, right? So did you add "Tester.cpp" or whatever you called the source file to the project? Did you add the paths to and names of your Qt library ".lib" files to the link properties? (Qt5Core, Qt5Gui, and Qt5Widgets, at a minimum for a GUI project).

By the way, you -do- realize that the code in your line 3 does nothing, right? Gets the parameter value, doesn't assign it to anything, then throws it away once the statment is done.

[anda_skoa]

And also, I have a feeling that I'm trying to achieve this in an ugly way and there gotta be an elegant solution.

Aside from the linker error and the unnecessary line that d_stranz mentioned this looks fine.

Cheers,
_