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Thread: Best way to acces MainWindow instance from separate class

  1. #1
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    Default Best way to acces MainWindow instance from separate class

    Hello,

    What is the best way to access MainWindow instance from a separate class.

    Main.cpp
    Qt Code:
    1. ...
    2. int main(int argc, char *argv[])
    3. {
    4. QApplication a(argc, argv);
    5. MainWindow w;
    6. w.show();
    7.  
    8. return a.exec();
    9. }
    10. ...
    To copy to clipboard, switch view to plain text mode 

    How can I do this?

    Thank you have a good day!

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    Default Re: Best way to acces MainWindow instance from separate class

    Pass a pointer to the window instance to the other class instance or use signals and slots.
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    Default Re: Best way to acces MainWindow instance from separate class

    Quote Originally Posted by wysota View Post
    Pass a pointer to the window instance to the other class instance or use signals and slots.
    Hello,

    How can you use signals and slots to accomplish this?

    Thank you

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    Default Re: Best way to acces MainWindow instance from separate class

    You connect signals from the window instance to the other object and vice-versa. All depending on what functionality you want to implement.
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    Default Re: Best way to acces MainWindow instance from separate class

    MainWindow class contains a QTableWidget, I am trying to access the tables data from another class. It has to be accessing the current instance of the class.

    Thank you

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    Default Re: Best way to acces MainWindow instance from separate class

    The answer hasn't changed.

    You use generic C++ mechanisms to achieve this. Expose the data through a public interface and give the other class instance a pointer/reference to the source instance.
    OR
    When something happens in the table widget that the other class needs to hear about you emit a signal which is, in turn, connected to a slot in the other class. The signal can carry relevant data as parameters.

    If the entire content of the QTableWidget needs to be shared between views then you should be using QTableView and a separate shared model.

    Exactly how you do it is strongly dependent on what you need to achieve.

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    Default Re: Best way to acces MainWindow instance from separate class

    Thank you I understand now.

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