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Thread: a quetion about signals and slots

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    Question a quetion about signals and slots

    I started with signals and slots follwing the exercise at zetcode

    button.clicked.connect(self.onClicked)

    button = QGui.QPushButton()

    if button is the object created

    then what is clicked and connect

    from what i understand if clicked is an event that occurred, so is it method defined inside QPushButton ?

    what is connect then ?

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    Default Re: a quetion about signals and slots

    clicked will represent the signal. connect is a method to join a signal to a slot
    If you have a problem, CUT and PASTE your code. Do not retype or simplify it. Give a COMPLETE and COMPILABLE example of your problem. Otherwise we are all guessing the problem from a fabrication where relevant details are often missing.

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    Default Re: a quetion about signals and slots

    Quote Originally Posted by krystosan View Post
    from what i understand if clicked is an event that occurred, so is it method defined inside QPushButton ?
    As amleto already said, "clicked" is what Qt calls a signal. Your guess was already very good, you can think of it as a high level event that the button sends whenever it is clicked and your assumption that it is implemented in the button class is also correct (not in QPushButton though, but in QPushButton's base class QAbstractButton).


    Quote Originally Posted by krystosan View Post
    what is connect then ?
    Again as amleto said, it is a method to tell Qt which function you would like to get executed when the "clicked" signal/event happens.

    Cheers,
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    Default Re: a quetion about signals and slots

    so can i think of clicked method sort of pure virtual function of C++

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    Default Re: a quetion about signals and slots

    Quote Originally Posted by krystosan View Post
    so can i think of clicked method sort of pure virtual function of C++
    No, it's neither pure nor virtual. It's just a method declared in a class and implemented by a special tool called Meta-Object Compiler that is executed when Qt is built.
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