calling parent class methods from an extended subclass


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Thread: calling parent class methods from an extended subclass

  1. #1
    Nate McFeters Guest

    calling parent class methods from an extended subclass


    Basically here is the gist of my problem: I've created a GUI thats a Calendar
    to store to do list items for each day of the month. My main class, myCalendar,contains
    a method called addItem. This method takes an object I've created(a to do
    list Item) and stores it into a Vector. Later I call a method called printUnsorted(
    from within the myCalendar class), which should access each element of the
    Vector and then output the element to the screen. I have a subclass called
    multiBox which extends from the myCalendar class. I extend it so that it
    can access myCalendar's addItem method. Basically this subclass is declared
    within myCalendar, then myCalendar sets it to visible after a day on the
    calendar has been double clicked. multiBox is a frame, just like myCalendar
    is. The user enters all the fields of an object( the to do list Item ) and
    then clicks done. When done is clicked, multiBox calls myCalendar's addItem
    with this new object as the passed in parameter. The problem here is this:
    When inside multiBox I do get this object. I can output it and everything.
    After I call addItem, and I'm inside addItem's body, the object is still
    there. Then I add it to the Vector. I can than still access that item in
    the Vector and output it to the screen so I know its still there, but when
    myCalendar calls the printUnsorted method, and then prints out the Vector,
    the Item is no longer there. In fact the Vector has a size of 0. I don't
    know if it is because of the multiple frames, or how I'm making multiBox
    a subclass of myCalendar, but I can't seem to get it to work. I would so
    appreciate any help, and I can even send you the code if need be.

    Thanks so much,
    Nate


  2. #2
    Chris Birkett Guest

    Re: calling parent class methods from an extended subclass


    It sounds strange that you said multiBox extends myCalendar which means it's
    a subclass, but you also said it's declared inside myCalendar which means
    it's an inner class. It probably shouldn't be both. However, I don't think
    this is causing the problem. I would have to see the code. printSorted()
    sounds like it might be using a local variable of type Vector which has the
    same name as the member variable of type Vector. That's just a problem that
    I have had.

    "Nate McFeters" <smoothnate@collegeclub.com> wrote:
    >
    >Basically here is the gist of my problem: I've created a GUI thats a Calendar
    >to store to do list items for each day of the month. My main class, myCalendar,contains
    >a method called addItem. This method takes an object I've created(a to

    do
    >list Item) and stores it into a Vector. Later I call a method called printUnsorted(
    >from within the myCalendar class), which should access each element of the
    >Vector and then output the element to the screen. I have a subclass called
    >multiBox which extends from the myCalendar class. I extend it so that it
    >can access myCalendar's addItem method. Basically this subclass is declared
    >within myCalendar, then myCalendar sets it to visible after a day on the
    >calendar has been double clicked. multiBox is a frame, just like myCalendar
    >is. The user enters all the fields of an object( the to do list Item )

    and
    >then clicks done. When done is clicked, multiBox calls myCalendar's addItem
    >with this new object as the passed in parameter. The problem here is this:
    > When inside multiBox I do get this object. I can output it and everything.
    > After I call addItem, and I'm inside addItem's body, the object is still
    >there. Then I add it to the Vector. I can than still access that item

    in
    >the Vector and output it to the screen so I know its still there, but when
    >myCalendar calls the printUnsorted method, and then prints out the Vector,
    >the Item is no longer there. In fact the Vector has a size of 0. I don't
    >know if it is because of the multiple frames, or how I'm making multiBox
    >a subclass of myCalendar, but I can't seem to get it to work. I would so
    >appreciate any help, and I can even send you the code if need be.
    >
    >Thanks so much,
    >Nate
    >



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