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Thread: Can someone please explain this code for me?

  1. #1
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    Default Can someone please explain this code for me?

    @Override
    public void keyPressed(KeyEvent e)
    {
    if (e.getKeyChar() == 'a' ){
    String myS = myField.getText();
    myLabel.setText(myS);
    myLabel2.setText(“”);
    }
    }



    Can someone explain to me what this code actually does
    I'm trying to figure out what it does.

    Thanks

    Grot
    Last edited by Grot; January 17th, 2013 at 08:44 AM. Reason: wrap up code


  2. #2
    Super Moderator Norm's Avatar
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    Default Re: Can someone please explain this code for me?

    Where did you get the code?
    When the method is called it makes a test of the contents of its arg and if the test is true it calls some methods.

    Read the API doc for the KeyEvent class and its method that is used to see what they do.

    (“”)
    I don't know what that is. It looks like definitions for a code pre-processing program.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: Can someone please explain this code for me?

    I got this code from a book but it didn't explain it, I edited it there so you can see it better
    Thanks for the help Norm! you're a legend!

  4. #4
    Super Moderator Norm's Avatar
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    Default Re: Can someone please explain this code for me?

    Now what I called pre-processor code has changed to slanting "s that aren't available on my keyboard.
    An empty String from my keyboard would look like: "" vs the “” in the posted code. I guess the pre-processor I mentioned is the one that formats the forum's replies.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: Can someone please explain this code for me?

    I think “” is supposed to be "".

    From when I see in this code is that
    if a key 'a' is pressed something happens
    and it creates a space.

    Am I right?

  6. #6
    Super Moderator Norm's Avatar
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    Default Re: Can someone please explain this code for me?

    if a key 'a' is pressed
    That is assuming there is a connection between key presses and the method. The code does not show there is any connection.

    it creates a space
    It calls a method (setText) with an arg of an empty String: "" (no space between the ""s). Read the API doc for the method to see what it does.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: Can someone please explain this code for me?

    Quote Originally Posted by Grot View Post
    I think “” is supposed to be "".

    From when I see in this code is that
    if a key 'a' is pressed something happens
    and it creates a space.

    Am I right?
    Yes, it's common to cut and paste from an e-book and it ends up as “”.
    The code looks like it comes from a GUI, where it's looking for a key press (the event) and then it changes the labels on the GUI from a text field.
    Which book is it from?

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    Default Re: Can someone please explain this code for me?

    What does the String myS = myField.getText(); do?

  9. #9
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    Default Re: Can someone please explain this code for me?

    It defines a String variable, calls a method and assigns what is returned by the method to the variable.

    Read the API doc for the method to see what is in the String that is returned.
    If you don't understand my answer, don't ignore it, ask a question.

  10. The Following User Says Thank You to Norm For This Useful Post:

    Grot (January 17th, 2013)

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    Default Re: Can someone please explain this code for me?

    ok thanks Norm.

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