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Thread: Event Issues

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    Default Event Issues

    I'm writing a program (or should I say, I have written a program) that generates orbits from an Iterative Function System... but it has no GUI. Well, after a few months I've grown weary of that, so I decided to switch to netbeans and toss up a little GUI (window builder for eclipse... dreadful). The problem is, I need the JFrame (or a table component therein) to listen for an event. From a class that isn't event driven. I used to send a few lines of information per percent of completion, which I would like to land in the table component [that part I've figured out], and update that table every percent or tenth of a percent. Something like:

    IFS: "Hey! Another percent of 80 million points complete... could you let that fractal dude know?
    JFrame: Sure!

    I know I'll have to add an event listener to the component, and that I may have to write an event (I'd rather not if its avoidable). Concisely my query is how to fire off the event in a class with no GUI and have the JFrame.component 'hear' it.


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    Super Moderator Norm's Avatar
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    Default Re: Event Issues

    how to fire off the event in a class with no GUI and have the JFrame.component 'hear' it
    You could have the other class call a method in the GUI class when you want it to know of the event.
    To make it "type safe" you could define an interface containing the method to be called and the type of data to be passed and have the GUI class implement that interface. The method being called in the GUI class should act like any good listener, make a note of the event, copy needed data and return very quickly to the caller.

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

    fractalorbit (September 2nd, 2011)

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    Default Re: Event Issues

    Thank you very much! That helps a lot. I'm not trying to plug myself here, but I have a lot of the output of my program here. Not that its pertinent to the problem (why I didn't have it in the initial post) but it may be interesting to someone The Fractal Rant. Though, it seems like with that approach I might not need to use an actual event. Am I mistaken? By calling the method in the GUI class, passing it a parameter that contains all the updated information, could I not reflect the update on the GUI without using the event system?

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    Super Moderator Norm's Avatar
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    Default Re: Event Issues

    Your call would be very similar to the GUI class being called at one of its listener methods.

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