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I have a program that is basically set up just like the one in this MVC example: http://www.leepoint.net/notes-java/GUI/structure/40mvc.html

In my program there is a process which takes quite a bit of time which freezes my GUI. I want to GUI to continuously update while the process is running. To do this I believe I need to use a SwingWorker. I don't know where in my MVC pattern I should be invoking this SwingWorker.

My thinking is that I should be running it in the MultiplyListener actionlistener of the controller. Would this be correct?

Peck3277
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In this case, the model is a mathematical operation that evolves over time, perhaps by iteration. Clearly, the worker belongs in the model, as shown here. The setProgress() method will notify any PropertyChangeListener, and process() can notify any other listening view, as shown here.

Addendum: In the second example, the worker updates a different model: the chart's dataset named collection. The chart, in turn, listens to the dataset and updates itself in response to the change.

In the example cited, the controller installs action listeners on behalf of the model and view. In this related example, the GUI action listeners are local to their respective views. In either case, Action would be a suitable choice for encapsulation. The model notifies its observers when its internal state changes in response to user initiated actions.

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trashgod
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  • The [example cited](http://www.leepoint.net/notes-java/GUI/structure/40mvc.html) seems more traditional, while Swing is more _model_-centric. Conceptually, I think of the user as the GUI controller. – trashgod Mar 25 '13 at 21:37
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I think that your SwingWorker belongs in the Control and I'll tell you why. I feel that the Model should be as View agnostic as possible and should be created with the idea that it can be used with different views and controls, and even with a completely different GUI library, if desired. For instance, you are currently wanting to use the Model in a Swing GUI, but what if later you want to use it in an Android application? In order to allow it to be used with as few modifications as possible, most code that is Swing-specific, such as a SwingWorker should reside in the Control or View.

For example, please check out this answer.

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Hovercraft Full Of Eels
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  • I agree that the model should be as view agnostic as possible. I'm curious though--would you offer the same advice of using the controller for encapsulating the long-running process if that process were not specifically a `SwingWorker`, but were instead inheriting from `Thread`? My understanding was that `SwingWorker` was a convenience class very tightly integrated with `Swing`. If he were instead building such a construct himself which weren't so tightly integrated with `Swing` specifically, he might consider storing it elsewhere (the model), right? – nairware Jul 23 '13 at 21:28