Question

I’ve got a Swing application with a model and a view. In the view (GUI) there are a lot of components, each of them mapping to some property of a model object and displaying it’s value.

Now there are some UI components that automatically trigger the updating of some model properties when their value changes in the UI. This requires me to reload the complete model in the UI. This way I’m entering an infinite update loop, as every model reload in the UI triggers another model reload.

I have a flag indicating the load process, which I’d like to use to temporarily suppress the listener notifications, while the UI fields are being set from the model. So my question is:

Is there a way to globally temporarily disable some component’s listeners in Swing without removing and reattaching them?

Answer 1

You could use a common base class for your listeners and in it, have a static method to turn the listeners on or off:

public abstract class BaseMouseListener implements ActionListener{

    private static boolean active = true;
    public static void setActive(boolean active){
        BaseMouseListener.active = active;
    }

    protected abstract void doPerformAction(ActionEvent e);

    @Override
    public final void actionPerformed(ActionEvent e){
        if(active){
            doPerformAction(e);
        }
    }
}

Your listeners would have to implement doPerformAction() instead of actionPerformed().

(This would be awful in an enterprise scenario, but in a single-VM model like in Swing, it should work just fine)