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javamultithreadingswingswingworker

Prevent Swing GUI from becoming unresponsive when invoking a method which is both accessing Swing components and is time-consuming

The following line:

SwingUtilities.updateComponentTreeUI(aComponent);

is making my GUI unresponsive.

When invoking this method to update the laf on a large portion of a GUI, it takes a lot of time, and so makes the GUI unresponsive during this operation.

Since this operation is manipulating the GUI, one can't use a SwingWorker for this either. From the SwingWorker documentation:

  • Time-consuming tasks should not be run on the Event Dispatch Thread. Otherwise the application becomes unresponsive.

  • Swing components should be accessed on the Event Dispatch Thread only.

The problem here though, is that the operation is accessing Swing components and is time-consuming.

Is there a good way to prevent this unresponsiveness?

Solution

  • Since what you do is changing the L&F, and that might severely impact the appearance and usability of the GUI, ask yourself whether you really want the application to be responsive during that time. It may be better to display a message ("Please wait..." or something) using the glass pane, and freeze the GUI while the L&F is updated.

    Now, as others have suggested, you may want to investigate why updating the component tree is so slow.