private void showProgress(final int delay) {
		Runnable r = () -> {
			if (delay <= 0) {
				showProgressPanel(true);
			}
			else {
				showTimer = new Timer(delay, ev -> {
					if (isBusy()) {
						showProgressPanel(true);
						showTimer = null;
					}
				});
				showTimer.setInitialDelay(delay);
				showTimer.setRepeats(false);
				showTimer.start();
			}
		};
		SwingUtilities.invokeLater(r);
	}
Passing a value of <code>false</code> signals to disable the {@link JTree}'s default behavior
of showing handles for leaf nodes until they are opened.

@param enable False to disable the default JTree behavior
Ghidra/Framework/Docking/src/main/java/docking/widgets/tree/GTree.java