Bug 5571 JAR Packager: Reveal first checked project
If the list of projects in the JAR Packager is long it is possible that the shown projects are not checked even though there are checked projects (due to current selection). ==> reveal the first checked project.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/jarpackager/JarPackageWizardPage.java
}
	/*
	 * Overrides method from IJarPackageWizardPage
	 */
	public boolean isPageComplete() {
		setErrorMessage(null);
		return super.determinePageCompletion();
	}
	/*
	 * Implements method from Listener
	 */	
	public void handleEvent(Event e) {
		if (getControl() == null)
			return;
		update();
	}
	
	protected void update() {
		updateModel();
		updateWidgetEnablements();
		updatePageCompletion();
	}
	
	/*
	 * Overrides method from WizardDataTransferPage
	 */
	protected boolean validateDestinationGroup() {
		if (fDestinationNamesCombo.getText().length() == 0) {
			return false;
		}