Bug 48364 PreferenceDialog can reopen empty
20031209 When you close the Preferences dialog with an entry other than the default selected you will get an empty entry in the dialog when you reopen STEPS 1) Open the preferences dialog 2) Select the Appearances page 3) Close the dialog 4) Reopen - Workbench will be selected and the contents will be empty
bundles/org.eclipse.jface/src/org/eclipse/jface/preference/PreferenceDialog.java
}
	/**
	 * Updates this dialog's controls to reflect the current page.
	 */
	protected void update() {
		
		updateTitle();
		
		updateMessage();
		
		updateButtons();
		
		setSelectedNode();
	}
	/* (non-Javadoc)
	 * @see org.eclipse.jface.preference.IPreferencePageContainer#updateButtons()
	 */
	public void updateButtons() {
		okButton.setEnabled(isCurrentPageValid());
	}
	/* (non-Javadoc)
	 * @see org.eclipse.jface.preference.IPreferencePageContainer#updateMessage()
	 */
	public void updateMessage() {
		String pageMessage = currentPage.getMessage();
		int pageMessageType = IMessageProvider.NONE;
		if (pageMessage != null && currentPage instanceof IMessageProvider)
			pageMessageType = ((IMessageProvider) currentPage).getMessageType();
		String pageErrorMessage = currentPage.getErrorMessage();