Bug 153993 [Viewers] Common Baseclass for Tree/TableEditorImpl
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/ColumnViewer.java
* provides only the label text and image for the first column, and any
	 * remaining columns are blank. Implementers of <code>ILabelProvider</code>
	 * may also implement {@link IColorProvider} and/or {@link IFontProvider} to
	 * provide colors and/or fonts.
	 * </p>
	 * <p>
	 * If the label provider implements the mixin interface ITooltipProvider, it
	 * can provide custom tooltips.
	 * </p>
	 */
	public void setLabelProvider(IBaseLabelProvider labelProvider) {
		Assert.isTrue(labelProvider instanceof ITableLabelProvider
				|| labelProvider instanceof ILabelProvider
				|| labelProvider instanceof CellLabelProvider);
		updateColumnParts(labelProvider);
		super.setLabelProvider(labelProvider);
	}
	/**
	 * Clear the viewer parts for the columns
	 */
	private void updateColumnParts(IBaseLabelProvider labelProvider) {
		ViewerColumn column;
		int i = 0;
		
		while( ( column = getViewerColumn(i++) ) != null) {
			column.setLabelProvider(CellLabelProvider.createViewerLabelProvider(labelProvider));
		}
	}
}