Bug 213166 [Viewers] Problems with OwnerDrawLabelProvider.setUpOwnerDraw
3.4 M4 To set up the owner draw callbacks for a viewer OwnerDrawLabelProvider.setUpOwnerDraw is offered. The problem of this is: a. there's no way to uninstall the callbacks. In our views we want to allow to enable and disable owner draw in the preferences b. from an API client perspective, it would be nicer if the label provider could install itself when installed. A good solution would be to add more life cycle to a label provider. CellLabelProvider.initialize(ColumnViewer, int column) There's already ILableProvider.dispose when a label provider is removed from a viewer.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/OwnerDrawLabelProvider.java
protected abstract void paint(Event event, Object element);
	/**
	 * Handle the measure event.
	 * 
	 * @param event
	 *            the measure event
	 * @param element
	 *            the model element
	 * @see SWT#MeasureItem
	 */
	protected abstract void measure(Event event, Object element);
	/**
	 * Create a new instance of the receiver based on a column viewer.
	 * 
	 */
	public OwnerDrawLabelProvider() {
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.viewers.ViewerLabelProvider#update(org.eclipse.jface.viewers.ViewerCell)
	 */
	public void update(ViewerCell cell) {
		
		Rectangle cellBounds = cell.getBounds();
		cell.getControl().redraw(cellBounds.x, cellBounds.y, cellBounds.width,
				cellBounds.height, true);
	}
}