* into the text area.
* @see #removeTrackingIcon(Object)
*/
public GutterIconInfo addOffsetTrackingIcon(int offs, Icon icon, String tip)
throws BadLocationException {
Position pos = textArea.getDocument().createPosition(offs);
GutterIconImpl ti = new GutterIconImpl(icon, pos, tip);
if (trackingIcons==null) {
trackingIcons = new ArrayList<GutterIconImpl>(1); // Usually small
}
int index = Collections.binarySearch(trackingIcons, ti);