public SimpleItemListModel<T> setItemActionIconMapper(final Function<T, ImageParam> actionIconMapper) {
        if (actionIconMapper != null) {
            this.actionIconMapper = actionIconMapper;
            triggerChange(ChangeType.COMPLETE);
        }
        return this;
    }
Sets a mapper providing an optional action icon per item. For each item where the action item
 is non-null, it is displayed and the listener provided via {@link #setItemActionListener(Consumer)} is fired
main/src/main/java/cgeo/geocaching/ui/SimpleItemListModel.java