We need to support high contrast mode display. Currently we use GXT 2.2.4, the icons (such as a folder) on a tree item will not show under high contrast mode. Currently we can override setIconStyle(String style) of TreeItem.class to use specfic icon when need, but the parameter for setIconStyle() should match a CSS style that specifies a background image, due to thus implementation, the icon will not show under contrast mode. In order to show the icons under high contrast mode, we need to set the icon not by the CSS style while use something like "<img src='icon path' class='style name'">, but so far, we cannot find an interface which we can override to reach this target.
So, my question is that: is there any considerate about high contrast mode on TreeItem and related components in GXT? What should we do based on current GXT implementaion so that the icons on a tree item could be show normally under high contrast mode?
Any suggestion will be highly appreciate.

Thanks & Best Regards,