Hello I develop some complex interface with XML object based data model. The model is similar to Cairngorm's ModelLocator. It allows me to implement undo/redo system, holding in separate XML object changes in main data model reflecting users gestures. However, as far as I know, common undo/redo systems register not data model changes, but user commands. This approach is less useful in my case, since some user commands request a lot of information from the server, so repeating them would be highly undesirable. I will really appreciate professional opinion regarding the problem and links to related topics.
Beforehand grateful Leon
