Splitting rules for graceful degradation of user interfaces

This paper presents a series of new algorithms for paginating interaction spaces (i.e.; windows, dialog boxes, web pages...) based on a multi-layer specification in a user interface description language. We first describe how an interaction space can be split using information from the presentation layer (Concrete User Interface). We then demonstrate how information from higher levels of abstraction (Abstract User Interface, Task model) can be used to produce a pagination that is more meaningful from the task's viewpoint than other techniques. The pagination relies on a set of explicit splitting rules that can be applied as the first step in a graceful degradation. These splitting rules are implemented as an interface builder plug-in which automatically generates code under the designer's control.