User interfaces (UIs) comprise reactive systems whose behaviour often
involves a complex notion of timing and state. Implementing this logic
directly in a general-purpose programming language can be nontrivial,
leading to applications that are slow to develop and error-prone. Previous
work has demonstrated that Statecharts, a graphical language for modelling
timed, reactive, stateful systems, can be used effectively to design,
prototype, and synthesize complex user interfaces. This reduces the
accidental complexity involved in user interface development, allowing
developers to focus only on the remaining essential complexity, which
ultimately leads to greater developer productivity, and faster, more robust
Web user interfaces are built on a standard suite of Open Web technologies,
effectively on the Web, a Statecharts interpreter or compiler implemented
specifically, SCION implements the SCXML draft specification, an emerging
W3C standard which provides an XML syntax and semantics for Statecharts.
This talk will provide a practical examination of techniques to apply SCXML
and SCION to real-world UI development today.