Object-Oriented Construction Handbook

8.9 THE FEEDBACK BETWEEN INTERACTION FORMS AND IP PATTERN

INTENT

We introduce a solution that uses the command pattern (Gamma et al.) to solve the feedback problem between interaction forms and IP.

PROBLEM

User actions such as mouse or keyboard movements are accepted by the window system. The window system converts these actions into system events, which are initially passed on to the representation and interaction forms. For this purpose, representation forms are normally linked to the appropriate widgets of the window system over a callback (or over subclasses and the bridge pattern). Interaction forms convert system events into program events by alerting the IP. This requires an interaction form to be linked to the IP. The IP can then ...