Model View Presenter; Twisting the triad

Andy Bower is a Director and founder of Object Arts Ltd, the UK based company responsible for Dolphin Smalltalk. Andy has been a practitioner of Object Oriented Programming since he discovered the "Blue Book" back in 1984 although, by his own admission, he didn't actually get to grips with the Smalltalk language until some ten years later. In 1994, Andy "saw the light" and became a key member of the team that designed and built Dolphin Smalltalk. He is now a "raving" Smalltalk evangelist and, therefore, not someone who should be engaged in conversation at parties!

Model View Presenter (MVP) is a modern user interface framework for Smalltalk. Derived from the Taligent CModel View Presenter; Twisting the triad framework of the same name, MVP is currently the key UI framework in Dolphin Smalltalk. This tutorial discusses the qualities of MVP and why the Dolphin developers chose to adopt it over and above two previous framework designs (that were tried, and yet rejected) based around widgets and MVC. The presentation will attempt show how, by rotating (or twisting) the MVC triad, one can produce an "Observer" based framework that is easy to use and more flexible than those currently available in other Smalltalk environments. We will also present some "hands-on" step-by-step examples for those interested in getting to grips with Dolphin MVP for the first time.