[Cuis] PluggableListMorph

[Juan Vuletich]

Hi Dan,

On 20/10/2015 05:43 p.m., Dan Norton wrote:
> Greetings,
>
> PluggableListMorph has valuable behavior but applying it in morphs with multiple lists can be
> daunting because of the use of the dependency mechanism. AFAICT the tools do not display
> dependencies and even if they did, it's not clear why some of them exist.

Yes. Most tools are still using the changed:/update: dependency 
mechanism that comes from MVC in Smalltalk-80.

Later, Squeak and Cuis also included the #when:send:to: event system. It 
should replace changed:/update: in all client code because it helps 
produce code that is easier to understand. This is something we should 
do at some moment.

> What is needed is a "PluggableListMorph Principles of Operation" doc, or something similar
> that can be in the Terse Guide. It should show an example of selection in one list causing the
> population of another list and selection in that list causing the population of some other
> morph. Isn't that like FileList? Yes, but we need the whys and wherefors. For example, a
> method sends #changed: with a parameter referring to another method - why? The design
> needs to be explained.
>
>   - Dan

Most likely all the classic references apply (In the blue book? Or most 
likely in Inside Smalltalk vol II). I'm sure there are others. Including 
excepts and/or references to them in TerseGuide would indeed be great.

Please also keep in mind that this is not only for lists. It is 
essentially the same mechanism used for text panes, buttons, lists, tree 
lists, etc.

Thanks,
Juan Vuletich