Review Request: State machine architecture for PMC

[Aaron J. Seigo]

On April 8, 2010, Christophe Olinger wrote:
> One thing missing is the layout of the actual subComponents in the applets.
> Currently they are just added in a row. For this we need the API. The
> layout should recognize which type of applet arrives and lay it out
> accordingly. That means lots of if/thens within tha applet code. This also
> means adding new states with new subcomponents would mean adding if/tehns
> to the actual addToLayout functions in the applets.

what i'd recommend is to provide a way to tag subcomponents with values (e.g. 
an enum) that says something about what they do.

divide up each MainComponent into "zones" (navigation, media playing, status, 
whatever :) and then each sub component can be tagged by the creator of the 
sub component (e.g. a state) with what it is. 

then the main components will know which zone they belong in.

from there, i'd go with a naive implementation, at least at first, that just 
puts things into the respective zones on a first-come-first-placed basis.

this alleviates the needs for if/else and odd interactions between state 
plugins and the main components that need to lay out a plugin's custom sub 
components.

-- 
Aaron J. Seigo
humru othro a kohnu se
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