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Re: [platform-ui-dev] Parameterized Commands (was 'Key Binding Problem')
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On March 9, 2004 02:10 pm, Ed Burnette wrote:
> I'm a bit unclear (ok, more than a bit) as to the difference between
> Commands and Actions. If we have Actions, why do we need Commands?
Commands are an attempt clean up and unify the rather diverse and complex
world of actions and contributions. They also provide a little more
flexibility than actions were generally designed for -- by cleanly separating
user interface elements from "commands" to be performed in the underlying
system.
Command is the abstraction of a semantic. An example of a command might be
"copy" or "delete". A handler is some code that explains how the semantic
applies in a particular context. For example, a handler might explain how
"delete" works within the package explorer. Neither of these are tied to the
user interface.
An action is a combination of a command, a single handler, and some user
interface details. A retargettable action is very similar to a command with
user interface details.
d
