Re: Design Question for Model and View

From: (Stefan Ram)
30 May 2007 20:24:38 GMT
Jason Cavett <> writes:

The problem I run into (sort of a problem - I can easily hack around
it, but I'm wondering if there's a better way) is that it can be tough
getting information from the user when I need to accomplish a goal.

  For example, a model operation might need a yes/no-information.

  According to MVC, the model then would change a variable
  ?information_required? to be ?true?. The View would be
  subscribed to this as an observer and, thus, become notified
  of the need. The view will create a yes/no-requester visible
  to the user.

  When the user decides to supply the information, the
  controller will tell the model, which then will set
  ?information_required? to ?false?, which will make the view to
  close the requester.

the model notifies that view

  The model must not know that there is a view, otherwise it
  would be coupled to the view in a way that is not intended in

  It only knows that there are observers, so it ... (see above)

The view sets a flag in the main model notifying that it should

  In MVC, this would be the part of the ?controller?.

  But then, maybe you did not want to use MVC at all.

Is this a good way to go about it?

  I can not determine, whether a strict and pure application
  of MVC is advantageous in your case. I just wrote /how/ to
  do it /if/ one wanted to do this.

  Things might be simplified by a kind of ?hierarchical MVC?,
  where the confirmation-logic is contained entirely in the View
  of the outer MVC, while it consists of an internal MVC
  structure itself.

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