MVC: info on update method
Hi,
I'm using MVC pattern.
I've understood it, and I be able to use it, but I've some doubts.
Practically, in the view I have the update method;
Now, my view interact with many models, which advice it by executing his update method.
But in this update method, I've various pieces of code;
one for the update of the first model;
one for the update of the second model;
etc.....
I don't like this, because I want that,
when a model is updated, it advice view by executing only the corresponding piece of code.
Is there any other solution?
Excuse me if it's not clear.
Thank you in advance
MargNat
[691 byte] By [
MargNata] at [2007-11-26 17:50:23]
# 2
I take it from your message that you're implementing a Swing-based MVC GUI (things would be hardly different for a Web MVC application).
In this Swing GUI, the View is an Observer of the Model, hence your update() method, correct?
Indeed you don't have to apply this blindly : you may very well have each model have its own Observer interface; indeed in the Java world, an Observer is usually implemented as a "Listener" idiom, which provides more strongly typed notification methods.
So you can have your ModelA notify a (set of) ModelAListener object where ModelAListener is an interface providing a modelAUpdated(ModelA model), same for ModelB and ModelC.
Then your view ony has to implement ModelAListener, ModelBListener, ModelCListener, and provide model-specific code in each model-specific method modelAUpdated(ModelA), modelBupdated(ModelB), modelCUpdated(ModelC).
SO when the ModelC instance is updated, it invopkes it's listener's modelCUpdated(ModelC) method, which only takes care of ModelC's changes.
All 3 methods could even have the same name modelUpdated(...) or update(...), with a different type of parameter each, the overloading specifying which Model has changed (but IMHO this would go against clarity of the code).
