hi,
this is not entirly correct, since there are cases in which jsf
doesn't do all the hard work. two cases that I met more than once are:
1) presenting report output in a datatable according to filtered
criteria.
2) saving state of one screen even if validation fails and restoring
this state after doing some action in another page.
i admit it is not jsf responsibility to give direct answers to these
issues, but it is the kind of cases I fall back to good old
servletRequest or use some comlementing technology.
Sent from my iPhone
On 29/11/2008, at 17:55, "Hazem Saleh" <[EMAIL PROTECTED]> wrote:
Hello mates,
I just want to note that one of the JSF good things is to allow
developers to bind the components directly with model without
having to directly hack the request parameters, and model methods
should be called in the action of the components (INVOKE_APPLICATION
phase).
JSF is a component-oriented framework. JSF application developer
should not care about (ServletRequest) as binding is done
automatically by the framework.
So if one finds (him/her)self having to talk directly with
(ServletRequest) inside the JSF application then (s)he should do
some refactoring to eliminate these direct calls.
Thank you mates.
On Sat, Nov 29, 2008 at 3:09 PM, santosh chouhan <[EMAIL PROTECTED]
> wrote:
Thank you very much Justinas.
Santosh Chouhan
On Sat, Nov 29, 2008 at 6:20 PM, Justinas <[EMAIL PROTECTED]>
wrote:
santosh chouhan wrote:
Hello Justinas,
Which one is called first , is there any case possible where Ui
component can directly connect to model bean . please any one give
the exactly scenario of beans when they come in action.
First called is backingbean. Then bb does some logic, and calls model.
To call model method directly from UI component is bad, because,
during page rendering very often bindings are called more than once.
You could see that in effect when you put
system.out.println("sometext") in BB setter or getter method!
Backing beans are helpers, temp value storage for UI component or
group of them. They take data from Model beans.
Usually I put BB in request scope, and in constructor I initialize
it using calls to Model classes according to request parameters. In
that way, model beans are called once per request and backing bean
hold values as long as it takes to render page.
From which beans i get my form attribute , please make me clear
all step
h:dataTable value="#{myBB.dataModel}"
BB:
private DataModel dataModel;
constructor:
this.dataModel = new
ListDataModel(
MyModel.getItemList(Contexts.getRequestParam('parent_id'));
where Contexts.getRequestParam is helper function to extract post/
get parameter from HttpRequest.
MyModel.getItemList() - static method, returning List of items. It
encapsulates required SQL and so on.)
hope that clears things up!
Justinas
--
Hazem Ahmed Saleh Ahmed
Author of (The Definitive Guide to Apache MyFaces and Facelets):
http://www.amazon.com/Definitive-Guide-Apache-MyFaces-Facelets/dp/1590597370
Web blog: http://www.jroller.com/page/HazemBlog
[Web 2.0] Google Maps Integration with JSF:
http://code.google.com/p/gmaps4jsf/
http://www.theserverside.com/news/thread.tss?thread_id=51250
