Yeah, that's what we figured while playing with it, but it's not the most
elegant solution. Maybe we should make that configurable in trinidad-config
(not supporting EL)? Most users can probably deal with the issue so it
should not save the scope by default when it's empty, but users needing it
would be able to without using that hack, because that's really what it is.
~ Simon
On 9/28/07, Adam Winer <[EMAIL PROTECTED]> wrote:
>
> It's a long-standing problem with form URL encoding.
>
> If you don't add anything to pageFlowScope until Render Response,
> those objects will be lost, 'cause the token is written out on the
> form too early. We try to be conservative and not generate new
> pageFlowScopes unless its necessary.
>
> The "workaround" is to make sure that at least one object
> gets set on the pageFlowScope by beforePhase() of
> Render Response. Could be :
> pageFlowScope.put("foo", "bar");
> ... doesn't matter what.
>
> -- Adam
>
>
> On 9/28/07, Simon Lessard <[EMAIL PROTECTED]> wrote:
> > Hi all,
> >
> > We have a client who played with page flow scope and bit and came to the
> > following. Of course, the use case is extremely synthetic, but it's
> still
> > strange:
> >
> > page.jspx
> > <f:view>
> > <tr:document>
> > <tr:form>
> > <tr:inputText value="#{bean.value}"/>
> > <tr:commandButton text="Go"/>
> > </tr:form>
> > </tr:document>
> > </f:view>
> >
> > Bean.java
> > public class Bean
> > {
> > public Bean()
> > {
> > RequestContext rContext =
> > RequestContext.getCurrentInstance ();
> >
> > Map<String, Object> pageFlowScope = rContext.getPageFlowScope();
> >
> > if (!pageFlowScope.containsKey("someKey"))
> > {
> > System.out.println("Creating the long to create object and we sure
> > don't want to create it twice for the page flow");
> > pageFlowScope.put("someKey", getAnExpensiveToCreate Object());
> > }
> > }
> >
> > public String getValue()
> > {
> > RequestContext rContext =
> > RequestContext.getCurrentInstance ();
> >
> > Map<String, Object> pageFlowScope = rContext.getPageFlowScope();
> >
> > return
> > ((SomeClass)pageFlowScope.get("someKey")).getStringAttribute();
> > }
> >
> > public void setValue(String value)
> > {
> > RequestContext rContext =
> > RequestContext.getCurrentInstance();
> >
> > Map<String, Object> pageFlowScope = rContext.getPageFlowScope();
> >
> >
> > ((SomeClass)pageFlowScope.get("someKey")).setStringAttribute(value
> > );
> > }
> > }
> >
> > With that code, the expensive object is going to be created twice, when
> the
> > page is first rendered and on first postback. This happen because at the
> > time the form is rendered, the page flow scope is still empty (bean was
> > never referenced) and the default behavior in that case is to not add
> the
> > token to the action url thus losing the object. Therefore, if you change
> the
> > page to
> >
> > page.jspx
> > <f:view>
> > <tr:document>
> > <tr:outputText value="#{bean.value}"/>
> > <tr:form>
> > <tr:inputText value="#{bean.value}"/>
> > <tr:commandButton text="Go"/>
> > </tr:form>
> > </tr:document>
> > </f:view>
> >
> > Then the expensive object get created only once. Personally I think we
> > should consider that a bug as it's very counter intuitive and hard to
> debug.
> > Am I missing something?
> >
> >
> > Regards,
> >
> > ~ Simon
> >
>
