JSF problem on submit event

Question

Hi to everyone and sorry for my english,
i've created a web form using jsf tecnology.
This form contain 2 combo (selectOneMenu) one of this combo contain the region of Italy, so when an user select a region in this combo, on the second combo i'm load the city of this region, for make this i've an onChange event on the first combo this event meke a submit of form, i've also setted the property "immediate" = true.
So when the first combo chenge value if i've in the form a inputText with property required = "true" the form show me the error message "field required", but i've set immediate = "true"?
How i can bypass this problem.
Thanxs a lot,
Fabio.

Answer 1

You should still use a value change listener. Putting db calls into your getters should be a last resort anyways. This is because JSF will call getters multiple times, thus causing you to make multiple DB calls.
Plus, if you don't call renderResponse(), you're going to continue seeing your error message. Setting the immediate attribute doesn't necessarily skip the validation phase, rather, it processes validation in the Apply Request Values phase.
Anyways, messing with the JSF phases can be a tricky concept for a newer person to understand. However, you should learn what you can about the standard JSF lifecycle.
Getting to your problem at hand... The quick version is that you need to create a value change listener, attach it to the first combo box (region1), configure the value change listener to retrieve the appropriate values from DB, then set the second combo box (city1) options, and then call renderResponse().
Here's some code to get you started.
In your jsp:
<h:selectOneMenu id="region1" value="#{userBean.selectedRegion1}"
    onchange="submit" immediate="true"
    valueChangeListener="#{userBean.regionSelected}">
</h:selectOneMenu >In your UserBean class, create the following method:
     public void regionSelected(ValueChangeEvent event)
          throws AbortProcessingException {
          //Get the selected region from the event
          String region = (String)event.getNewValue();
          //Set the selected region in your bean
          setSelectedRegion(region);
          //Call DB to retrieve the city list for the selected region
          //Build Select Items list from record set
          //Set the city list with the new select items
          setCityList(newCityList);
          //Force to render response phase so that any error messages DO NOT get
          //displayed. i.e. Skip update model phase. Use immediate="true" on the
          //component that calls this valueChangeListener so that it does not
          //run any validation.
          FacesContext.getCurrentInstance().renderResponse();
     }That should get you good and started.
CowKing