>From: "Ian.Priest" <[EMAIL PROTECTED]>
>
> Hey all,
>
> I'm looking for guidance on a "nice" way of doing something.
>
> I have a page with two component on it. One is a "Select country"
> drop-down and one is a "phone-number" input text. The latter has a small
> text prefix that shows the international dialling code for the selected
> country. Both fields are required.
>
> The Country drop-down has onChange()="submit();" and a
> ValueChangeListener method on the ViewController. When a new country is
> chosen:
>
> The form is submitted.
> The ValueChangeListener looks up the international dialling code for the
> chosen country and sets a value on the bean
> The ValueChangeListener calls renderResponse().
> The view is rendered with the dialling code displayed just before the
> phone-number field.
>
> The problem lies here. If having selected a country I now submit the
> form without entering a phone-number the form validation fails because
> the phone-number feild is required. That means (JSF lifecycle) that the
> bean values are not initialised from the request. That means that my
> dialling-code bean property is now null again and so disappears when the
> view is re-rendered with the error.
>
> To fix it, in prerender() I check for (diallingCode == null &&
> isPostBack()), assume it's an error condition and look up the value of
> the dialling code from the requestParameterMap like this:
>
> public void prerender() {
>
> String isoCountryCode =
> getAddresses()[0].getCountry().getIsoCountryCode();
>
> // If the isocode is null and this is a postback it indicates
> // some validation error. Get isocode from the request
> if ( isoCountryCode == null && isPostBack() ) {
> Map requestParameterMap =
> getFacesContext().getExternalContext().getRequestParameterMap();
> Set set = requestParameterMap.keySet();
> for (Object key : set) {
> if ( key.toString().endsWith("country") )
> isoCountryCode = (String)
> requestParameterMap.get(key);
> }
> }
>
> initDiallingCode(isoCountryCode);
> }
>
> That fixes my bug. But am I looking up the value in the best way? How
> would others fix this problem?
>
You might take a look at Shale remoting. David Geary just submitted a good
overview.
http://shale.apache.org/features-remoting.html
David also has a slick Ajax/remoting example in the shale usecases that
populates a city and state based on a zip code selected from a droplist.
> Cheers,
> Ian.
>
Gary
>
>
>
>
>
