Well, I'm not sure why I thought this is about some Catalog Item, it clearly isn't. As for the original problem, the requirement is not supported OOB. Though it seems like one deals with two fields, the drop-down and the text entry are a single field and only the text entry is exposed through the g_form API.
If you are OK with DOM manipulation a solution would be to create on onLoad Client Script for Incident that wires up an event listener, so you can know when the country has been selected:
function onLoad () {
var element = 'u_bridge_phone_number',
select = g_form.getControl('country_' + g_form.getTableName() + '.' + element);
if (select && typeof select.addEventListener == 'function')
select.addEventListener('change', callChange(select));
function callChange (select) {
var oldValue = getValueOfSelect(select);
onChange(select, oldValue, oldValue, true, false);
return function (event) {
onChange(event.target, oldValue, getValueOfSelect(event.target), false, false);
};
}
function getValueOfSelect (select) {
return select.selectedIndex > -1 ? select.options[select.selectedIndex].textContent : '';
}
function onChange (control, oldValue, newValue, isLoading, isTemplate) {
// This is where one can implement any logic that must run when the
// country is changed. E.g. do a GlideAjax call to fetch the number
// Based on newValue, which will be a label, like North America, etc...
if (isLoading || newValue === '') {
//return;
}
console.log('change', control, oldValue, newValue, isLoading, isTemplate);
}
}
You can than implement the lookup in function change, where the comments say. You should create lookup table to store the country - phone number list. With help of GlideAjax, based on the selected label, you can obtain the phone number to use - this can be filled using the regular g_form.setValue() call.
A week point of the solution (besides the DOM manipulation part and only working in UI16!, of course) is localization. The code uses the drop-down label for newValue and oldValue. This is to enable differentiation between Canadian and United Sates phone number which all start with 1+. But if an agent uses a non-English locale for himself, the label will no longer be in English and your solution will not work for him. This can be solved either by re-implementing function getValueOfSelect to return something else and select the phone number by that value, or by selecting the phone number through a Decision Table based on localized labels.
Hope this all helps.
