Ajax Framework - Dropdown

Dependent dropdowns implemented with p:ajax behavior.

Select a Location

<h:form>
    <p:growl id="msgs" showDetail="true" />

    <p:panel header="Select a Location" style="margin-bottom:10px;">
        <h:panelGrid columns="2" cellpadding="5">
            <p:outputLabel for="country" value="Country: " />
            <p:selectOneMenu id="country" value="#{dropdownView.country}" style="width:150px">
                <p:ajax listener="#{dropdownView.onCountryChange}" update="city" />
                <f:selectItem itemLabel="Select Country" itemValue="" noSelectionOption="true" />
                <f:selectItems value="#{dropdownView.countries}" />
            </p:selectOneMenu>

            <p:outputLabel for="city" value="City: " />
            <p:selectOneMenu id="city" value="#{dropdownView.city}" style="width:150px">
                <f:selectItem itemLabel="Select City" itemValue="" noSelectionOption="true" />
                <f:selectItems value="#{dropdownView.cities}" />
            </p:selectOneMenu>
        </h:panelGrid>

        <p:separator />

        <p:commandButton value="Submit" update="msgs" action="#{dropdownView.displayLocation}" icon="pi pi-check" />
    </p:panel>
</h:form>