Sample usage of the OnOutputChange event for model-driven app forms Client API

AccountForm.js

var MEA = window.MEA || {};
var accountForm = MEA.accountForm || {};

(function () {
    this.OnLoad = function (onLoadContext) {
        var formContext = onLoadContext.getFormContext();
        var phoneControl = formContext.getControl('telephone1');
        phoneControl.addOnOutputChange(this.OnOutputChangeHandler);
    };
    this.OnOutputChangeHandler = function (OnOutputChangeContext) {
        let attribute = OnOutputChangeContext.getEventSource();
        let formContext = OnOutputChangeContext.getFormContext()
        switch (attribute.getName()) {
            case 'telephone1':
                let telephone1Control = formContext.getControl('telephone1');
                let telephone1ControlOutput = telephone1Control.getOutputs();
                let isValidTelephone1 = telephone1ControlOutput["telephone1.fieldControl.isValid"].value
                if(!isValidTelephone1){
                    telephone1Control.setNotification('Telephone1 is not valid','telephone1ControlNotification');
                }
                else {
                    telephone1Control.clearNotification('telephone1ControlNotification');
                }
                console.log(this.isValid_telephone1);
                break;
            default:
                break;
        }
    }
}).call(accountForm);