javascript - Web 组件 : attributeChangedCallback not fired

Question

这是一个基本的 hello world 网络组件。更改属性“who”时不会触发 attributeChangedCallback。检查 fiddle

MyElementProto.attributeChangedCallback = function(attr, oldVal, newVal) {
    console.log('attributeChangedCallback triggered');
        if (attr === 'who') {
            this.setWho(newVal);
        }
    };

https://jsfiddle.net/y3kj81nz/5/

Answer 1

您需要使用 setAttribute方法:

window.changeWhoAttr = function() {
    var el = document.querySelector('#custom-tag');
    el.setAttribute('who', 'Universe'); // Instead of el.who = 'Universe'
    console.log('changeWhoAttr triggered');
}

Fiddle