widget.getTitle is not a function

[fritz1126]

本人刚接触ODOO，参考网上分享的案例尝试widget开发，注册了一个客户端动作，代码如下：

odoo.define('load_echarts', function (require) {
    "use strict";
    var core = require('web.core');
    var Widget = require('web.Widget');

    // 定义打开模板
    var Echarts = Widget.extend({
        // 模板名称 对应上面xml中t-name
        template: 'echarts_capa_homepage',

        init: function(parent, data){
            return this._super.apply(this, arguments);
        },

        start: function(){
            return true;
        },

    });

    // 将上面定义的打开模板注册成客户端动作名对应client_action中的tag
    core.action_registry.add('load_echarts.load_capa_homepage', Echarts);

})

但运行的时候报错了，错误信息如下：

TypeError: widget.getTitle is not a function
    at Class._executeClientAction (http://localhost:8069/web/static/src/js/chrome/action_manager.js:446:27)
    at Class._handleAction [as _super] (http://localhost:8069/web/static/src/js/chrome/action_manager.js:669:29)
    at Class._handleAction (http://localhost:8069/web/static/src/js/chrome/action_manager_act_window.js:404:28)
    at Class.<anonymous> (http://localhost:8069/web/static/src/js/core/class.js:123:38)
    at Class._handleAction (http://localhost:8069/web/static/src/js/chrome/action_manager_report.js:164:28)
    at Class._handleAction (http://localhost:8069/web/static/src/js/core/class.js:123:38)
    at http://localhost:8069/web/static/src/js/chrome/action_manager.js:165:25

琢磨了很久也都没头绪，向大神们求助……:disappointed_but_relieved_face: :disappointed_but_relieved_face: :disappointed_but_relieved_face: