ExtJSv7：实现Ext.mixin.Observable时出错

Question

我们正在尝试在ViewController中实现Ext.mixin.Observable，下面的代码段

mixins: ['Ext.mixin.Observable'],
constructor: function(config){
  this.mixins.observable.constructor.call(this, config);
},

但是这会在Viewcontroller中引发this.mixins.observable.constructor.call(this, config);的错误

BaseController.js?_dc=1587282588103:440 Uncaught TypeError: Cannot read property 'listen' of undefined
    at constructor.listen (BaseController.js?_dc=1587282588103:440)
    at constructor.callParent (Base.js?_dc=1587282588090:1479)
    at constructor.listen (ViewController.js?_dc=1587282588091:206)
    at constructor.updateListen (BaseController.js?_dc=1587282588103:257)
    at constructor.setter [as setListen] (Config.js?_dc=1587282588102:329)
    at Ext.Configurator.configure (Configurator.js?_dc=1587282588102:674)
    at constructor.initConfig (Base.js?_dc=1587282588090:1650)
    at constructor (Observable.js?_dc=1587282588091:437)
    at constructor (MainController.js?_dc=1587282588090:6)

这里可能出了什么问题，我遵循了sencha文档中Ext.mixin.Observable的文档

Answer 1

看起来像您在调用可观察的构造函数后错过了构造函数中的this.callParent(arguments)