javascript - Sencha touch 2 ajax 回调函数作用域

Question

我在调用 Ext.Ajax.request 时遇到程序范围问题。我需要能够从 ajax 回调函数访问周围的 Ext.data.Model 实例。实现这一目标的正确方法是什么？我在 sencha touch 2 中这样定义数据模型:

Ext.define('AlbumsData', {
extend: 'Ext.data.Model',
requires: [
    'Ext.Ajax'
],
config: {
    fields: [
        {name: 'someData',  type: 'string'}
    ]
},
getData: function(){
    Ext.Ajax.request({
        url : '/somedata.json',
        callback: function(options, success, response) {
            //I want to access the surrounding model instance here and "this" certainly doesn't return the instance of the "Ext.data.Model" in which this getData() method is.
        }
    });
}

Answer 1

使用 scope 选项:

getData: function(){
    Ext.Ajax.request({
        url : '/somedata.json',
        callback: function(options, success, response) {
            //I want to access the surrounding model instance here and "this" certainly doesn't return the instance of the "Ext.data.Model" in which this getData() method is.
        },
        scope: this
    });
}