无法访问knockout.js mvvm中的viewmodel来操纵项目

Question

我正在使用Knockout.js，require.js等MVVM web应用程序。问题是我无法访问属性（类型observable数组）在我的viewmodel。

合同样本模型：

define('model.contract', ['ko'], 
    function (ko) { 
     var Contract = function() { 
      var self = this; 
      self.id = ko.observable(); 
      self.subject = ko.observable().extend({ required: true }); 

      self.shoppingItems = ko.observableArray(); 

      }; 
      return Contract; 
    }); 

样品视图模型：

define('vm.contract', ['ko'], 
    function (ko) { 
     var contract = ko.observable(), // Is initialised as viewmodel activates 

      deleteCmd = function() { 

       var selectedId = getSelectedId(), 
        deletedId = contract.shoppingItems.remove(function (item) { return item.id === selectedId; }); 

       alert('Item ' + deletedId[0].id + ' was deleted!'); 
      }; 

     return { 
      contract: contract, 
      deleteCmd: deleteCmd 
     }; 
    }); 

样的看法：

<div data-bind="template: {name: shoppingItemTemplate, foreach: contract().shoppingItems}"></div> 
<button data-bind="click: deleteCmd">Delete Selected</button> 

所有我需要在视图模型访问是contract.shoppingItems和我得到的是未定义。

Answer 1

为什么你定义你的contract为observableArray而不是仅仅是observable？

也不要忘了，你应该叫contract()得到的contract观察到的值：

// ... 
deletedId = contract().shoppingItems.remove(function (item) { return item.id === selectedId; }); 
// ... 

更新： 只注意到你正确定义model.contract。请将您的return ContractContract定义块之外:)

define('model.contract', ['ko'], 
    function (ko) { 
     var Contract = function() { 
      var self = this; 
      self.id = ko.observable(); 
      self.subject = ko.observable().extend({ required: true }); 

      self.shoppingItems = ko.observableArray(); 
     }; 

     return Contract; 
    } 
);