角度:工厂模型中的更新未反映在控制器中

编程入门行业动态更新时间:2024-10-25 14:31:06

本文介绍了角度:工厂模型中的更新未反映在控制器中的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！问题描述

我有一个保存用户首选项值的用户首选项工厂.页面加载时为空.用户登录后，将用用户个人资料填充. 伪代码

I have a user preference factory that holds user preference values. When the page loads it is empty. After user logs in it is filled up with user profile. pseudo code

app.factory('pref', function($rootScope){ var pref = {}, age, name; $rootScope.$on('logged.in', function(){ pref.name = 'sam'; pref.age = 30; pref.currency = '$'; age = getAge(); name = getName(); }) function getName(){ //format name return name; } function getAge(){ return age; } return { currency: pref.currency, age: age, name: name } })

然后我将工厂注入控制器中:

Then I inject the factory in my controller:

app.controller('MainCtrl', function($scope, pref) { $scope.name = pref.name; //Return undefined var currency = pref.currency; $scope.price = function(amount){ return amount + currency; //don't show $ sign } });

首选工厂中的返回值未在控制器中更新.我该如何运作?

Return value from pref factory not updating in controller. How do I make it work?

plunkr plnkr.co/edit/SKJC5hUPEm72JqGJyT9y

推荐答案

从pref工厂返回的对象，

{ setPreference: setPreference, currency: pref.currency, name: pref.name, formatTime: formatTime }

将currency和name分配给未定义的属性.由于undefined不是引用类型，因此currency和name不会看到"对象pref的任何更新.

assigns currency and name to undefined properties. Since undefined is not a reference type, currency and name will not "see" any updates to object pref.

我建议将引用pref对象的属性作为工厂返回的对象的一部分:

I suggest instead that a property that references the pref object be part of the object returned by the factory:

{ setPreference: setPreference, prefs: pref, formatTime: formatTime }

现在，我们对pref所做的任何更新都将反映在prefs中.在您的控制器中，请参考该对象的属性，如下所示:

Now, any updates we make to pref will be reflected in prefs. Refer to properties of that object as follows in your controller:

console.log(prefService.prefs.name)

为了不更改pref指向的引用，请使用angular.copy()修改pref引用的对象:

In order to not change the reference that pref points to, use angular.copy() to modify the object that pref references:

function setPreference(values){ //pref = values; <<-- won't work, since pref will now reference another object angular.copy(values,pref); }

更新:要使视图在name更改时自动更新，建议将对prefs的引用保存为范围属性:

Update: to have the view automatically update when the name changes, I suggest saving a reference to prefs as a scope property:

$scope.prefs = prefService.prefs;