Question

我目前面临计算属性的问题，我有一个名为crossconnection的模型，其中包含一些计算属性，如：

relevantPoints: computed(function () {

    if (this.get('IsCA') === true && this.get('IsCM') === true) {
        return "/assets/images/big/ca-cm.png";
    }
    else if (this.get('IsCA') === true && this.get('IsCM') === false) {
        return "/assets/images/big/ca.png";
    }
    else if (this.get('IsCA') === false && this.get('IsCM') === true) {
        return "/assets/images/big/cm.png";
    }
    else if (this.get('IsCA') === false && this.get('IsCM') === false) {
        return "/assets/images/big/nca-ncm.png";
    }

}),

运行项目时，我不断收到以下错误：

未捕获的TypeError：无法将类作为函数调用

请有人澄清一下吗？

PS：我正在使用，

Ember：3.0.0
Ember数据：3.0.2
jQuery：3.3.1

更新：

澄清：我有一个包含一些计算属性的模型'crossconnection'，我的模型是通过一个简单的

从控制器中调用的

from = this.store.query('crossconnection ', {
            fromOpKey: this.get('opSelected').get('opKey'),
            limit: -1
        });

然后导致以下错误（附加完整堆栈跟踪）

Uncaught TypeError: Cannot call a class as a function
    at classCallCheck (ember-babel.js:11)
    at Object.Class [as Object] (core_object.js:25)
    at Module.callback (crossconnection.js:65)
    at Module.exports (loader.js:106)
    at requireModule (loader.js:27)
    at Class._extractDefaultExport (index.js:410)
    at Class.resolveOther (index.js:110)
    at Class.superWrapper [as resolveOther] (ember-utils.js:420)
    at Class.resolve (resolver.js:133)
    at _resolve (container.js:871)
classCallCheck  @   ember-babel.js:11
Class   @   core_object.js:25
(anonymous) @   crossconnection.js:65
Module.exports  @   loader.js:106
requireModule   @   loader.js:27
_extractDefaultExport   @   index.js:410
resolveOther    @   index.js:110
superWrapper    @   ember-utils.js:420
resolve @   resolver.js:133
_resolve    @   container.js:871
resolve @   container.js:574
resolve @   container.js:578
factoryFor  @   container.js:136
factoryFor  @   container_proxy.js:40
modelFactoryFor @   -private.js:11593
_modelFactoryFor    @   -private.js:11556
_modelFor   @   -private.js:11547
modelFor    @   -private.js:11540
_query  @   -private.js:8666
_query  @   -private.js:10819
query   @   -private.js:10806
(anonymous) @   ops.js:55
applyStr    @   ember-utils.js:524
sendEvent   @   ember-metal.js:257
notifyObservers @   ember-metal.js:1103
propertyDidChange   @   ember-metal.js:886
set @   ember-metal.js:2893
set @   observable.js:104
openOpPopupWithKey  @   ops.js:143
send    @   action_handler.js:28
(anonymous) @   action.js:124
exports.flaggedInstrument   @   ember-metal.js:3920
(anonymous) @   action.js:123
_run    @   backburner.js:758
_join   @   backburner.js:736
join    @   backburner.js:477
run.join    @   ember-metal.js:4366
handler @   action.js:102
(anonymous) @   event_dispatcher.js:234
dispatch    @   jquery.js:5183
elemData.handle @   jquery.js:4991

Answer 1

请确保正确导入computed：

import { computed } from '@ember/object';

Answer 2

编辑 - 这似乎不是错误的原因，但我现在暂时将它留在这里

您在计算中缺少一个参数。 Computed首先将属性视为字符串，然后是回调函数：

relevantPoints: computed(‘isCA’, ‘isCM’, function () {

    if (this.get('IsCA') === true && this.get('IsCM') === true) {
        return "/assets/images/big/ca-cm.png";
    }
 ...,
}),

这个答案适用于1.13到3.x，对＆lt;的代码片段进行了一处小修改。 3.0。小于3.0的应用程序版本应该执行Ember.computed而不是计算。

无法将类作为函数调用

2 个答案: