Question

我正在使用Ionic2并收到此错误：

Runtime Error
Cannot read property 'prototype' of undefined

阅读here和here，它表明它可能与声明子类和基类的顺序有关。我正在使用带有子类的基类。你在哪里改变它们的声明顺序，是在进口中吗？在什么文件？

有趣的是我的代码工作正常，并且突然开始出现此错误，即使没有我更改基类或子类。我确实对另一个文件进行了更改，我现在已将其恢复，但仍然会收到错误。

更多详情：

错误：

main.js:24046Uncaught TypeError: Cannot read property 'prototype' of undefined
    at __extends (main.js:24046)
    at job.ts:26
    at Object.<anonymous> (job.ts:24)
    at __webpack_require__ (bootstrap cdd11c2…:19)
    at Object.<anonymous> (main.js:46012)
    at __webpack_require__ (bootstrap cdd11c2…:19)
    at Object.<anonymous> (personModel.ts:21)
    at __webpack_require__ (bootstrap cdd11c2…:19)
    at Object.<anonymous> (locationModel.ts:11)

代码：

job.ts

import { Component, ViewChild, ChangeDetectionStrategy, ChangeDetectorRef } from '@angular/core';
import { NavController, NavParams, InfiniteScroll, Content, Platform, Events, AlertController, LoadingController, ViewController, PopoverController } from 'ionic-angular';
import { JobModel } from '../model/jobModel';
import { PersonModel } from '../model/personModel';
import { SubCategoryModel } from '../model/subCategoryModel';
import { LocationModel } from '../model/locationModel';
import { RatingModel } from '../model/ratingModel';
import { ReviewPage } from '../review/review';
import { ChatsPage } from '../chats/chats';
import { CategoryPage } from '../category/category';
import { PersonPage } from '../person/person';
import { MyCameraPage } from '../mycamera/mycamera';
import { JobService } from '../service/jobService';
import { PersonService } from '../service/personService';
import { RatingService } from '../service/ratingService';
import { UtilityService } from '../utils/utilityService';
import { SearchJobsParent } from '../searchjobs/searchjobsParent';
import { MapRangeService } from '../service/mapRangeService';

@Component({
  selector: 'job',
  templateUrl: 'job.html',
  changeDetection: ChangeDetectionStrategy.OnPush
})

export class JobPage extends SearchJobsParent {
  @ViewChild(Content) content: Content;
.....

searchJobsParent.ts

...
@Component({
})
export class SearchJobsParent {
...

离子信息

Your system information:

Cordova CLI:  You have been opted out of telemetry. To change this, run: cordova telemetry on.
6.4.0

Ionic Framework Version: 2.0.0-rc.4
Ionic CLI Version: 2.1.18
Ionic App Lib Version: 2.1.9
Ionic App Scripts Version: 1.0.0
ios-deploy version: Not installed
ios-sim version: Not installed
OS: macOS Sierra
Node Version: v6.9.4
Xcode version: Not installed

Answer 1

我通过使用Composition而不是Inheritance来解决这个问题。

您可以在以下位置创建具有常用功能的类的实例：

<强> myClas.ts

private someCommonClass: SomeCommonClass = null;
    ...
    this.someCommonClass = new SomeCommonClass(platform, ref);

<强> someCommonClass.ts

constructor(platform: Platform)

Answer 2

第一条评论here让我思考正确并引导我找到解决方案。我的问题是我试图将一个类导入我的基类。导入的类没有按正确的顺序捆绑。通过在app.component.ts中切换我的import语句的顺序，我能够解决问题。

在app.component.ts中：

<强>错误

import { ListPage } from '../pages/list/list';
import { LoginPage } from "../pages/login/login";

这是错误的，因为ListPage扩展了导入LoginPage的AppPage（此处未列出）。

从右

import { LoginPage } from "../pages/login/login"; import { ListPage } from '../pages/list/list';

Answer 3

发生此问题是因为您安装了Native插件，此插件从IonicNativePlugin扩展为示例（Base64ToGallery，TextToSpeech，...）。所以，这引起了冲突，我终止了这个延伸，这是工作......

按照示例执行TextToSpeech插件的步骤：

YourProjectFolder\node_modules\@ionic-native\text-to-speech
打开文件index.d.ts

去申报课程：

export declare class TextToSpeech  extends IonicNativePlugin{
/**
 * This function speaks
 * @param options {string | TTSOptions} Text to speak or TTSOptions
 * @return {Promise<any>} Returns a promise that resolves when the speaking finishes
 */
speak(options: string | TTSOptions): Promise<any>;
/**
 * Stop any current TTS playback
 * @return {Promise<any>}
 */
stop(): Promise<any>;
}

删除extends IonicNativePlugin并保存。

就是这样！

Answer 4

有人尝试提供具有正确顺序的参考文件，如下所示：

/// <reference path='SomeCommonClass.ts' />
/// <reference path='TheExtendingClass.ts' />

Ionic2：运行时错误无法读取属性＆＃39;原型＆＃39;未定义的

4 个答案: