Ionic2:运行时错误无法读取属性'；原型&x27；未定义的

我使用的是Ionic2，出现以下错误：

阅读和分析，它表明它可能与子类和基类的声明顺序有关。我将基类与子类一起使用。您在哪里更改它们的申报顺序，是在进口中吗？在什么档案里

有趣的是，我的代码工作得很好，突然出现了这个错误，即使我没有更改基类或子类。我确实对另一个文件进行了更改，现在已恢复，但仍然出现错误

更多详情：

错误：

searchJobsParent.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;
.....

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

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

constructor(platform: Platform)

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

---

我通过使用组合而不是继承来解决这个问题

您可以创建具有通用功能的类的实例：

myClas.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;
.....

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

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

constructor(platform: Platform)

someCommonClass.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;
.....

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

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

constructor(platform: Platform)

第一句话让我想到了正确的答案。我的问题是我试图将一个类导入基类。导入的类没有按正确的顺序绑定。通过切换app.component.ts中导入语句的顺序，我能够解决这个问题

在app.component.ts中：

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AppPage（此处未列出），它导入了LoginPage

对

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

---

发生此问题的原因是您安装了本机插件，并且此插件扩展自IonicNativePlugin（例如Base64ToGallery、TextToSpeech等）。所以，这导致了冲突，我移动了这个扩展，这是工作

例如，按照以下步骤创建TextToSpeech插件：

在此路径中

YourProjectFolder\node\u modules\@ionic native\text-to-speech

打开文件

index.d.ts

进入课堂声明：

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>;
}

export declare class TextToSpeech扩展了IonicNativePlugin{
/**
*此函数说明
*@param options{string | TTSOptions}要讲话的文本或TTSOptions
*@return{Promise}返回一个承诺，该承诺在讲话结束时解析
*/
说话（选项：string | TTSOptions）：承诺；
/**
*停止任何当前的TTS播放
*@return{Promise}
*/
停止：承诺；
}

删除

扩展IonicNativePlugin

并保存

---

就这些

是否有人试图提供一个顺序正确的参考文件，如下所示：

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

//
/// 

如果扩展基类，则会出现错误。如果我不扩展它，那么错误就会消失。那么你应该如何扩展对象呢？我想，这只是一个解决办法，但我们应该找到在typescript中使用抽象的方法…我有同样的问题，但我不喜欢使用typescript抽象的方法。你能告诉我你是如何解决这个问题的吗？可能是小代码段？不要使用

扩展SomeClass

。而是导入

SomeClass

并调用

this.SomeClass.someFunction（）

我需要将它注入

子类的
构造函数中吗？