angular2:注入到组件服务不appInject工作 [英] angular2: Inject a service to component not working with appInject
问题描述
我在谷歌之后的 angular2快速启动(无Github上的这些例子?!)
一切都顺利工作,直到是时候注入一个服务(我创建的)。
这是我的code:
进口{组件,视图,引导,NgFor}从'angular2 / angular2';\r
\r
类FriendsService {\r
名称:数组<字符串取代;\r
\r
构造函数(){\r
this.names = ['阿维亚德','陈','亚登'];\r
}\r
}\r
\r
@零件({\r
选择:'显示',\r
appInjector:[FriendsService]\r
})\r
@视图({\r
模板:\r
< P>我的名字:{{} MYNAME}< / P>\r
< P>朋友:其中,P>\r
< UL>\r
<李·纳克换=名称#名称>\r
\t\t\t{{名称}}\r
< /李>\r
< / UL>\r
,\r
指令:[NgFor]\r
})\r
\r
出口缺省类DisplayComponent {\r
MYNAME:字符串;\r
名称:数组<字符串取代;\r
\r
构造函数(friendsService:FriendsService){\r
this.myName ='爱丽丝';\r
this.names = friendsService.names;\r
}\r
}
\r
我遇到了很多例外情况,但第一个,我认为是最相关的是:
异常:无提供商FriendsService! (DisplayComponent - > FriendsService)
angular2.dev.js:22367堆栈跟踪:
angular2.dev.js:22367错误:DI异常 在NoBindingError.BaseException(angular2.dev.js:7735)
在NoBindingError.AbstractBindingError(angular2.dev.js:9029)
在新NoBindingError(angular2.dev.js:9052)
在Injector.execute._proto._throwOrNull(angular2.dev.js:27552)
在Injector.execute._proto._getByKeyDefault(angular2.dev.js:27597)
在Injector.execute._proto._getByKey(angular2.dev.js:27545)
在Injector.execute._proto._getByDependency(angular2.dev.js:27533)
在Injector.execute._proto._instantiate(angular2.dev.js:27430)
在Injector.execute._proto._new(angular2.dev.js:27403)
在InjectorInlineStrategy.execute.protoStrategy.instantiateBinding(angular2.dev.js:27192)
angular2.dev.js:22367错误上下文:
一件事,可能是相关的是,<显示>
组件是一个指令的<我的应用>
组件:
进口{组件,查看,引导}从'angular2 / angular2';\r
从./show-properties'进口DisplayComponent;\r
\r
@零件({\r
选择:我的应用\r
})\r
@视图({\r
模板:<显示>,\r
指令:[DisplayComponent]\r
})\r
类AppComponent {}\r
\r
引导(AppComponent);
\r
被这个苦苦挣扎了一段时间,似乎无法找到任何相关的答案,大量的问题,这已经在这里。
这奏效了:
@Component({
选择:'显示',
绑定:[FriendsService] //而非appInjector
})
当别的保持与上述相同。
反正根据的changelog 这是一个重大更改(感谢杰西好):
重大更改
在appInjector属性已被删除。相反,使用 viewInjector 或 hostInjector
我猜测,Angular2快速入门指南是不是最新的,因为我以为。
块引用>I'm following google's angular2 quick start (no Github for these examples?!)
Everything was working smoothly until it was time to inject a service (which I created).
This is my code:
import {Component, View, bootstrap, NgFor} from 'angular2/angular2'; class FriendsService { names: Array<string>; constructor(){ this.names = ['Aviad', 'Chen', 'Yarden']; } } @Component({ selector: 'display', appInjector: [FriendsService] }) @View({ template: <p>My name: {{ myName }}</p> <p>Friends:<p> <ul> <li *ng-for="#name of names"> {{name}} </li> </ul> , directives: [NgFor] }) export default class DisplayComponent { myName: string; names: Array<string>; constructor(friendsService: FriendsService){ this.myName = 'Alice'; this.names = friendsService.names; } }
I ran into a lot of exceptions but the first one and what I think is the most relevant is:
EXCEPTION: No provider for FriendsService! (DisplayComponent -> FriendsService) angular2.dev.js:22367 STACKTRACE: angular2.dev.js:22367 Error: DI Exception at NoBindingError.BaseException (angular2.dev.js:7735) at NoBindingError.AbstractBindingError (angular2.dev.js:9029) at new NoBindingError (angular2.dev.js:9052) at Injector.execute._proto._throwOrNull (angular2.dev.js:27552) at Injector.execute._proto._getByKeyDefault (angular2.dev.js:27597) at Injector.execute._proto._getByKey (angular2.dev.js:27545) at Injector.execute._proto._getByDependency (angular2.dev.js:27533) at Injector.execute._proto._instantiate (angular2.dev.js:27430) at Injector.execute._proto._new (angular2.dev.js:27403) at InjectorInlineStrategy.execute.protoStrategy.instantiateBinding (angular2.dev.js:27192) angular2.dev.js:22367 ERROR CONTEXT:
One thing that may be relevant is that the
<display>
component is a directive of the<my-app>
component:import {Component, View, bootstrap} from 'angular2/angular2'; import DisplayComponent from './show-properties'; @Component({ selector: 'my-app' }) @View({ template: '<display>', directives: [DisplayComponent] }) class AppComponent { } bootstrap(AppComponent);
Been struggling with this for some time and can't seem to find any relevant answer to the plenty of questions that already here.
解决方案This did the trick:
@Component({ selector: 'display', bindings: [FriendsService] // instead of appInjector })
When anything else remained the same as above.
Anyway according to the changelog this was a breaking change (thanks jesse Good):
BREAKING CHANGES
THe appInjector property has been removed. Instead use viewInjector or hostInjector.
I guess that the Angular2 Quick Start guide is not as up to date as I thought.
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