Can’t resolve all parameters for AuthenticationService: ([object Object],?,[object Object])

我已经检查了几乎每个主题,并尝试了多种方法来解决它,但仍然无法在第二天击败它.

我试图像这样在appService中注入第一个authService但是得到了同样的错误

@Inject(forwardRef(() => AuthenticationService)) public authService: AuthenticationService

我检查了所有DI和服务内部的导入顺序,在我看来一切都是正确的

如果有人可以帮我处理它,我很感激.

Angular 4.0.0

AuthService

import { Injectable } from '@angular/core';
import {Http,Headers,Response} from '@angular/http';
import 'rxjs/add/operator/toPromise';
import {Observable} from 'rxjs/Rx';

import {AppServices} from "../../app.services";
import {Router} from "@angular/router";

@Injectable()
export class AuthenticationService {
  public token: any;

  constructor(
    private http: Http,private appService: AppServices,private router: Router
  ) {
    this.token = localStorage.getItem('token');
  }

  login(username: string,password: string): Observable<boolean> {
    let headers = new Headers();
    let body = null;
    headers.append("Authorization",("Basic " + btoa(username + ':' + password)));

    return this.http.post(this.appService.api + '/login',body,{headers: headers})
      .map((response: Response) => {
        let token = response.json() && response.json().token;
        if (token) {
          this.token = token;
          localStorage.setItem('Conform_token',token);
          return true;
        } else {
          return false;
        }
      });
  }

  logout(): void {
    this.token = null;
    localStorage.removeItem('Conform_token');
    this.router.navigate(['/login']);
  }
}

应用服务

import {Injectable} from '@angular/core';
import {Headers,Http,RequestOptions} from '@angular/http';
import {Router} from "@angular/router";
import {AuthenticationService} from "./auth/auth.service";

import 'rxjs/add/operator/toPromise';
import {Observable} from 'rxjs/Rx';

@Injectable()

export class AppServices {

  api = '//endpoint/';

  public options: any;
  constructor(
    private http: Http,private router: Router,public authService: AuthenticationService // doesn't work
  //  @Inject(forwardRef(() => AuthenticationService)) public authService: AuthenticationService // doesn't work either
      ) {
        let head = new Headers({
      'Authorization': 'Bearer ' + this.authService.token,"Content-Type": "application/json; charset=utf8"
    });
    this.options = new RequestOptions({headers: head});
  }

  // ====================
  //    data services
  // ====================

  getData(): Promise<any> {
    return this.http
      .get(this.api + "/data",this.options)
      .toPromise()
      .then(response => response.json() as Array<Object>)
      .catch((err)=>{this.handleError(err);})
  }

应用模块

import { browserModule } from '@angular/platform-browser';
import { browserAnimationsModule } from '@angular/platform-browser/animations';

import { NgModule } from '@angular/core';
import { FormsModule } from '@angular/forms';
import {BaseRequestOptions,HttpModule} from '@angular/http';

import { MaterialModule} from '@angular/material';
import {FlexLayoutModule} from "@angular/flex-layout";
import 'hammerjs';

import { routing,appRoutingProviders }  from './app.routing';
import { AppServices } from './app.services';
import {AuthGuard} from "./auth/auth.guard";
import {AuthenticationService} from "./auth/auth.service";

import {AppComponent} from './app.component';
import {AuthComponent} from './auth/auth.component';
import {NotFoundComponent} from './404/not-found.component';
import { HomeComponent } from './home/home.component';

@NgModule({
  declarations: [
    AppComponent,AuthComponent,NotFoundComponent,HomeComponent
  ],imports: [
    browserModule,browserAnimationsModule,FormsModule,HttpModule,routing,MaterialModule,FlexLayoutModule
  ],providers: [AppServices,AuthGuard,AuthenticationService],bootstrap: [AppComponent]
})
export class AppModule { }

你可以使用

export class AuthenticationService {
  public token: any;
  appService: AppServices;
  constructor(
    private http: Http,// private appService: AppServices,injector:Injector;
    private router: Router
  ) {
    setTimeout(() => this.appService = injector.get(AppServices));
    this.token = localStorage.getItem('token');
  }

另见DI with cyclic dependency with custom HTTP and ConfigService

要避免使用setTimeout,您还可以从AppService的构造函数中设置AuthenticationService.appService(或者相反)

虽然它不直接编译到Objective-C,但它声称生成与Objective-C相同的二进制代码

Eero compiles down to the same binary code as Objective-C

Eero offers excellent,nearly seamless interoperability with
Objective-C,C,and C++.

我发现这种方法非常有趣,我想知道是否有类似的编程语言和项目提供与Objective-C和iOS的大腿集成.
我正在为Objective-C寻找类似Coffeescript的东西.

它确实需要记录在一个更明显的地方……

但是,Mountain Lion之前的ObjC运行时库的版本没有实现NSObject类(它们没有NSObject.mm文件,例如你可以在Mac OS X 10.7’s Objective-C runtime library source code看到).

那么这是否真的意味着NSObject类现在是Objective-C运行时库的一部分而不是Foundation库组件？如果是,为什么？在继承NSObject时,是否要避免连接整个Foundation库(使用-framework Foundation)？

如果你在libobjc上运行它,你会发现NSObject实际上是由libobjc提供的：

% nm /usr/lib/libobjc.dylib | grep -F NSObject
⋮
0000000000021688 t +[NSObject _isDeallocating]
0000000000021674 t +[NSObject _tryRetain]
0000000000021780 t +[NSObject allocWithZone:]
000000000002176e t +[NSObject alloc]
0000000000021699 t +[NSObject allowsWeakReference]
0000000000021712 t +[NSObject autorelease]
0000000000020fa6 t +[NSObject class]
000000000002115a t +[NSObject conformsToProtocol:]
00000000000217ea t +[NSObject copyWithZone:]
00000000000217e6 t +[NSObject copy]
000000000002178d t +[NSObject dealloc]
⋮

(“t”表示符号由此库提供;“u”表示符号未定义,表示此库使用它,但它必须来自其他位置.)

这不是他们第一次提出NSObject的实施;在Lion中,你会在CoreFoundation.framework中找到它.

我不知道为什么他们动了它.无论如何,它是一个实现细节;正式,NSObject is still part of Foundation.