angular2 http拦截器和注入SlimLoadingBarService不起作用？

Question

我写一个http intercpetor，它是这样的：

import { Injectable, Inject } from '@angular/core'; 
import { SlimLoadingBarService } from 'ng2-slim-loading-bar'; 
// ... other imports in here 

@Injectable() 
export class HttpInterceptorService extends Http { 
    private apiEndpoint: string; 

    constructor(
     @Inject(CONFIG_TOKEN) config: Config, 
     private backend: ConnectionBackend, 
     private defaultOptions: RequestOptions, 
     private slimLoadingBarService: SlimLoadingBarService 
    ) { 
     super(backend, defaultOptions); 
     this.apiEndpoint = config.apiEndpoint; 
    } 

    get(url: string, options?: RequestOptionsArgs): Observable<any> { 
     this.beforeRequest(); 
     return super.get(this.getFullUrl(url), this.requestOptions(options)) 
      // ... 
    } 

    private beforeRequest(): void { 
     // this is not work 
     this.slimLoadingBarService.start(); 
    } 

    // ... other methods 
} 

我app.module提供的配置是这样的：

{ 
    provide: HttpInterceptorService, 
    useFactory: (backend: XHRBackend, defaultOptions: RequestOptions) => { 
     return new HttpInterceptorService(CONFIG, backend, 
      defaultOptions, new SlimLoadingBarService); 
    }, 
    deps: [XHRBackend, RequestOptions] 
} 

现在，此HTTP拦截器是工人，但SlimLoadingBarService doew不行。

我觉得应该是错的，通过new SlimLoadingBarService的领先，但直接传输SlimLoadingBarService，同样会给出，现在卡在这个地方不知道该怎么继续。

没有错误信息，但加载栏（SlimLoadingBarService）没有显示。

Answer 1

试试这个。

{ 
    provide: HttpInterceptorService, 
    useFactory: (backend: XHRBackend, defaultOptions: RequestOptions, slimLoadingBarService: SlimLoadingBarService) => { 
    return new HttpInterceptorService(CONFIG, backend, 
     defaultOptions, slimLoadingBarService); 
    }, 
    deps: [XHRBackend, RequestOptions, SlimLoadingBarService] 
}