NullInjectorError: No provider for MatDialog, even though I have imported it to the feature module and added it to the imports array

Question

I'm trying to create an upload feature module but I'm getting an error with MatDialog

I've already imported it in the module.ts and added it to the imports array.

upload.module.ts

import { NgModule } from '@angular/core'
import { CommonModule } from '@angular/common'
import { UploadComponent } from './upload.component'
import {
  MatButtonModule,
  MatDialogModule,
  MatListModule,
  MatProgressBarModule,
} from '@angular/material'
import { DialogComponent } from './dialog/dialog.component'
import { BrowserAnimationsModule } from '@angular/platform-browser/animations'
import { FlexLayoutModule } from '@angular/flex-layout'
import { UploadService } from './upload.service'
import { HttpClientModule } from '@angular/common/http'
import { from } from 'rxjs';

@NgModule({
  imports: [
    CommonModule,
    MatButtonModule,
    MatDialogModule,
    MatListModule,
    FlexLayoutModule,
    HttpClientModule,
    BrowserAnimationsModule,
    MatProgressBarModule

  ],
  declarations: [UploadComponent, DialogComponent],
  exports: [UploadComponent],
  entryComponents: [DialogComponent], // Add the DialogComponent as entry component
  providers: [UploadService],
})
export class UploadModule {}  

upload.component.ts

import { Component } from '@angular/core'
import { MatDialog } from '@angular/material'
import { DialogComponent } from './dialog/dialog.component'
import { UploadService } from './upload.service'

@Component({
  selector: 'app-upload',
  templateUrl: './upload.component.html',
  styleUrls: ['./upload.component.css'],
})
export class UploadComponent {
  constructor(public dialog: MatDialog, public uploadService: UploadService) {}

  public openUploadDialog() {
    let dialogRef = this.dialog.open(DialogComponent, {
      width: '50%',
      height: '50%',
    })
  }
}

edit to share upload.service.ts

import { Injectable } from '@angular/core'
import {
  HttpClient,
  HttpRequest,
  HttpEventType,
  HttpResponse,
} from '@angular/common/http'
import { Subject } from 'rxjs/Subject'
import { Observable } from 'rxjs/Observable'

const url = 'http://localhost:8000/upload'

@Injectable()
export class UploadService {
  constructor(private http: HttpClient) {}

  public upload(files: Set<File>):
  { [key: string]: { progress: Observable<number> } } {

  // this will be the our resulting map
  const status: { [key: string]: { progress: Observable<number> } } = {};

  files.forEach(file => {
    // create a new multipart-form for every file
    const formData: FormData = new FormData();
    formData.append('file', file, file.name);

    // create a http-post request and pass the form
    // tell it to report the upload progress
    const req = new HttpRequest('POST', url, formData, {
      reportProgress: true
    });

    // create a new progress-subject for every file
    const progress = new Subject<number>();

    // send the http-request and subscribe for progress-updates
    this.http.request(req).subscribe(event => {
      if (event.type === HttpEventType.UploadProgress) {

        // calculate the progress percentage
        const percentDone = Math.round(100 * event.loaded / event.total);

        // pass the percentage into the progress-stream
        progress.next(percentDone);
      } else if (event instanceof HttpResponse) {

        // Close the progress-stream if we get an answer form the API
        // The upload is complete
        progress.complete();
      }
    });

    // Save every progress-observable in a map of all observables
    status[file.name] = {
      progress: progress.asObservable()
    };
  });

  // return the map of progress.observables
  return status;
}}

Recieved this error: ERROR Error: Uncaught (in promise): NullInjectorError: StaticInjectorError(AppModule)[UploadComponent -> MatDialog]: StaticInjectorError(Platform: core)[UploadComponent -> MatDialog]: NullInjectorError: No provider for MatDialog! NullInjectorError: StaticInjectorError(AppModule)[UploadComponent -> MatDialog]: