Angular 错误：未找到MatsnakBarContainer的组件工厂

我已经开始了一个简单的AngleMaterial项目，并尝试在页面加载时显示快餐店。但它抛出了以下错误：-

错误：未找到MatSnackBarContainer的组件工厂。你加了吗 是否将其发送到@NgModule.entryComponents

我甚至在

app.module.ts

的条目组件列表中包含了AppComponent，但它不起作用

以下是我的app.component.html：-

import { Component } from '@angular/core';
import { MatSnackBar } from '@angular/material';
@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css'],
  providers: [MatSnackBar]
})
export class AppComponent {
  title = 'snackbarapp';

  constructor(public snackBar: MatSnackBar) {
    this.snackBar.open('hello', 'world', { duration: 2000 });
  }
}

以下是app.module.ts：-

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';

import { AppComponent } from './app.component';
import { MatSnackBar } from '@angular/material';
import { Overlay } from '@angular/cdk/overlay';

@NgModule({
  declarations: [AppComponent],
  imports: [BrowserModule ],
  entryComponents: [AppComponent],
  providers: [MatSnackBar, Overlay],
  bootstrap: [AppComponent]
})
export class AppModule {}

我有以下依赖项：-

 "dependencies": {
    "@angular/animations": "^6.1.10",
    "@angular/cdk": "^7.2.0",
    "@angular/common": "^6.1.0",
    "@angular/compiler": "^6.1.0",
    "@angular/core": "^6.1.0",
    "@angular/forms": "^6.1.0",
    "@angular/http": "^6.1.0",
    "@angular/material": "^7.2.0",
    "@angular/platform-browser": "^6.1.0",
    "@angular/platform-browser-dynamic": "^6.1.0",
    "@angular/router": "^6.1.0",
    "core-js": "^2.5.4",
    "rxjs": "^6.0.0",
    "zone.js": "~0.8.26"
  },
  "devDependencies": {
    "@angular-devkit/build-angular": "~0.7.0",
    "@angular/cli": "~6.1.5",
    "@angular/compiler-cli": "^6.1.0",
    "@angular/language-service": "^6.1.0",
    "@types/jasmine": "~2.8.6",
    "@types/jasminewd2": "~2.0.3",
    "@types/node": "~8.9.4",
    "codelyzer": "~4.2.1",
    "jasmine-core": "~2.99.1",
    "jasmine-spec-reporter": "~4.2.1",
    "karma": "~1.7.1",
    "karma-chrome-launcher": "~2.2.0",
    "karma-coverage-istanbul-reporter": "~2.0.0",
    "karma-jasmine": "~1.1.1",
    "karma-jasmine-html-reporter": "^0.2.2",
    "protractor": "~5.4.0",
    "ts-node": "~5.0.1",
    "tslint": "~5.9.1",
    "typescript": "~2.7.2"
  }

如何修复它？

• 在使用SnackBar模块之前，您必须在中添加app.module.ts：

• 在导入数组中添加

  matsnakbarmodule

• 您必须在

  声明

  和

  引导

  数组中添加相关组件（在其中使用snackbar组件）：

@NgModule({
声明：[
应用组件
import { MatSnackBarModule } from '@angular/material';

 @NgModule({
   declarations: [
    AppComponent  <-- here
  ],

 imports: [
   MatSnackBarModule  <-- here
 ],

  bootstrap: [
    AppComponent  <-- here
  ],
})
export class AppModule { }