无法运行角度为 10 的有角度的材料

Question

I am using angular the latest version of angular which is angular 10 and unable to import any material component. As soon as i import angular material component it start giving error.

Step to reproduce issue:

ng new app

with angular cli 10.1.0

ng add @angular/material

On importing MatButton in App.ts the error is given below:

ERROR in node_modules/@angular/material/button/button.d.ts:22:22 - error NG6002:
 Appears in the NgModule.imports of AppModule, but could not be resolved to an N
gModule class.

This likely means that the library (@angular/material/button) which declares Mat
Button has not been processed correctly by ngcc, or is not compatible with Angul
ar Ivy. Check if a newer version of the library is available, and update if so.
Also consider checking with the library's authors to see if the library is expec
ted to be compatible with Ivy.

22 export declare class MatButton extends _MatButtonMixinBase implements AfterVi
ewInit, OnDestroy, CanDisable, CanColor, CanDisableRipple, FocusableOption { 

Package.json

{
  "name": "c-m-t",
  "version": "0.0.0",
  "scripts": {
    "ng": "ng",
    "start": "ng serve",
    "build": "ng build",
    "test": "ng test",
    "lint": "ng lint",
    "e2e": "ng e2e"
  },
  "private": true,
  "dependencies": {
    "@angular/animations": "~10.1.0",
    "@angular/cdk": "^10.2.0",
    "@angular/common": "~10.1.0",
    "@angular/compiler": "~10.1.0",
    "@angular/core": "~10.1.0",
    "@angular/forms": "~10.1.0",
    "@angular/material": "^10.2.0",
    "@angular/platform-browser": "~10.1.0",
    "@angular/platform-browser-dynamic": "~10.1.0",
    "@angular/router": "~10.1.0",
    "rxjs": "~6.6.0",
    "tslib": "^2.0.0",
    "zone.js": "~0.10.2"
  },
  "devDependencies": {
    "@angular-devkit/build-angular": "~0.1001.0",
    "@angular/cli": "~10.1.0",
    "@angular/compiler-cli": "~10.1.0",
    "@types/node": "^12.11.1",
    "@types/jasmine": "~3.5.0",
    "@types/jasminewd2": "~2.0.3",
    "codelyzer": "^6.0.0",
    "jasmine-core": "~3.6.0",
    "jasmine-spec-reporter": "~5.0.0",
    "karma": "~5.0.0",
    "karma-chrome-launcher": "~3.1.0",
    "karma-coverage-istanbul-reporter": "~3.0.2",
    "karma-jasmine": "~4.0.0",
    "karma-jasmine-html-reporter": "^1.5.0",
    "protractor": "~7.0.0",
    "ts-node": "~8.3.0",
    "tslint": "~6.1.0",
    "typescript": "~4.0.2"
  }
}

App.ts

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

import { AppRoutingModule } from './app-routing.module';
import { AppComponent } from './app.component';
import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
import { MatButton } from '@angular/material/button';

@NgModule({
  declarations: [
    AppComponent
  ],
  imports: [
    BrowserModule,
    AppRoutingModule,
    BrowserAnimationsModule,
    MatButton
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }

Answer 1

The solution is in the error message (emphasis mine):

ERROR in node_modules/@angular/material/button/button.d.ts:22:22 - error NG6002: Appears in the NgModule.imports of AppModule, but could not be resolved to an NgModule class .

You need to import the module. Change your import ( import { MatButton } from '@angular/material/button'; ) to the following:

import { MatButtonModule } from '@angular/material/button';
//...
  imports: [
    //...
    MatButtonModule
  ],