always got 'Cannot read property 'selector' of null' error in ionic4 project, even new project about ng-zorro-antd-mobile HOT 2 CLOSED

http://ng.mobile.ant.design/#/components/toast/zh

import { Component } from '@angular/core';
import { Toast } from 'ng-zorro-antd-mobile';
@Component({
  selector: 'demo-toast-basic',
  template: `
  `,
  providers: [Toast]  // you lost
})

export class DemoToastBasicComponent {
  constructor(private _toast: Toast) {}  // you lost
}

app.module.ts sholud add entryComponents

entryComponents: [ToastComponent]

from ng-zorro-antd-mobile.

http://ng.mobile.ant.design/#/components/toast/zh

import { Component } from '@angular/core';
import { Toast } from 'ng-zorro-antd-mobile';
@Component({
  selector: 'demo-toast-basic',
  template: `
  `,
  providers: [Toast]  // you lost
})

export class DemoToastBasicComponent {
  constructor(private _toast: Toast) {}  // you lost
}

app.module.ts sholud add entryComponents

entryComponents: [ToastComponent]

Thanks!

from ng-zorro-antd-mobile.