angular - Angual 6 イベントエミッタ - 動作しません

Question

誰でもこのコードの何が問題なのかを見つけてください。イベントを appcomponent に戻せません

test1.component.html

<input type="text" [(ngModel)]="mytext1" >
<button 
  id="clicked" 
  name="Click Me" 
  class="button"  
  (click)="returnData();">
  Click Me! 
</button>

test1.component.ts

import {
  Component,
  OnInit,
  Input,
  Output,
  EventEmitter
} from '@angular/core';
@Component({
  selector: 'app-test1',
  templateUrl: './test1.component.html',
  styleUrls: ['./test1.component.css']
})
export class Test1Component implements OnInit {
  constructor() {}
  @Input() mytext1: string;
  @Output() dataEmit: EventEmitter < string > = new EventEmitter < string > ();;

  ngOnInit() {}

  changeText1($event) {
    this.mytext1 = $event;
  }

  returnData() {
    console.log("button clicked");
    this.dataEmit.emit(this.mytext1);
  }

}

app.component.html

<div style="text-align:center">
  <h1>
    Welcome to {{ title }}!
  </h1>
  <app-test1 [mytext1]="childmessage" (returnData)="getTest1Data($event)"></app-test1>
  {{testText2}}
</div>

app.component.ts

import {
  Component,
  Input,
  OnInit
} from '@angular/core';
@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent implements OnInit {
  title = 'AngularDemo';
  public testText2: string = "from parent";
  childmessage: string = "I am passed from Parent to child component";

  getToggle($event) {
    this.testText2 = $event;
  }

  ngOnInit() {

  }
}

app.component.ts で応答が得られず、デバッガも得られません。