title: Expression has changed after it was checked - angular
body: <p>When I call a service in (change) action method , I got this error : </p>
  
  <blockquote>
    <p>ERROR Error: ExpressionChangedAfterItHasBeenCheckedError: Expression
    has changed after it was checked. Previous value: 'ng-untouched:
    true'. Current value: 'ng-untouched: false'</p>
  </blockquote>
  
  <p>My code : </p>
  
  <pre><code>onChange(event) { 
  
    const messageToDisplay = "Message test";
    this.popinService.open(messageToDisplay).subscribe((result: ConfirmPopinResultType) =&gt; {
      if (result === ConfirmPopinResultType.CONFIRM) {
        console.log("test");
      }
    });        
  }
  </code></pre>
  
  <p>onChange is an event handler on an input reactive form  (select dropdown list) </p>
  
  <pre><code>&lt;form [formGroup]="poolForm"&gt; 
    &lt;select id="pool-select" #item (change)="item.value = onChangePool(item.value)" formControlName="item"&gt; 
       &lt;option *ngFor="let item of items" [value]="item.name"&gt;{{ item.name }}&lt;/option&gt; 
    &lt;/select&gt; 
  &lt;/form&gt; 
  </code></pre>
  
  <p>The exception error occurs when I call the poppin service on Change event handler (that display a pop up with two button Confirm and Cancel) </p>
  
  <p>thank for your help! </p>