title: Angular 2 material mat-select calling multiple times
body: <p>I am using angular material . When I use onSelectionChange, its calling multiple times when page loading or when I change the selection. Can some one please help me.</p>
  
  <pre><code> &lt;mat-form-field&gt;
     &lt;mat-select id="stateSelect" name="stateSelect" class="form-control" 
                 placeholder="State Select" [(ngModel)]="myModel.state" required&gt;
       &lt;mat-option (onSelectionChange)="updateState($event)" *ngFor="let state of stateList" [value]="state.code"&gt;
         {{ state.value }}
       &lt;/mat-option&gt;
     &lt;/mat-select&gt;
     &lt;mat-error&gt;State is required&lt;/mat-error&gt;
   &lt;/mat-form-field&gt;
  
   // In my ts file
   updateState(event: any) {
     // my code
   }
  </code></pre>
  
  <p>I have used event.isUserInput to check true for false, But still some times its entering into condition without any selection. Some one please help me on this</p>