unable to push value in an Array in ionic : i am trying to push a value into an array but i am getting error 

 **Cannot read property 'push' of undefined**

my html code is

     <ion-item *ngFor="let item of items"  (click)="clicked(item.title)">
                     {{item.title}}
                     </ion-item>
                    </ion-list>

and my ts code is

      clicked(item){
    
        this.addedtags.push(item);
        console.log(this.addedtags);     
      }