<div>
  <div>
    <div *ngFor="let user of users">
      <button
        class="btn"
        [@buttonState]="user.active"
        (click)="user.changeButtonState()">{{user.firstName}}</button>
    </div>
  </div>
</div>

import {Component, trigger, state, transition, animate, style} from '@angular/core';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styles: [`
     .btn {
      height: 30px;
      width: 100px;
      border: 1px solid rgba(0, 0, 0, 0.33);
      border-radius: 3px;
      margin-bottom: 5px;
     }

  `],
  animations: [
    trigger('buttonState', [
      state('true', style({
        background: '#04b104',
        transform: 'scale(1)'
      })),
      state('false',   style({
        background: '#e40202',
        transform: 'scale(1.1)'
      })),
      transition('true => false', animate('100ms ease-in')),
      transition('false => true', animate('100ms ease-out'))
    ])
  ]
})
export class AppComponent {
  users : Array<User> = [];
  constructor(){
    this.users.push(new User('Narco', false));
    this.users.push(new User('Bombasto',false));
    this.users.push(new User('Celeritas', false));
    this.users.push(new User('Magneta', false));
  }
}


export class User {
  firstName : string;
  active : boolean;

  changeButtonState(){
    this.active = !this.active;
  }
  constructor(_firstName :string, _active : boolean){
    this.firstName = _firstName;
    this.active = _active;
  }

}