animations: [
trigger('listAnimation', [
transition('* => *', [ // each time the binding value changes
query(':leave', [
stagger(1000, [
animate('1s', style({ opacity: 0 }))
])
], { optional: true }),
query(':enter', [
style({ opacity: 0 }),
stagger(1000, [
animate('1s', style({ opacity: 1 }))
])
], { optional: true })
])
])