只有这三种事件才会导致Angular视图的更新，都是异步事件。

Events：如 click, change, input, submit 等用户事件

XMLHttpRequests：比如从远端服务获取数据

Timers： 比如 JavaScript 的自有 API setTimeout(), setInterval()

https://angular.io/guide/lifecycle-hooks

完整源代码：export class BankAccount implements OnChanges{

 ngOnChanges(changes: SimpleChanges): void {

   debugger;

 }

 // This property is bound using its original name.

 @Input()  

 bankName: string;

 // this property value is bound to a different property name

 // when this component is instantiated in a template.

 @Input('account-id')  

 

 id: string;

 // this property is not bound, and is not automatically updated by Angular

 normalizedBankName: string;

}

@Component({

 selector: 'app',

 template: `

   

 `

})

export class App implements OnInit, AfterViewInit{

 _bankName = 'Jerry';

 ngAfterViewInit(): void {

   this._bankName = 'Jerry2';

 }

 get bankName(){

   debugger;

   return this._bankName;

 }

 ngOnInit(): void {

   debugger;

 }

}父组件的bankName，在OnInit和OnAfterViewInit时都会变化，这也会触发子组件的ngOnChange接口：