禁用和启用对输入不起作用

Question

这是html代码

我想启用和禁用输入字段取决于布尔值。但它不起作用。

     <md-checkbox (change)="triggerSomeEvent()"  [checked]="d.checked" [(ngModel)]="d.checked" formControlName="checked" >{{d.day}}</md-checkbox>

     <input  type="time" class="custome-text-input" [(ngModel)]="d.hoursofoperationto" formControlName="hoursofoperationto" [required]="days[i].checked" [disabled]="isDisabled">

这是组件方法

isDisabled = true;
    triggerSomeEvent(): void {
    this.isDisabled = !this.isDisabled;
}