Angular 4 个按钮禁用图标未显示

Angular 4 button disabled icon is not showing

Console image of the inspected element

问题: 当我的按钮具有禁用属性并且我将鼠标悬停在它上面时,禁用图标没有显示。

有人可以建议我如何解决这个问题吗?

我在下面附上了一段代码:

<form (ngSubmit)='onSubmit(form)' *ngIf="!submitted" #form="ngForm"> 
    <input required #password="ngModel" [(ngModel)]="stackDefaultData.password" name="password" type="password" class="form-control"> 
    <button type="submit" [disabled]="form.invalid">Submit</button> 
</form>     

这应该有效:

<button  type="submit" disabled="!form.valid" 
  [ngStyle]="{'cursor': (!form.valid? 'not-allowed':'pointer')}">Submit</button>