Angular 2+ attr.disabled is not working for div when I try to iterate ngFor loop

Question

I'm working on a appointment booking app, where I'm displaying time slots for appointments using *ngFor to loop.

html

<div *ngFor="let item of allTimeSlots">
    <div class="col-sm-3">
        <div class="choice" data-toggle="wizard-slot" [attr.disabled]="item.status" (click)="slotSelected($event)">
            <input type="radio" name="slot" value="{{item.timeSlot}}">
            <span class="icon">{{item.timeSlot}}</span> {{item.status}}
        </div>
    </div>
</div>

typescript

for (var index = 0; index < this.totalMinutes; index += 15, i++) {
  this.allTimeSlots[i] = new allTimeSlots("", false);

  this.allTimeSlots[i].timeSlot = (hour <= 12 ? hour : hour - 12) + ":" + (minute <= 9 ? ("0" + minute) : minute) + " " + ampm;
  this.bookedTimeSlots.forEach(element => {
    if (this.allTimeSlots[i].timeSlot == element) {
      this.allTimeSlots[i].status = true;
    }
  });
}

Here's screen shot of time slots which displays true if the time slot is booked and false if available for debugging purpose.

When I run this code it doesn't throw any error but all the div elements created by *ngFor are disabled. I tried to use *ngIf instead of disabled, it works pretty well. But the problem is I want to display whether the time slot is available or not.

Answer 1

Use [disabled] instead of [attr.disabled]

This is because [attr.disabled]="false" will add disabled="false" to the element which in html, will still disable the element

Syntax that will not disable an element

<button>Not Disabled</button>
<button [disabled]="false">Not Disabled</button>

Syntax that will disable an element

<button disabled></button>
<button disabled="true"></button>
<button disabled="false"></button>
<button [attr.disabled]="true"></button>
<button [attr.disabled]="false"></button>
<button [disabled]="true"></button>

disabled will disable an element whether it is true or false, it's presence means that the element will be disabled. Angular will not add the disabled element at all for [disabled]="variable" if variable is false.

As you mentioned in your comment, you are using div elements and not buttons, which angular 2 doesn't recognise the disabled element of. I would recommend using a button if you are going to be capturing click events but if not you could do something like:

<div [ngClass]="{ 'disabled': item.status }"></div>

and have a CSS class to show the time slot as booked.

More information on [ngClass] is available in the documentation