CODEWITHSUNDEEP
angular
Lukho Mdingi
Lukho Mdingi

Reputation: 548

Angular 9 - Change Checkbox Value Based on Authentication

I have an application in Angular in which I have a checkbox that requires authentication before it changes. The idea here is as follows:

I tried using preventDefault with both the click and change events. It prevents the change, but it doesn't allow me to set it dynamically. I also tried the following:

HTML:

<div class="pull-right">
    <input id="authenticate" type="checkbox" [(ngModel)]="IsAuthenticated" (ngModelChange)="CheckForAuthentication($event)"/>
    <label class="label" for="authenticate">
         <span>Authenticate</span>
    </label>
</div>

Typescript:

@Component({
selector: 'app-authentication',
templateUrl: './authentication.component.html',
styleUrls: ['./authentication.component.scss']
})
export class AuthenticationComponent implements OnInit {
    IsAuthenticated: boolean = false;
    constructor(protected service: AuthenticationService) {}

    ngOnInit() {}

    async CheckForAuthentication(value: boolean) {
        // If we're unchecking don't do anything
        if (!value) {
            return;
        }

        // Remain false until authentication is complete
        this.IsAuthenticated = false;

        // Wait for authentication
        const authenticated = await this.service.Authenticate();

        // If authentication is true, change the checkbox
        this.IsAuthenticated = authenticated;
    }
}

Upvotes: 1

Views: 577

Answers (1)

alexortizl
alexortizl

Reputation: 2710

Checkboxes are a little tricky. You need to change its checked property

HTML 

<input id="authenticate" type="checkbox" #checkbox (change)="CheckForAuthentication(checkbox)" />

Typescript 

@Component({
    selector: 'app-authentication',
    templateUrl: './authentication.component.html',
    styleUrls: ['./authentication.component.scss']
})
export class AuthenticationComponent implements OnInit {
    constructor(protected service: AuthenticationService) { }

    private IsAuthenticated: boolean = false;

    ngOnInit() { }

    async CheckForAuthentication(checkbox: HTMLInputElement) {
        // If we're unchecking don't do anything
        if (!checkbox.checked) {
            return;
        }

        // Remain false until authentication is complete
        this.IsAuthenticated = false;
        checkbox.checked = false;

        // Wait for authentication
        const authenticated = await this.service.Authenticate();

        // If authentication is true, change the checkbox
        this.IsAuthenticated = authenticated;
        checkbox.checked = authenticated;
    }
}

I used a template variable but this can also be done with @ViewChild

Upvotes: 1

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