Bootstrap Checkbox Angular 1.5 Typescript

bootstrap-checkbox.ts

export class Checkbox implements ng.IComponentOptions {
    public bindings: any = {
        ngModel: "=",
        defaultValue: "<",
        label: "<"
    };

    public template: string = `
        <div type="button"
                class="btn btn-default"
                ng-init="$ctrl.ngModel = false"
                ng-click="$ctrl.ngModel = !$ctrl.ngModel">
                <span ng-class="{
                    'glyphicon glyphicon-check': $ctrl.ngModel,
                    'glyphicon glyphicon-unchecked': !$ctrl.ngModel,
                }"></span>
                {{::$ctrl.label}}
        </div>`;
}