Convert boolean value to yes/no by angular directive

Question

I need to show Boolean value to yes/no using directive. My directive is given below

 directives.directive('niBooltoYesno',
        function () {
            return {
                restrict: 'EA',
                require: 'ngModel',
                link: function (scope, element, attrs, ngModel) {
                    function formatter(value) {
                        if (value) {
                            return value === true ? 'Yes' : 'No';
                        } else {
                            return '';
                        }
                    }
                    ngModel.$formatters.push(formatter);

                }
            };
        });

<ni-boolto-yesno data-ng-model="set_unit.isActive" ></ni-boolto-yesno>

But it does not work. Please help me in this point.

Answer 1

You're not using the right tool for the job. This should be a filter:

{{ someBooleanValue | yesNo }}

The filter would be as simple as

module.filter('yesNo', function() {
    return function(input) {
        return input ? 'yes' : 'no';
    }
});

If you still choose to use a directive, you don't need ngModel and formatters, which is used on form fields that must read and write to a model. All you need is a template:

module.directive('yesNo', function() {
    return {
        template: '<span>{{ yesNo ? "yes" : "no" }}</span>',
        scope: {
            yesNo: '='
        }
    };
});

and you woud use it as

<span yes-no="someBoolean"></span>

Answer 2

I define textual values for 0 and 1 with...

{{object.PROPERTY?'Yes':'No'}}

...when presented with something like this:

{
  "PROPERTY": 0
}

The result would then be 'No'.