How to validate form with input[type=file] in angularjs

Question

HTML:

Answer 1

From the reference of NgModelController.$render()

Called when the view needs to be updated. It is expected that the user of the ng-model directive will implement this method.

You need to implement $render() to call it. You can do something like this

myApp.directive('validFile', function () {
    return {
        require: 'ngModel',
        link: function (scope, el, attrs, ngModel) {
            ngModel.$render = function () {
                ngModel.$setViewValue(el.val());
            };

            el.bind('change', function () {
                scope.$apply(function () {
                    ngModel.$render();
                });
            });
        }
    };
});

DEMO