Required attribute Not working with File input in Angular Js

I have a file upload control in my form.I am using Angular JS . When I put the required attribute to validate that the file is selected it is not working.

<input id="userUpload" name="userUpload" required type="file" accept="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" />

<button type="submit" class="btn btn-primary"><i class="icon-white icon-ok"></i>&nbsp;Ok</button>

Can you please suggest why the required is not working ?

Solution 1:

It's the ngModelController that does the validation in Angular based on attributes like require. However, currently there is no support for input type="file" with the ng-model service. To get it working you could create a directive like this:

app.directive('validFile',function(){
  return {
    require:'ngModel',
    link:function(scope,el,attrs,ngModel){
      //change event is fired when file is selected
      el.bind('change',function(){
        scope.$apply(function(){
          ngModel.$setViewValue(el.val());
          ngModel.$render();
        });
      });
    }
  }
});

Example markup:

  <div ng-form="myForm">
    <input id="userUpload" ng-model="filename" valid-file name="userUpload" required type="file" accept="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" />
    <button ng-disabled="myForm.$invalid" type="submit" class="btn btn-primary"><i class="icon-white icon-ok"></i>&nbsp;Ok</button>
    <p>
      Input is valid: {{myForm.userUpload.$valid}}
      <br>Selected file: {{filename}}
    </p>
  </div>

Check out my working plnkr example.

Solution 2:

Extending @joakimbl code I will suggest the direct like this

.directive('validFile',function(){
    return {
        require:'ngModel',
        link:function(scope,el,attrs,ctrl){
            ctrl.$setValidity('validFile', el.val() != '');
            //change event is fired when file is selected
            el.bind('change',function(){
                ctrl.$setValidity('validFile', el.val() != '');
                scope.$apply(function(){
                    ctrl.$setViewValue(el.val());
                    ctrl.$render();
                });
            });
        }
    }
})

and in html you can use like this

<input type="file" name="myFile" ng-model="myFile" valid-file />
<label ng-show="myForm.myFile.$error.validFile">File is required</label>