AngularJS: How do I manually set input to $valid in controller?

You cannot directly change a form's validity. If all the descendant inputs are valid, the form is valid, if not, then it is not.

What you should do is to set the validity of the input element. Like so;

addItem.capabilities.$setValidity("youAreFat", false);

Now the input (and so the form) is invalid. You can also see which error causes invalidation.

addItem.capabilities.errors.youAreFat == true;

I came across this post w/a similar issue. My fix was to add a hidden field to hold my invalid state for me.

<input type="hidden" ng-model="vm.application.isValid" required="" />

In my case I had a nullable bool which a person had to select one of two different buttons. if they answer yes, an entity is added to the collection and the state of the button changes. Until all of the questions get answered, (one of the buttons in each of the pairs has a click) the form is not valid.

vm.hasHighSchool = function (attended) { 
  vm.application.hasHighSchool = attended;
  applicationSvc.addSchool(attended, 1, vm.application);
}

<input type="hidden" ng-model="vm.application.hasHighSchool" required="" />
<div class="row">
  <div class="col-lg-3"><label>Did You Attend High School?</label><label class="required" ng-hide="vm.application.hasHighSchool != undefined">*</label></div>
  <div class="col-lg-2">
    <button value="Yes" title="Yes" ng-click="vm.hasHighSchool(true)" class="btn btn-default" ng-class="{'btn-success': vm.application.hasHighSchool == true}">Yes</button>
    <button value="No" title="No" ng-click="vm.hasHighSchool(false)" class="btn btn-default" ng-class="{'btn-success':  vm.application.hasHighSchool == false}">No</button>
  </div>
</div>

The answers above didn't help me solve my problem. After a long search I bumped into this partial solution.

I've finally solved my problem with this code to set the input field manually to ng-invalid (to set to ng-valid set it to 'true'):

$scope.myForm.inputName.$setValidity('required', false);

It is very simple. For example : in you JS controller use this:

$scope.inputngmodel.$valid = false;

or

$scope.inputngmodel.$invalid = true;

or

$scope.formname.inputngmodel.$valid = false;

or

$scope.formname.inputngmodel.$invalid = true;

All works for me for different requirement. Hit up if this solve your problem.