How to dynamically change input value

Question

I\'m trying to show some editable results to the users, so I show them through an input field. This is a basic example of what I\'m doing:

Answer 1

What do you want to happen when the user edits the results input? Do you want the data binding to break (I assume not and ignore this possibility)? Do you want one of the inputs to adjust to the proper value?

If you only want to display the output, do this, in your controller:

$scope.result = function() { return $scope.first + $scope.second; }

And in your view:

{{ result() }}

But if you want the user to be able to edit the result and (let's say) have second be assigned (result - first), then you'd want something like this in your view (by the way, note the type="number"):

And in your controller:

$scope.adjustResult = function() {
  $scope.result = $scope.first + $scope.second;
};
$scope.adjustResult(); // initialize result

$scope.adjustInput = function() {
  $scope.second = $scope.result - $scope.first;
}