I made a directive designed to be attached to an element using the ngModel directive. If the model's value matches something the value should then set to the previous value. In my example I'm looking for "foo", and setting it back to the previous if that's what's typed in.
My unit tests passed fine on this because they're only looking at the model value. However in practice the DOM isn't updated when the "put back" triggers. Our best guess here is that setting old == new prevents a dirty check from happening. I stepped through the $setViewValue method and it appears to be doing what it ought to. However it won't update the DOM (and what you see in the browser) until I explicitly call ngModel.$render() after setting the new value. It works fine, but I just want to see if there's a more appropriate way of doing this.
Code is below, here's a fiddle with the same.
angular.module('myDirective', [])
.directive('myDirective', function () {
return {
restrict: 'A',
terminal: true,
require: "?ngModel",
link: function (scope, element, attrs, ngModel) {
scope.$watch(attrs.ngModel, function (newValue, oldValue) {
//ngModel.$setViewValue(newValue + "!");
if (newValue == "foo")
{
ngModel.$setViewValue(oldValue);
/*
I Need this render call in order to update the input box; is that OK?
My best guess is that setting new = old prevents a dirty check which would trigger $render()
*/
ngModel.$render();
}
});
}
};
});
function x($scope) {
$scope.test = 'value here';
}