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Question

I'm trying to create a directive wrapper for the ng-minlength and ng-maxlength directives. The purpose of these wrapper directives is to populate the input model with the max and min lengths to be able to create custom validation messages. My directive looks like this

var directive = angular.module('selfservice.directives', []).directive
directive('minlength', [function() {
    return {
        restrict: 'A',
        require: 'ngModel',
        compile: function compile(tElement, tAttrs, transclude) {
            return {
                pre: function preLink(scope, elem, attrs) {
                    scope.minlength = attrs['minlength'];
                    elem.attr('ng-minlength', scope.minlength);
                    elem.removeAttr('minlength');
                }
            }
        }
    }
}])

It all compiles correctly with the ng-minlength attribute added, however the ng-minlength directive does not seem to be affecting the field validity in the usual way. I added the function to the precompile specifically so that it would compile all together in the regular digest cycle as if it had been there from the beginning, but that does not seem to be working. Can someone help me understand how to accomplish this?

Answer 1

As noted above:

I did get this to work BY adding the compile service to the post link function

Only recompile if the ng- directive wasn't there and you added it, as well as set up an attrs.$observe('minLength') to update the ng-minlength attribute when the value changes.