How to expose behavior from a directive with isolated scope?

You can do this with an isolated scope by setting up a variable in the scope that’s two-way bound to the controller (using ‘=’). In your directive you can then assign the function to that variable, and angular will use the binding to find the corresponding variable in your controller. That variable will point to a function that your controller can call.

http://jsfiddle.net/GWCCr/

html: Note the new attrib:

<div ng-app="main">
    <div ng-controller="MyCtrl">
        <button ng-click="call()" >Call</button>
        <div id="container" my-directive my-fn="fnInCtrl"> </div>
    </div>
</div>

js:

angular.module("main", []).controller("MyCtrl", function($scope) {
    $scope.call = function() {
        $scope.fnInCtrl();
    };
}).directive("myDirective", function() {
    return {
        scope: {
            myFn: '='
        },
        controller: function($scope) {
            $scope.myFn = function() {
                console.log("myfn called");
            }
        }
    };
});