How to call a function in “ng-src”

Question

I need to be able to call a function in order to run code to dynamically retrieve the source of an image. The following code snippet shows an example of what I want:

Answer 1

Wouldn't it be better to pass myFunction as an argument to the custom directive? That way, we decouple the two, and can easily change which function to pass in in the future.

HTML

JS:

angular.module('testApp', [])
.controller('TestCtrl', function($scope) {
    $scope.myFunction = function() {
        return 'http://nodejs.org/images/roadshow-promo.png';
    }
})
.directive('mySrc', function() {
    return {
        restrict: 'A',
        scope: {
            callback: '&'
        },
        link: function ( scope, elem, attrs ) {
            elem.attr('src', scope.callback());
        }
    };
})

http://jsfiddle.net/GLS2a/