My custom directive to 2 way-bind the size attribute of <select>. The issue is open here https://github.com/angular/angular.js/issues/1619

ngSize

myApp.directive('ngSize', function() {
    return {
        restrict:'A',
        scope: {
            ngSize: '='
        },
        link: function(scope, elem, attrs) {
            scope.$watch("ngSize", function(newVal, oldVal) {
                angular.element(elem).attr('size', newVal);
            });
        }
    };
});

Using an isolated scope does not work when using ng-options. Use this instead:

link: function(scope, elem, attrs) {
            scope.$watch(attrs['ngSize'], function(size) {
                angular.element(elem).attr('size', size);
            });
        }