ionic slide box dynamic height - fixes the issue where the slide boxes aren't taking up the full height of the device

directive.js

app.directive('dynamicHeight', function() {
    return {
        require: ['^ionSlideBox'],
        link: function(scope, elem, attrs, slider) {
            scope.$watch(function() {
                return slider[0].__slider.selected();
            }, function(val) {
                //getting the heigh of the container that has the height of the viewport
                var newHeight = window.getComputedStyle(elem.parent()[0], null).getPropertyValue("height");
                if (newHeight) {
                    elem.find('ion-scroll')[0].style.height = newHeight;
                }
            });
        }
    };
})

view.html

<ion-slide-box>

    <ion-slide class="slide" dynamic-height>
        <ion-scroll>
            <div class="slide-box box">
              <!-- your stuff -->
            </div>
        </ion-scroll>
    </ion-slide>

</ion-slide-box>

It haven't work for me, because the height of elm.parent was 0px.
If anyone have the same problem -> I have fixed it by get the height of the ion-content tag. https://gist.github.com/eicu/db0d1464b2fd404f3882