Ionic - directive in modal not working

I have a modal with OpenLayers map directive, which works fine except in modal window. I tried loading with controller but nothing.

This is directive i created, as you can see it's simple as possible:

.directive('olMap', function() {
return {
    restrict: 'E',
    replace: true,
    template: '<div id="map" class="map"></div>',

    link: function postLink(scope, element, attrs) {
      var map = new ol.Map({
          target: 'map',
          layers: [
            new ol.layer.Tile({
              source: new ol.source.MapQuest({layer: 'sat'})
            })
          ],
          view: new ol.View({
            center: ol.proj.transform([37.41, 8.82], 'EPSG:4326', 'EPSG:3857'),
            zoom: 4
          })
      });
    }
}
});

Why is that?