function addChannel(id) {
  var url = '/tv/tv-guide/add-channel.php?type=json&id='+escape(id)+'&callback=?';
  $.getJSON(url,function(data) {
    if(data.error) {
      showAlert(data.error);
    } else if(data.message) {
      showAlert(data.message);
    }
  });
}