How can I hide video if the link info is null?

Hi,

I set like the following, but I can not hide the video area. how can I solve this?
serverconnect1.data.query_event_info[0].rulesvideolink is null now.

<video is="dmx-video" id="video1" width="100%" dmx-show="serverconnect1.data.query_event_info[0].rulesvideolink.contains(&quot;http&quot;)"></video>