Select Next Item in Datagrid

programming flash
1

Is it possible to change the focus in the Datagrid through ActionScript? Right now, I have a Datagrid with a list of external .flv’s. When the user selects one, the video begins playing. I would like to create a “next” and “last” button that will change focus on the Datagrid and play the video. Here is what I currently have to play a selected video.

function cellPress(evt_obj:Object) {
    var item = mydgrid.selectedItem;
    tt( mydgrid.selectedItem.name);
    var fName = mydgrid.selectedItem.name
    playMovie(fName);
};

function playMovie(what) {
    this.videoContainer._width = vidWidth;
    this.videoContainer._height = vidHeight;
    stopVideo();
    initNetStream();
    
    ns.setBufferTime(5);
    this.videoContainer.attachVideo(this.ns);
    ns.play(what);
}

How can I adapt this to make a playNextMovie function? Thanks for your help. I look forward to your suggestions.