function expandTile(tileID) {
    $('tile-content-' + tileID).toggle();
    
    if($('tile-content-' + tileID).visible()==true) {
        $('tile-expander-' + tileID).setStyle({ backgroundImage: 'url(/themes/atferdssenteret/images/collapse.png)'});
    }
    else {
        $('tile-expander-' + tileID).setStyle({ backgroundImage: 'url(/themes/atferdssenteret/images/expand.png)'});
    }

}