function closeAll ()

// create a new instance of the WindowHost control
var host = new ui.WindowHost(document.getElementById("host"));
host.width = host.height = new ui.Unit(100, ui.UnitType.Percent);
host.theme = "standard";
host.windowStateChanged.addEventListener(handleWindowStateChanged);
host.render();

function handleWindowStateChanged(sender, args)
{
     if(sender.windowState == ui.WindowState.Minimized)
     {
          host.closeAll();
     }
}