//gets LSO object / creates if it doesn't exist
var mySharedObject:SharedObject = SharedObject.getLocal("app3");

//output string from LSO to a text field
viewer.text = mySharedObject.data.viewer;

//when button clicked, get textfields current text and save it in LSO
lso_save.addEventListener(MouseEvent.CLICK, saveLso);

function saveLso(e:Event):void
{
    mySharedObject.data.viewer = viewer.text;
    mySharedObject.flush();
}