test.js

var _txtViewLoc = { x: 0, y: 0 };

function textViewLocationChangedHandler(e) {
    _txtViewLoc = e.location;
}

function window_load() {
    TXTextControl.addEventListener("textControlLoaded", function () {
        TXTextControl.addEventListener("textViewLocationChanged", textViewLocationChangedHandler);
    });
}

window.addEventListener("load", window_load);