How to open and close files from UIwindow my function doesn't work

Question

Hello guys!
I am trying to create a simple ui-interface.
I made one button so far.
but my function does not work.
if I run the function without dialog box it works perfectly!
when I running the function in the dialog window, picking a file and open, nothing happens why?
please help me with a correct code.
also how do I write  2 functions that also closing a file and  saving a file?
here is my simple code.
var w = new Window ("dialog");
button.onClick = function () {
OpenMyFile();
w.show ();
function OpenMyFile(){
var myFile = File.openDialog();
app.open(myFile)
Thank you in advance.

Answer 1

Well, to answer your first question, you've added an event listener, but you haven't actually added the button itself.
try this:
var w = new Window ("dialog");
b = w.add("button", undefined, "Click me!");
b.onClick = function () {
OpenMyFile();
w.show ();
function OpenMyFile(){
var myFile = File.openDialog();
app.open(myFile)