Question

I’ve got a web page with a button that opens another window.

When the button is clicked and the new page is open, I disable the button (because a need only one page is opened clicking the button).
I use window.open() and not windows.showModalDialog() because the user should work on both pages.

When the second page is closed I have to re-enable the button in the first page.

I’ tried with something like this:

var win = window.open("SecondPage.htm");
// disable button        
while (!win.closed) {
    setTimeout('', 2000);
}
// re-enable button

But using the while loop slows too much the browser, so it’s actually impossible to work on the first page…

Is there a better solution to my problem?

Answer 1

setTimeout('', 2000)

is NOT sleep()

Your while loop keeps turning, and will indeed consume all the CPU, thus slowing down the browser.

Better:

var win = window.open("SecondPage.htm");
// disable button        
setTimeout('enableButtonIfWindowClosed', 2000);

function enableButtonIfWindowClosed {
  if (windowClosed()) {
    enableButton();
  }
  else {
    setTimeout('enableButtonIfWindowClosed', 2000);
    //function recalls the function itself
  }
}