jQuery UI dialog box not positioned center screen

Question

I have a jQuery dialog box that is meant to position in the middle of the screen. However, it seems slightly off-center vertically.

Here is the code:

Answer 1

If your viewport gets scrolled after the dialog displays, it will no longer be centered. It's possible to unintentionally cause the viewport to scroll by adding/removing content from the page. You can recenter the dialog window during scroll/resize events by calling:

$('my-selector').dialog('option', 'position', 'center');