Dialog: Don't change z-index when already at the top

it seems "modal" dialog does not move in front of datepicker.

jQuery UI 1.8.1 Uncompressed Version.

jquery.ui.dialog.js

line 80(dialog _create)

.mousedown(function(event) {
	self.moveToTop(false, event);
}),

Test code:(for tests/visual/compound/datepicker_dialog.html)

$('#datepicker').mousedown(function () { return false; });

seems to prevent dialog moving in front of datepicker.

(press tab key to focus #datepicker.)

I don't know how to find the dialog is already at the top.

Test code:(jquery.ui.dialog.js, line 254, dialog moveToTop)

if (self.uiDialog.css('z-index') != $.ui.dialog.maxZ) { //<-append
	if (self.overlay) {
		$.ui.dialog.maxZ += 1;
		self.overlay.$el.css('z-index', $.ui.dialog.overlay.maxZ = $.ui.dialog.maxZ);
	}

	//Save and then restore scroll since Opera 9.5+ resets when parent z-Index is changed.
	//  http://ui.jquery.com/bugs/ticket/3193
	saveScroll = { scrollTop: self.element.attr('scrollTop'), scrollLeft: self.element.attr('scrollLeft') };
	$.ui.dialog.maxZ += 1;
	self.uiDialog.css('z-index', $.ui.dialog.maxZ);
	self.element.attr(saveScroll);
} //<-append

may work.

#7884 is a duplicate of this ticket.

Dialog: Awesome new stacking and overlay implementation. Fixes the following tickets:

Fixes #3534 - Dialog: Modal dialog disables all input elements on page.

Fixes #4671 - Dialog: Modal Dialog disables vertical scroll bar in Chrome & Safari.

Fixes #4995 - Dialog: Modal Dialog's overlay dissapears in IE when content is tall.

Fixes #5388 - Dialog: Don't change z-index when already at the top.

Fixes #5466 - Dialog: "modal" Dialog Incorrectly Cancels Input Events.

Fixes #5762 - Dialog: Get rid of z-index workaround, document it instead.

Fixes #6267 - Dialog: checkboxes that inherit a z-index < jqueryui.dialog z-index don't work.

Fixes #7051 - Dialog: modal prevents tab key from moving focus off slider handle.

Fixes #7107 - Dialog: Modal dialog event loss with high zindex child elements (FF 3.6).

Fixes #7120 - Dialog: Modal operation interrupts drag drop marker functionality on gmaps.

Fixes #8172 - Dialog: Change event cancelled when opening modal dialog from another modal dialog.

Fixes #8583 - Dialog: Mouse event wrongly stopped.

Fixes #8722 - Dialog: Remove stack option.

Fixes #8729 - Dialog: Remove zIndex option.

Changeset: 3829a37ca122e923c3a08b964c4b1a946a2a1456