Click empty admin bar to scroll to top

[TJNowell]

I've attached a patch that will duplicate behaviour from the Google+ black bar at the top of the page in the admin bar.

Apply patch, scroll to the bottom of a long page, and click a vacant area of the admin bar. The page will scroll to the top when clicked.

Tested on IE7/8/9/Chrome/Firefox/Safari, includes JQuery version and fall-back javascript version

For those still unsure what this patch does:

​http://www.howtonew.com/google-trick-click-the-upper-black-bar-to-go-to-the-top

Interesting idea.

Minor note: Please make patches relative to the root WP directory.

Patch remade relative to wordpress root folder

I also think the idea is interesting.

Even if the idea was not in use with G+ it still has great UX potential.

It also matches the touch status bar to scroll to top behaviour in iOS

Duplicate #19534

Adding a patch that had been applied to an (apparently) duplicate ticket.

My patch (tagged 19534.diff) adds a jQuery scroll-to-top function if jQuery is enabled, or a smooth scroll that works in every browser (tested in Firefox, IE 7/8/9, Chrome at least) if jQuery is not being used.

The patch has been tested by a handful of people already and is verified to work with WP 3.3.

I was sorry to see this didn't make it into 3.3.

+1

New patch cleans up some code and makes a few conditional statements easier to follow.

I realized that a couple of my conditional statements were tricky to follow: if (leapY < stopY) leapY = stopY; timer++; actually caused me a couple of issues just reading back my code ... so they're now broken up and fixed a bit.

I've also removed the arbitrary stopY variable. Since we're always scrolling to the top, there's no reason to set that separately.

New patch tested against trunk. Only adding the unminified version in case we need to make further changes.

Working well so far for me with latest Chrome and Firefox on Mac OS.

+1

And, since I happen to have some VMs up: Eric's latest version works well in IE8 and IE9

I like the concept and it works. That said, the code could be a bit cleaner (both stylistically and logically). I'll post up a revised patch.

Revised patch posted. Haven't tested IE yet.

Works fine on IE8 and 9. Doesn't seem to work on IE7 (clicking the admin bar doesn't scroll to the top) but nothing breaks, either (no errors are thrown).

Scratch that. The jQuery version works in IE8 and IE9 (not IE7).

The non-jQuery version works in IE9 but not in IE8 or IE7.

With IE7, the problem seems to be with e.srcElement. In both IE7 and 8, e.target is undefined, so e.srcElement is passed to the function instead. Unfortunately, it's passing the wrong target ID to IE7 ("wp-admin-bar-top-secondary") so it fails the initial conditional check.

In IE8, it seems that startY is evaluating to 0 no matter what the scroll position seems to be.

Patch fully compatible with IE7-9

Did some work on the patch and fixed it to work with IE7-9. If we're not supporting IE7 (I missed the dev chat, so I'm not sure if we're still supporting that browser or not) then we can lose the && t.id != 'wp-admin-bar-top-secondary' part of the id selector conditionals. The patch will function just fine in IE8-9 without that, but it's needed for IE7 because of the way the right-hand side of the toolbar is presented on the page.

Also, the fix for IE8 is to use document.documentElement.scrollTop to get a value for startY. I've added that fix as well.

Fully tested in every browser I have access to (IE7-9, Chrome latest, FF latest, Safari) on Windows 7. Works both with and without jQuery.

Replying to ericmann:

Yes, there are other browser differences too. Perhaps best would be to load jQuery on the front end when the toolbar is shown. Can namespace it completely with wpjq = jQuery.noConflict(true); or similar so it doesn't conflict with another jQuery version.

Replying to azaozz:

Yes, there are other browser differences too. Perhaps best would be to load jQuery on the front end when the toolbar is shown. Can namespace it completely with wpjq = jQuery.noConflict(true); or similar so it doesn't conflict with another jQuery version.

I think loading jQuery on the front end, just to scroll the page when you click on the admin bar, is a bit overkill. If it's already loaded by the theme, we use it. If not, we should have a reliable, browser-agnostic fallback. The new patch I've posted should handle that.

Not just to scroll, would make the drop-downs consistent by using hoverIntent too. Were planning to try that in 3.3 but ran out of time at the end.

I am still on the fence as to whether loading jQuery on the frontend is more trouble than it is worth. Namespacing should help, but there's a lot of opportunity for conflict here.

I'm in support of loading jQuery on the frontend, but the risk from loading a duplicate copy bothers me. On top of conflicts it's a small extra server load + bandwidth, and would be even worse for mobile sites/themes. If we do include any scripts then better de-duplication in wp_enqueue would be my pick (not straightforward though) over namespacing.

+1 for Eric's patch though. The browser-to-browser differences are very minor, and if/when jQuery becomes universal those will disappear.

Tested the patch. Looks good. It's a bit slower in non-jQuery mode.

18758-4.patch is about the same as 18758.3.diff but adjusted the speed in non-jQuery mode. Also removed some redundant logic ([document/window/body].scrollTop cannot be < 0).

In [19846]:

Click empty toolbar to scroll to top, props ericmann, fixes #18758