Ed's Odd scrolling issue

Discussion in 'HTML' started by Neil Gould, Feb 4, 2014.

  1. Neil Gould

    jfaerber172 Guest

    I still don't understand the FF issue with Ed's page and your discussion.
    just wanted to add this http://solutions.trendsmap.com/
    that page uses a different speed for a background image in the middle
    but yes, I heard recently complains about FF on linux ubuntu -
    the scripts didn't work as expected after an update
     
    jfaerber172, Feb 16, 2014
    #61
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  2. Neil Gould

    dorayme Guest

    Roughly this, it started with that the latest FF browsers only partly
    knew that there was a fixed header (and perhaps footer but let's keep
    it simple). It knew in that it displayed the HTML/CSS as the author
    intended, it also knew in that when a user used the Page Down command
    (e.g. on a keyboard), the content at the bottom of the content would
    scroll to the top of the content.

    It did not know in that when a user gets a mouse pointer on the
    scrollbars and clicks under the bottom handler (an alternative Page
    Down action in FF as with some other browsers) it made the bottom of
    the content disappear under the header.

    FF does have algorithms for getting Page Down as is wanted in some
    circumstances. The browser can detect that the header is fixed *and*
    completely across the viewport (as when e.g. width is specified to be
    100% when there are no side borders or paddings in the direct BODY
    containing element) and probably is of a modest height.

    But, to the consternation of the OP, it does not apply this or a
    functionally equivalent algorithm to the Click Under Scrollbar
    handlers.

    The wider issue was that many browsers people use don't even do Page
    Down as is wanted with fixed headers. Other issues were to do with
    there being no respected standards on all this, that it was
    complicated in that there are other sorts of fixed header designs
    where content from the bottom is wanted to scroll to the top of the
    viewport.
     
    dorayme, Feb 16, 2014
    #62
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  3. Neil Gould

    Gus Richter Guest

    In a past posting here, I suggested to use the approach I would take (of
    which I gave a demo):

    +--------------+
    | fixed header |
    +--------------+
    +--------------+
    | |
    | scrollable |
    | |
    | section |
    +--------------+

    I believe the OP indicated that it resolved his problem.

    Instead of the OP's method of placing a fixed item within a scrollable
    section:

    +---------------+
    |+-------------+|
    || fixed header||
    |+-------------+|
    | |
    | scrollable |
    | |
    | section |
    +---------------+

    I can understand why a browser would have trouble with this, or why
    anyone would wish to use this method.
     
    Gus Richter, Feb 17, 2014
    #63
  4. Neil Gould

    Gus Richter Guest

    I'm not saying that you're doing something wrong. I'm suggesting to use
    a different approach, that of not embedding the fixed div within the
    scrollable div, but to have two distinctly separate divs. It's the way I
    would do it (see the demo I provided in another thread). The fixed one
    within a scrollable one seems to me to be contradictory and could cause
    problems (apparently it does?), although the fixed one is removed out of
    flow - as in absolutely positioned.
     
    Gus Richter, Feb 17, 2014
    #64
  5. Neil Gould

    dorayme Guest

    ....

    Your example, when generalised, seems to suffer the same glitch in FF
    that was pointed out in the first place. Even Page Down does not work
    as you would want in other browsers.

    Is there something significant and crucially relevant in your proposal
    different to

    <http://dorayme.netweaver.com.au/fixedHeaders/fixedHeader_gr.html>

    which fails to address Ed's concern.
     
    dorayme, Feb 17, 2014
    #65
  6. Neil Gould

    Gus Richter Guest

    Just to get our reference right, we're talking about:
    If you mean immediately after your:
    <!-- END menu HTML import-->
    </div>

    up to just before:
    </body>

    and then applying/moving the styles required for this div as applicable
    from body { ..... } ?
    This would fit the first ascii drawing as I suggest.

    I believe so.
    I remind you of my demo:
    <http://codepen.io/anon/pen/FwAdr>
    and since I was unsure as to your problem, I asked, "Does it relate and
    help?" to which you replied, "Definitely relates. I can see that what
    you've done results in the phenomenon going away. I must confess I
    don't understand why!"
     
    Gus Richter, Feb 18, 2014
    #66
  7. Neil Gould

    Gus Richter Guest

    OK, so I recall that I originally did not contribute to the thread re.
    his "problem". The reason was that I did not think it a coding problem
    but something nitpicking on the client side and it did not interest me
    and to be honest, I did not understand the "problem" since I could not
    see it.

    Later due to the numerous posts, I thought it was related to another
    problem I was involved with and questioned if it related - a demo
    included. Ed stated that it worked.

    Based on his response, I tried much later (now) to explain, since the
    perception on my part was that there was a misunderstanding as to what I
    was saying.

    Now you say (with understanding of what I've been saying) that it does
    not work, so I've carefully read Ed's problem:
    "If I click in the vertical scroll bar below the handle the page
    scrolls down more than one full screen."
    I've now checked his original page and your demo on several browsers and
    find the following:
    1. I've misunderstood the "problem".
    2. All other browsers (webkit & IE) except for FF scroll down, every
    time, exactly one screen no matter where I click past the vertical
    scroll handle.
    3. FF scrolls down proportionally. So, just past the handle, one
    screen. Half way down, FF scrolls half way down the page, three quarters
    down it scrolls down three quarters down the page/doc., etc.

    The bottom line, as I see it, is that it is a matter of browser design.
    I kind of like that I don't have to click several times to get to a
    point beyond several screen full, although I don't use this "feature"
    very much. A FF user should be aware of this feature and recognize that
    it is not a failing, but an added "feature". It could be said that all
    other browsers should have this "feature".

    My initial thought on this thread is hereby confirmed to me and I'm
    sorry that I joined in, although I remain firm on my layout suggestion
    even though the questionable (to me) one works. Beyond this, I'm out of
    this thread. Sorry for the confusion I caused.
     
    Gus Richter, Feb 18, 2014
    #67
  8. Neil Gould

    dorayme Guest

    You have not caused any undue confusion. This is a usenet thread and
    it is important for one's sanity not to have very high expectations.

    * The main problem that OP saw was that Page Down worked as he
    expected with his pages but Click Under Scrollbar handler did not in
    FF.

    * Some fixed header designs can seem to operate well in very limited
    conditions (the particular viewport size of a user, the text size, the
    height of the header etc). But flex these as is the case in the real
    world and things often do not work so well.

    * It is a browser problem insofar as OP's concern (his intense and
    unshakeable focus was Mozilla and the difference between Page Down and
    Click Under Scrollbar handler (this is to all intents and purposes the
    same functional command, just differently delivered (keyboard vs
    mouse).

    * The problem is wider than this and affects other browsers, it is not
    just a Mozilla thing, notwithstanding your experience with a site you
    helped someone on (not even Page Down works on the URL I gave of the
    essentials of your url in my Safari, to take just one webkit browser).

    * FF is a bit of a tease in all this in that it sets up expectations
    that are easily dashed. It tries and often can succeed in making Page
    Down (the keyboard command) work in fixed header situations where
    other browsers quite fail.
     
    dorayme, Feb 18, 2014
    #68
  9. Neil Gould

    BootNic Guest

    [snip]
    about:config ui.scrollToClick default is 0

    by default firefox will page up/down when the page up/down part of
    the scrollbar is clicked.

    [​IMG]

    Some browsers will scroll to click with SHIFT + CLICK on the page
    up/down parts of the srollbar


    --
    BootNic Tue Feb 18, 2014 09:17 am
    Behind every successful woman...is a substantial amount of coffee.
    *Stephanie Piro*

    -----BEGIN PGP SIGNATURE-----
    Version: GnuPG v1.4.11 (GNU/Linux)

    iEYEARECAAYFAlMDa4kACgkQOcdbyBqMFBEESwCgh5iwKt97LuqVDW2k61HC+YhW
    Tn4AoOAa/RgYvioylg4fG4eVSM8JWHDW
    =Rexf
    -----END PGP SIGNATURE-----
     
    BootNic, Feb 18, 2014
    #69
  10. Neil Gould

    dorayme Guest

    Not even Page Down works as you would want on my Chrome (send a bug
    report to Chrome), and it does not work under my Windows in Virtual
    Box either - not under different user text settings and viewport
    settings that you might not be expecting. Will you send a bug report
    to them ("Dear Chrome, not everyone in the world ...")?
    I should take your word on this, but my experience so far on this
    business makes me doubtful. No offence intended. I will try to take a
    look on my Virtual Box (but I am on XP Pro there).
    I will test this when I get my hands on a capable machine for it.
    Do me a favour Ed, take out an ad in The New York Times so you get all
    the browsers at once. That should get you some letters back from the
    browser makers explaining how it is not exactly as easy as slicing
    butter with a hot knife.
     
    dorayme, Feb 18, 2014
    #70
  11. Neil Gould

    dorayme Guest

    It is not me who is worried about this business, I am happy to use the
    mouse wheel scroll or Page Down (where it works) and I am less likely
    to use fixed headers and if I did, less likely to worry about how
    people scroll. So you better get cracking: write to Chrome, Safari,
    I guess it is wrong to assume that you are interested in your visitors
    using any browser other than FF (many of which fail in Page Down,
    never mind Click Under) in all sorts of OS environments
    Native, schmative, it is what some people use to browse some things.
    The fact is that visitors to web pages use all manner of ways to
    access your pages and if you are worried about a failure in FF over a
    matter, it seems surprising you are so dismissive of failure on the
    same score in other browsers and OS's and environments.

    btw, I have since looked at Safari on Windows since and it fails to do
    what you want in respect to fixed headers and scrolling.
     
    dorayme, Feb 19, 2014
    #71
  12. Neil Gould

    dorayme Guest

    I will say it again, your type of fixed header design (as many others)
    also fails in FF with respect to Page Down (to take FF's strongest
    card) under some user text size, zooming choices, viewport
    configurations. This routine is no magic god.

    Don't be hard on yourself, why should you be expected to *figure out*
    something that browsers don't or can't do?

    ....
     
    dorayme, Feb 19, 2014
    #72
  13. Neil Gould

    dorayme Guest

    It is unclear what you are doing exactly and with what URL? I made an
    Ed type test case, gave the url to it and it does not work at large
    text sizes in narrow but not silly narrow viewports on Zoom Text Only
    on my FF 27.01. I am looking at it not working as you would want right
    this minute. And that is just FF. There are other browsers too where
    it does not quite do what you want.

    So you say? Which ones? Maybe if you limit the height of the fixed to
    a fixed small px count, if you give a min-width to it, you will get
    the result you want in some browsers whose algorithms can handle very
    restricted conditions.
    You have been curious about a very focussed matter to do with very
    narrow conditions. In the hands of the general public this sort of
    concentration can be blown wide open. What am I saying? I am saying
    there are wider issues to do with *robust* design that puts a page
    safer out of reach of the evil forces in the real world that would do
    bird like things on it from a great height.
     
    dorayme, Feb 19, 2014
    #73
  14. Neil Gould

    Ray_Net Guest

    Every, yes i say "EVERY", bug i reported against SM .... never end with a correction.
     
    Ray_Net, Feb 20, 2014
    #74
  15. Neil Gould

    dorayme Guest

    And what would it be in browsers where neither Page Down nor Click
    Under work as you would want? A general failure, an inadequacy? What
    if FF just did something special for Page Down but never got around to
    doing something you want for Click Under? Would the bit that they
    failed to do be less of a bug and more of what other browsers fail to
    do, a lack of a possible action.

    It might be a bug if somehow it *always* worked in the past with both
    Page Down and Click Under, then in some upgrade something rather
    obscure went wrong with the code that was intended to work with the
    Click Under.

    All this without going into the assumption that even Moz Page Down
    always worked well with fixed headers.

    I feel like some sort of cynical gala perched on a branch snapping at
    people passing under. Please forgive me. <g>
     
    dorayme, Feb 20, 2014
    #75
  16. Neil Gould

    dorayme Guest

    It might be reasonable to expect that Click Down works as Page Down
    works. But is this relevant to the question of whether it is a bug if
    it does not?

    It is not unreasonable and maybe you are right. We are focussed here
    on you thinking a bug is at issue. It is hardly a bug issue with other
    browsers that fail to do what is wanted with certain fixed header
    designs. They just don't cater for such a complexity. Maybe the FF
    people have not got around to addressing the Click Under effect in
    fixed header situations. That does not *make it* a bug.
    Why is this nonsense? I reread my words and they make eminent sense -
    perhaps I am biased! <g>. If a piece of software has two commands (one
    from a keyboard, the other from a mouse) that result in exactly the
    same effect for years and years and suddenly a new version has
    different effects for these two same commands, then something has
    changed. There needs to be an argument that it is *a bug*. Maybe it
    is, maybe not.

    If a piece of software *now* - forget about the past - does something
    you want in one command but not in another command where it is
    reasonable to expect the same in effect, there needs to be an argument
    that it is a bug. A bug is more than that someone has not bothered to
    do something. It might be the result of this, but it is not identical
    to it.

    Fine. How it is now is that it is not even totally reliable in Page
    Down in the way we might expect where an author designs with fixed
    headers but in a way that allows great flexibility in user viewport
    width and text size.
     
    dorayme, Feb 20, 2014
    #76
  17. Neil Gould

    Ray_Net Guest

    It's not because it's pretty damned simple that the developers will do it. They
    prefer play with new gadgets instead of correcting their bugS.
     
    Ray_Net, Feb 20, 2014
    #77
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