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Comment by fwlr | Hacker News Reader

CSS has several long-standing problems in a similar vein to this one, most famous being the “center a div” problem. A simple-to-specify end result (“I just want to center this content within its parent”) is desired, a series of arcane CSS magic invocations are devised and become accepted as the standard invocation to solve the problem (usually using translateX/Y -50%), and eventually a series of formal and more general solutions are implemented in the CSS spec that solve the problem in progressively fewer lines of CSS (first “display: flex; align-items: center; justify-content: center;”, now we are down to “place-self: center;”). It’s good to see that the problem of anchoring tooltips is progressing through this process!

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> now we are down to “place-self: center;”

`place-self` still requires the parent to be a flex-box container, though. You can't just apply it to an arbitrary element to make it center in its parent.

`place-self` is just shorthand for setting both `align-self` and `justify-self` in a single proeprty - I don't see how this is necessarily an improvement: CSS is already (unfortunately, necessarily) confusing at it is, so adding a literally redundant CSS property with a distinct name is not going to reduce confusion nor make CSS any more accessible.

CSS's shorthand properties work best when the shorthand version actually aids comprehension, rather than making you think: for example, `border: <width> <style> <color>;` and `margin: <top> <right> <bottom> <left>;` are great examples of how they should be: either because each parameter is unambiguously typed (in `border`'s case: widths, border-style and colors are very distinct) or uniformly-typed but follow a familiar pattern (e.g. `margin:`'s parameters are all length-values but are in a clockwise sequence) - this is not something we see in some of the more modern shorthand properties like `flex` and `box-shadow` where you need to have pre-memorized which parameter corresponds to each longhand property, e.g. it's non-obvious that the `2` in `flex: 1 2 3px` is for `flex-grow` - or that the `3px` in `box-shadow: 1px 2px 3px 4px rgba(0,0,0,0.2);` is for `blur-radius` and not `spread-radius`.

> It’s good to see that the problem of anchoring tooltips is progressing through this process!

I'm also strongly in favour of this CSS feature, it's a long-time coming - BUUUUT I also really would have liked some browser-native tooltip/title feature that allows for rich-content without resorting to hacks like `foo[title]::after { position: absolute; content: attr(title); etc }`

> You can't just apply it to an arbitrary element to make it center in its parent.

You can with grid-first.

With the proviso that third party components may not work (which is fine, third party components are usually very low quality). I'd recommend, right after your existing:

  *,
  *:before,
  *:after {
    box-sizing: border-box;
  }

Adding:

  div {
    display: grid;
  }

You can now remove:

- all margins (there's just padding and gap now)

- margin auto centering hacks

- clearfix hacks

- translateY -50% hacks

- a billion wrappers around every UI element (per all those low quality third party components, particularly common in the react space which seems to have a culture of "add divs until it looks right")

plus a bunch of other code.

In 99% of cases, using grid-first, there will be a 1:1 match of element to UI - getting around the div-soup of older web apps.

The app I'm developing now is 1:1 with the exception of rounded gradient borders, which still needs a hack.

> ...your existing

I don't use CSS Reset techniques: don't try to fight the browser.

> div { display: grid; }

I'm concerned this will have a nontrivial impact on browser layout performance. Existing browser layout engines are heavily optimized for flow/block layout, but defaulting every div to grid breaks that major assumption all the browser-makers made and... for what gain? I actually don't want every div to potentially be a grid layout container by default.

> You can now remove $things:

I don't use any of those tricks/hacks anyway - and clearfix hasn't been relevant since IE8 came out.

> rounded gradient borders

Just use border-radius combined with `border-image: some-gradient-function()`. No hacks or tricks required.

>some-gradient-function()

>which still needs a hack

I've been doing grid-first for a few years now (last major update was when buttons hot grid support) across apps including high performance google docs-type collab interfaces. It's fine.

Optimising for existing behavior reminds me of when people didn't want to use async/await as V8 'wasn't optimised' for it. await never felt slow in their apps anyway, but now it's similar fast to what callbacks were. Skate to where the puck going to be.

> for what gain? I don't use any of those tricks/hacks anyway

OK. Everyone else does but maybe you're the exception.

> For rounded gradient borders... just use border-radius combined with `border-image: some-gradient-function()`. No hacks or tricks required.

Are you sure? https://stackoverflow.com/questions/51496204/border-gradient... - judging by the views on that question, if you have a codepen there's at least 42,000 people who'd love to see, it my understanding is that the W3C spec says it shouldn't work.

Probably obvious, you sound like you know what you're doing but: adding additional elements, pseudoelements etc counts as hacks.

Here's border-radius combined with `border-image: some-gradient-function()`:

https://codepen.io/mikemaccana/pen/QWVpdmo

Thank you for that info - I honestly didn't know that border-radius didn't work with border-image.

It’s OK! Thanks for replying politely. HN can be combative sometimes.

> I'm concerned this will have a nontrivial impact on browser layout performance. Existing browser layout engines are heavily optimized for flow/block layout

Layout and paint performance is pretty low stakes. Unless you’re doing a lot of painting, or your demographic is surprising, your users are going to be fine.

> I'm concerned this will have a nontrivial impact on browser layout performance.

I've experienced this with iOS Safari. I was experimenting with different layout methods, and at one point a display:grid didn't get deleted, and some days later when I was testing with Safari it was taking at least half a second to render a page. I'm talking 5 paragraphs of text, possibly with subgrid I was experimenting with, nothing crazy. I had no idea CSS could ever get that so slow and I thought it had to be something with React, and it took way longer than it should have to narrow it down to that single property.

Parent element "modes" that affect child layout and "enable/disable" child available properties is what makes CSS tricky. To do CSS well you end up having to learn all the modes and all the properties, which makes CSS a defensible professional specialization, but its less good for drive-by designers who just want simplicity. (My personal favorite remains the good old "absolute layout".)

(Aside: another technology in the thankfully small know everything before you can do anything set is gradle, a popular build tool in the Java universe. These tools are capable, but quite demanding of the user. Git may also qualify.)

Right.

Prior to CSS, it used to be that literally anyone could (and should!) write HTML: web-pages were just simple documents (by design) using only paragraph-flow content with inline objects (like images, Java applets, ActiveX on Windows), and appearance was directly set inline with <font>, <small>, etc. This is fine for web-page documents, but not web-page applications, and it turns out that defining a layout system for a medium as flexible as a web-browser viewport is very, very hard.

It's the same thing with desktop software: previously it was perfectly acceptable for a VB6 application to consist entirely of fixed-size windows with controls placed at fixed-positions, with no resize logic - or to handle re-flow when the text changes, or high-DPI for that matters. Users, today, have much higher expectations, and now it's now basically impossible for a "citizen programmer" to meet the expectations of normal users, and I feel this is a bad trend for everyone: we all love to grimmace at a giant Excel VBA macro doing 20 things at once that still somehow works, but the person or company that actually has that macro really is better-off than someone without it.

-------

The complex layout systems in modern UI frameworks (like WPF/XAML, Cocoa Touch, etc) are converging with CSS (or vice-versa, depending on your experience) in their expressiveness - which necessitates complete abstraction-away from fixed-layout WYSIWYG systems that were the key component of the democratization of desktop computers since the late-1980s, and while HTML was never WYSIWYG an average person could still immediately understand what `<font color="">` did - and could immediately see how their fixed-layout VBA Form would look when it runs.

Unfortunately I don't have a solution to this problem: citizen-programmers are going to need a WYSIWYG fixed-layout design tool, but such a tool is fundamentally incompatible with end-user expectations - and essential things like accessibility and device-portability. I guess we'll be stuck with proprietary, half-arsed, "low-code"/"no-code" tools for a long while.

Even longer ago, with fixed width fonts and fixed size screens things were even better. On C64 the keyboard had --- ||| characters to draw line with corner characters T splits and + . The empty space was filled with space characters so you could just move around your cursor. Someone with no previous experience could draw boxes and make cool looking menus. Could stick a few sprites on it with absolute positioning.

Supporting all kinds of screen sizes is a dumb idea but we are stuck with it. If you also want to support different languages the screen is mostly empty with logograms and the languageswithgiantwords stick out of the boxes. We are pretty lucky English is a reasonable middle ground.

> Supporting all kinds of screen sizes is a dumb idea

No, it isn't a dumb idea.

> If you also want to support different languages the screen is mostly empty with logograms and the languageswithgiantwords stick out of the boxes.

...what you're describing only happens if a page/screen/layout is designed without reflow in-mind. Otherwise it will look fine and natural. Every layout system that supports text reflow will support forced hyphenation for dealing with zeverylongcompoundwords in German and other languages.

If you make a painting it is suppose to be viewed at a specific size. If you specifically create it to work at different sizes (like a logo) you suffer enormous constraints. I took a picture one time of a boat on the horizon under a beautiful sky with a few distant seagulls that, while small, were absolutely necessary for the composition. It looked stunning full screen, one could almost smell the ocean. When slightly scaled down the clouds turned uninteresting, the boat lost all detail, the waves and the gulls just vanished.

One could certainly argue that there is no need for such things and that an interface can be (or should be?) equally usable on any kind of screen. To me it stops being art at that point. It reminds me of The Night watch, they "reflow" the painting by cutting parts of. People thought one can just do that. Or perhaps they showed it's not a problem, I dunno. It's not for me.

I completely agree with your take on what makes for a good shorthand property, I would also have pointed to border: as a good shorthand and flex: as a bad shorthand. I think place-self: is a good shorthand, though - the fact that it’s a redundant way to specify two separate properties in a single line is good in this specific case because it matches the developer’s mental model of “center this div please” being a single and simple request. Yes, the truth of layout is that centering stuff is not actually simple and does not involve one single operation, and so we have had to build complex layout systems to handle all the edge cases and complexities, but now that we’ve built those systems it makes sense to offer a shorthand for this common request that resolves to the set of commands required to achieve the result. (e.g. I think ES6’s for-of iteration construct is a good idea, despite redundancy/confusion with the existing C-style for-i++ iteration construct.)

Fully agree with your take. CSS should have more straightforward properties that actually do what people intuitively expect it to do without additional dependencies and weird side effects.

Even the supposedly favorable case of having a flexbox container with place-self: center in many cases still does not correctly center the child element. For example, a label inside a button. The label is typography, which means it has its own vertical spacing (line-height, top-cap, bottom margin) that may be unevenly distributed. Fixable, but now you're into the 3rd rabbit hole, just to center something.

Every few years I have to look up what the current state of the art is for centering something in CSS. I've so often been shocked that there still wasn't something as simple as <center>. Similarly, I couldn't believe how long it's taken to get something as useful as tables for layout.

I also used to be annoyed by how long it took to get “basic useful functionality” for some use case in CSS. Over the years I have mellowed as I recognized it simply takes a long time to converge on what functionality is actually desired, and then what systems need to be in place so you can request that functionality in the most obvious location in your code (e.g. it turns out we really want to put the request for centering on the element to be centered, not the parent) along with figuring out the truly minimal, truly necessary information to carry out that functionality — and then further still to implement those needed systems in all major browsers. It’s just a long and incremental process by its nature and we probably can’t do much better than that. Ironically, the fact that the state of the art changes every few years is evidence that this process, though slow, does work reliably well.

<center> is effectively

    <div style=”text-align: center;”>
      <span>centered element</span>
    </div>

Not so easy, at least:

    <span style="display:inline-block">centered element</span>

But in general <center> still cannot be 100% expressed by CSS means.

<center> just centered text horizontally. This have been supported by CSS from the beginning.

The CSS property display:table gives you the same layout power as tables.

Never heard of place-self before! I've always resorted to fumbling around with flexbox froggy and wondering why the changes I make to froggy seemingly don't do the same thing to my simple HTML.

First I've heard of place-self as well. I see it's been available for quite some time. I've always used the "longhand" version instead of this shorthand property. Good to know.

Laughing in bed because I always assumed I was the only one using froggy as my flexbox reference material.

The worst is when you get angry and start blaming the frog for its lies. As if it's the frog's fault...

If we would have flex units instead of display:flexbox then this:

   div {
     width:max-content; 
     margin:*;
   }

is enough to place block in the middle of its container (vertically and horizontally), see: https://terrainformatica.com/2018/12/11/10-years-of-flexboxi...

Mt secret is to use <center> but I cant remember how many times I've considered using js and absolute positioning. The user clicks an image, the image is enlarged to fit the viewport, remaining space is filled with a color. Doable with css. The user zooms the image (scale), so far so good... the user pans the image... uhh how do I limit panning in css? bounding rectangle + get computered style??

Pan by adding a wrapping element with ‘overflow: hidden’ and use ‘translate’ to move the child image element inside it.

That sure saved me a lot of time making something ugly that shouldn't exist.

Thanks!

With display:flex on the parent you can just put margin:auto on the child. That's what I do and it works fine. Although I admit to having used the transform trick more than a few times before flexbox was a thing.

> most famous being the “center a div” problem

It's crazy how many attempts at this have been done over the years. And it worked great in Adobe Flex, back in 2009.

Whaaaaaat? I thought

> margin: 0 auto;

would be the way to go for centering divs...

https://jsfiddle.net/c7gt4or2/2/

No luck for elements of unspecified widths, or for inline elements.

Ah yes, but that's what container-divs are for, am I right?! ;-)

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