Re: [csswg-drafts] [css-sizing][css-grid][css-flexbox] Intrinsic Sizes, Scroll Containers, and Grid/Flex Sizing

The Working Group just discussed `intrinsic size of 'overflow: auto/scroll' and its impact on auto-sized grid/flex item ancestors`.

<details><summary>The full IRC log of that discussion</summary>
&lt;gregwhitworth> Topic: intrinsic size of 'overflow: auto/scroll' and its impact on auto-sized grid/flex item ancestors<br>
&lt;astearns> github: https://github.com/w3c/csswg-drafts/issues/1865<br>
&lt;gregwhitworth> fantasai: grid and flexbox show this issue, where people have an element with a scrollbar and they put it among a whole bunch of other content<br>
&lt;gregwhitworth> fantasai: it forces that has a min-content size which defeats the purpose of the scrolling the author defined<br>
&lt;gregwhitworth> fantasai: this leads to a lot of confusion for authors<br>
&lt;gregwhitworth> fantasai: they're already handling their overflow and it would be nice if they just worked<br>
&lt;gregwhitworth> fantasai: this was filed that would allow us to come up with a way for this to work<br>
&lt;dbaron> q+<br>
&lt;gregwhitworth> fantasai: I was talking with cbiesinger on Saturday to try and have the min-content zero'd out<br>
&lt;gregwhitworth> fantasai: the min-content contribution which has overflow be 0, but not the logical height depending on its overflow. If you did this you'd have to relayout in flow content to determine it's min and max<br>
&lt;fremy> q+<br>
&lt;gregwhitworth> fantasai: it's an idea, we're looking for other ideas<br>
&lt;dbaron> q-<br>
&lt;gregwhitworth> dbaron: The thing with overflow that is not visible the size is the content within it, it has to propagate through it if it's the only thing<br>
&lt;gregwhitworth> dbaron: I tend to think, that there is not going to be a thing that we can do to solve this with a property that allows them to choose the thing that they want<br>
&lt;gregwhitworth> dbaron: I think there are two different scopes<br>
&lt;cbiesinger> q+<br>
&lt;Rossen> q?<br>
&lt;gregwhitworth> 1. intrinsic control intrinsic width that has overflow<br>
&lt;gregwhitworth> 2. properties that allow assignment to the intrinsic widths<br>
&lt;gregwhitworth> dbaron: the advantage of the first one is it gives more room for auto behaviors that do the right thing<br>
&lt;gregwhitworth> dbaron: the advantage of the second is it is strictly more powerful<br>
&lt;fantasai> q+<br>
&lt;Rossen> q?<br>
&lt;Rossen> ack fremy<br>
&lt;gregwhitworth> fremy: I wanted to note that we had a similar issue in the table spec<br>
&lt;gregwhitworth> fremy: if you have a % height and you're overflowing in a non visible way we should resolve to 0<br>
&lt;gregwhitworth> fremy: the author intent is pretty clear here<br>
&lt;gregwhitworth> fremy: to me this makes sense and is generalized<br>
&lt;Rossen> q?<br>
&lt;gregwhitworth> fantasai: for grid and flex items specifically the automatic minimum size is not triggered on items that are not with overflow that is not visible but it does impact content contribution<br>
&lt;gregwhitworth> cbiesinger: you said that the single items need the content contribution to propagate through<br>
&lt;gregwhitworth> dbaron: because people will use it to hide things rather than scroll it<br>
&lt;gregwhitworth> fantasai: that's a good point<br>
&lt;fantasai> s/use it/use 'overflow: hidden'/<br>
&lt;gregwhitworth> dbaron: you're talking about zering out the min-content sizes<br>
&lt;gregwhitworth> fantasai: yeah, just the min-content size<br>
&lt;smfr> s/zering/zeroing/<br>
&lt;Rossen> q?<br>
&lt;Rossen> ack cbiesinger<br>
&lt;gregwhitworth> dbaron: presumably the min-content sizes don't matter<br>
&lt;gregwhitworth> cbiesinger: for the min size of flex and grid would make it zero in this cases<br>
&lt;gregwhitworth> dbaron: in many cases you want them to get smaller but not to 0<br>
&lt;gregwhitworth> fantasai: a lot of the cases that are here the minimum would be controlled by other content that happens to be there<br>
&lt;gregwhitworth> fantasai: if they don't want it to get to 0 they can set a min size on the flex or grid item<br>
&lt;fantasai> or on the scroller itself<br>
&lt;gregwhitworth> dbaron: the other thing I worry about here is compat<br>
&lt;gregwhitworth> cbiesinger: that is concerning<br>
&lt;gregwhitworth> dholbert: Chrome already does this correct?<br>
&lt;fantasai> This is more understandable than having a scrollable descendant of a grid or flex item several layers deep in a subsection of a subsection cause the flex/grid item's width to explode out<br>
&lt;gregwhitworth> cbiesinger: I don't think we do that, but we do is for column flex we don't give it a min-height<br>
&lt;gregwhitworth> dholbert: I thought there was something there for overflow: scroll<br>
&lt;gregwhitworth> cbiesinger: I'd need to look at it<br>
&lt;cbiesinger> s/column flex/nested column flexboxes/<br>
&lt;fantasai> Proposal in two parts:<br>
&lt;fantasai> 1 flex/grid items with overflow != visible | hidden have min-content contribution of zero<br>
&lt;gregwhitworth> Rossen: I read through the post about this issue, but I'd want more use cases for this. I am not going to object, but there will be compat issues for this<br>
&lt;gregwhitworth> Rossen: dbaron any objections?<br>
&lt;jensimmons> Rossen: can you speak up? You are very quiet. Or move a mike closer to you.<br>
&lt;fantasai> 2 inline dimension of block with ovefow != visible | hidden has mincontent contribution of zero<br>
&lt;gregwhitworth> dbaron: I wouldn't object, but I'd like to discuss the compat implications<br>
&lt;gregwhitworth> Rossen: we can discuss this on the side - let's not rush the resolution<br>
&lt;gregwhitworth> dbaron: I would be hesitant to come up with something too magical<br>
&lt;gregwhitworth> Rossen: unless there is something else to be discussed<br>
</details>


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Received on Monday, 6 November 2017 18:09:41 UTC