It’s not so much that adding a single dummy view wrecks us. Our cell layout has a lot going on, with a fair amount of variable spacing and multiple views often being hidden and swapped out. The UIStackView scrolling performance slog I’m seeing is just sum of all that.
Sigh, oh well. I guess that’s just another refactoring branch I’ll have to shelve for now. Dan > On Jul 6, 2016, at 4:45 PM, Roland King <r...@rols.org> wrote: > > >> On 7 Jul 2016, at 04:37, Daniel Stenmark <dstenm...@opentable.com> wrote: >> >> What’s the best way to achieve variable spacing between children of a >> UIStackView? I know that a popular approach is to add an empty dummy view >> to act as padding, but this is being used in a UITableView cell, so >> scrolling performance is critical and the implicit constraints created by >> adding a ‘padding’ view are a death knell for us. >> >> Dan > > > There’s no trick way to do it, you need some extra view one way or another. > > It’s a bit surprising that adding extra, fixed sized children to the stack > really adds that much overhead, that’s a few very simple constraints, all > constant, and shouldn’t really make that much difference. Perhaps the > stackview is being inefficient with the number of constraints it adds when > you add an extra child. You could take a look at the view hierarchy and see > if that’s the case or not. > > You could try going the other way around and making your real elements > children of dummy views so you get to add the simplest top/bottom-padding > constraints possible to those views, that may minimise the number of extra > constraints added and you get to control it somewhat. But if your hierarchy > is such that it’s straining the constraint system performance wise, whatever > way you try to do this is going to have similar performance. _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
