Subview layout margins do not apply during table cell height calculation

Originator:ilya.konstantinov
Number:rdar://28600418 Date Originated:October 3, 2016
Status: Resolved:
Product:iOS Product Version:10
Classification: Reproducible:Yes
 
Area:
UIKit

Summary:
Subview layout margins do not apply during table cell height calculation.

Steps to Reproduce:
1. Create a UITableView with autolayout heights (UITableViewAutomaticDimension).
2. Add a subview to the content view and set its layout margin to explicit non-default (e.g. bottom=250 instead of 8).
3. Add a sub-subview with some height (either intrinsic or constraint-based).
4. Create a chain of top-to-bottom constraints (to margins) so that table cell height can be calculated.

See attached example with two cells — one sized incorrectly, one sized correctly.
Setting subview's preservesSuperviewLayoutMargins = true works around the issue for some reason I cannot understand.

Expected Results:
Table cell height takes inner subview margins into consideration.

Actual Results:
(8,8,8,8) margins are used during table cell height calculation.

Version:
iOS 10.0

Notes:


Configuration:
iOS Simulator

Attachments:
'TableViewAutoHeightWithMargins.zip' was successfully uploaded.

Comments


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