Reloading table view with negative top content inset causes strange behavior

Originator:skagedal
Number:rdar://37824199 Date Originated:23-Feb-2018 02:47 PM
Status:Open Resolved:
Product:iOS + SDK Product Version:11.2
Classification:Serious Bug Reproducible:Always
 
Summary:
When a table view has a negative top content inset and uses fixed row heights and you do a reloadData, the scroll view gets in a weird state where it rubberbands to an incorrect position. If you pull it “long enough”, it resets to the correct state.

Steps to Reproduce:
- Download included sample project, also available at https://github.com/skagedal/radars
- Run in an iOS 11.2 simulator or on device with Xcode 9.2
- Press “Toggle Preview”
- Press “Cause Problem”

Expected Results:
- Nothing visible happens, table view reloads.

Actual Results:
- Content disappears up above the visible area. If you drag it down, strange stuff happens with cell separators.

Version:
11.2

Notes:
A workaround is to implement estimatedRowHeight and return the same values as rowHeight. This fix is included in the code repo as commented-out code.

Comments

See https://github.com/skagedal/radars for example.

By skagedal at Feb. 23, 2018, 1:55 p.m. (reply...)

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