Open Radar

 
Summary:
In longer table views that use estimated row heights, selecting a row to push a new view controller onto a containing navigation controller can recalculate the table view's contentSize, causing a scroll position shift. In some situations, this can scroll the selected cell entirely offscreen, breaking the user's chain of navigation.

From debugging, it appears that the table view leaves and re-enters the window when the default navigation transition begins. UITableView's -didMoveToWindow then recomputes its contentSize based on the estimated row height; if this height times the number of rows is significantly different from the actual total height of the rows in question, the scroll position jumps by the difference.

Steps to Reproduce:
1. Launch the attached sample app on an iPhone in portrait.
2. Scroll all the way down.
3. Select the last row.
4. Navigate back.

Expected Results:
The last row is still entirely visible.

Actual Results:
The last row has been scrolled partially (or entirely) offscreen.

Note:
Sample app for this radar available at https://github.com/lithium3141/TableViewNavigationContentJump