Bug 23996 - Implementing a TableView with Variable Height Rows
Summary: Implementing a TableView with Variable Height Rows
Alias: None
Product: iOS
Classification: Xamarin
Component: General ()
Version: XI 8.2.0
Hardware: PC Mac OS
: Lowest minor
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2014-10-22 15:53 UTC by Dominic N [MSFT]
Modified: 2014-11-12 01:11 UTC (History)
3 users (show)

Is this bug a regression?: ---
Last known good build:

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Comment 1 Sebastien Pouliot 2014-10-22 16:30:59 UTC
note: Please provide full test case(s) if you want advice on something (even more for advice than a bug). We won't recreate applications around code snippets and it's very likely that the issue exists in some missing code.

A quick _guess_ is that the memory is required only temporarily. That's often caused because GetHeightForRow, when overriden, is called for every (not just the visible) cells in the UITableView. Since that's done (by iOS) in a loop it might take some time for the GC to reclaim any memory allocated during the calls (hence the visible memory spike).

Things that often help are:

* Caching some (or even all) height values (.e.g on first use);

* Precompute (and cache) the height for all cells / items, so the call to GetHeightForRow becomes a single "GetItem().Height";

* Ensuring the height computation can be done without (or with few) memory allocation(s);