Bug 44980 - ActivityIndicator disappears when scrolling
Summary: ActivityIndicator disappears when scrolling
Alias: None
Product: Forms
Classification: Xamarin
Component: iOS ()
Version: 2.3.2
Hardware: PC Mac OS
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2016-10-03 16:07 UTC by Hrafn Loftsson
Modified: 2017-07-18 10:04 UTC (History)
7 users (show)

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

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Description Hrafn Loftsson 2016-10-03 16:07:11 UTC
In iOS, an ActivityIndicator, which is a ViewCell in a ListView, disappears when scrolling. When the ViewCell moves off the visible screen area and back in during scrolling, the indicator is no longer visible.

This has been reported before: https://forums.xamarin.com/discussion/62974/activityindicator-disappears-while-scrolling-in-the-listview

I have made a test project which shows this behaviour: https://github.com/KolibriDev/TestLayoutXaml

Note that this is only a problem in iOS - works in Droid and UWP.
Comment 1 adrianknight89 2016-11-01 02:45:25 UTC
I can confirm this issue.

At the moment, I can't figure out what's causing this. A workaround seems to be setting IsRunning to false and then true. Add this to GetCell of ListViewRenderer:

if ((cell as ViewCell).View is ActivityIndicator)
    ((cell as ViewCell).View as ActivityIndicator).IsRunning = false;
    ((cell as ViewCell).View as ActivityIndicator).IsRunning = true;

Of course, this is not even a hack. If the activity indicator is a child of another element or elements, then you'd need to recursively search for it.
Comment 2 adrianknight89 2016-11-01 07:39:40 UTC
See https://github.com/xamarin/Xamarin.Forms/pull/495
Comment 3 Rui Marinho 2017-04-06 18:27:00 UTC
Should be fixed on 2.3.5-pre1
Comment 5 Paul DiPietro [MSFT] 2017-07-11 18:11:42 UTC
Please upload a reproduction project displaying the issue when running on the 2.3.5-pre6 build.
Comment 6 Saurabh Paunikar 2017-07-18 10:01:48 UTC
fixed on version 2.3.5-pre6.
Comment 7 Saurabh Paunikar 2017-07-18 10:04:00 UTC
Verified on xamarin.form version
Hence marking this as verified.

ScreenCast link : https://www.screencast.com/t/lEP2M3gyPL