Bug 43299 - [UWP]ListView virtualization doesn't work when using Xamarin.Forms. And their solution.
Summary: [UWP]ListView virtualization doesn't work when using Xamarin.Forms. And their...
Status: RESOLVED DUPLICATE of bug 38948
Alias: None
Product: Forms
Classification: Xamarin
Component: Windows ()
Version: 2.3.2
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Bugzilla
URL:
Depends on:
Blocks:
 
Reported: 2016-08-12 09:56 UTC by qwerty2501
Modified: 2016-08-12 14:36 UTC (History)
2 users (show)

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

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Status:
RESOLVED DUPLICATE of bug 38948

Description qwerty2501 2016-08-12 09:56:51 UTC
ListView on UWP always work virtualization.
But ListView doesn't work virtualization when using Xamarin.Forms.
This problem was reported as bug.
https://bugzilla.xamarin.com/show_bug.cgi?id=38948

In order to solve, I recommend to delete <Setter Property="MinHeight" Value="0" /> from FormsListViewItem Style (Xamarin.Forms.Platform.UAP/Resources.xaml). 

Why deletion of MinHeight.
Becose virtualization ListView on UWP calculate the display range from ListViewItem's height.
And if ListViewItem's height is 0 when inserting, Virtualization ListView on UWP calculate from ListViewItem's MinHeight. ( Maybe, The height of theXamarin.Forms ListViewItem is 0 when inserting.)

In my research, ListView on UWP has strange specification as following:
1.If set ListViewItem's MinHeight by user, ListView on UWP calculate the display range from ListViewItem's MinHeight. ListView virtualization doesn't work.
2.If set ListViewItem's MinHeight by default, ListViewItem's MinHeight is 0. But The ListViewItem's Height isn't 0 When calculate the display range. ListView virtualization work.

For that reason, I recommend to delete MinHeight Setter.

# Environment Info
Visual Studio Community 2015 Update 38948
Windows 10 build 14393
Xamarin.Forms 2.3.2
Comment 1 Rui Marinho 2016-08-12 14:36:53 UTC

*** This bug has been marked as a duplicate of bug 38948 ***