Bug 41194 - All CarouselPage Children call Appearing and onAppearing on CarouselPage creation.
Summary: All CarouselPage Children call Appearing and onAppearing on CarouselPage crea...
Alias: None
Product: Forms
Classification: Xamarin
Component: Forms ()
Version: 2.2.0
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2016-05-19 18:50 UTC by dpedrinha
Modified: 2016-08-09 13:45 UTC (History)
2 users (show)

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

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Description dpedrinha 2016-05-19 18:50:13 UTC
Create any CarouselPage and add some Children.

When opening the CarouselPage all children will call Appearing and OnAppearing even though only one is showing.
Comment 1 dpedrinha 2016-05-19 18:56:33 UTC
And isVisible is true for all children too.
Comment 2 Rui Marinho 2016-08-05 10:57:16 UTC
Hi, this is not a issue, this depends in how the native platform works, since the ContentPages aren't virtualised they are loaded.

IsVisible is also never changed in any platform.
Comment 3 dpedrinha 2016-08-09 04:57:23 UTC
And shouldn't it? 

I managed to easily virtualise the page load in the PCL project, but IsVisible is out of my reach.

This behavior is not expected.
Comment 4 Rui Marinho 2016-08-09 10:30:12 UTC
Hi we moved our efforts to CarrouselView instead, you should use that for virtualisation support. 

Comment 5 dpedrinha 2016-08-09 13:45:10 UTC
I'm sorry but I fixed this problem with almost no effort with less than 20 lines of code. And it's working perfectly and smoothly for infinite number of scrollable pages with heavy layout calculations and images with more than 1mb in each page.

And the CarrouselView doesn't work the same way. It's good for showing a caroussel of Views but not entire scrollable pages.

But it's ok. It's working fine. My main concern is about the IsVisible property not working as it should. Do you plan to fix it? I mean, IsVisible is very important for many things. And it's something that I cant' fix with code.