Bug 34014 - [iOS] ItemAppearing does not fire for ViewCell with custom renderer
Summary: [iOS] ItemAppearing does not fire for ViewCell with custom renderer
Status: RESOLVED ANSWERED
Alias: None
Product: Forms
Classification: Xamarin
Component: iOS ()
Version: 1.5.0
Hardware: PC Mac OS
: --- normal
Target Milestone: ---
Assignee: Bugzilla
URL:
Depends on:
Blocks:
 
Reported: 2015-09-16 14:28 UTC by John Miller [MSFT]
Modified: 2015-10-12 15:32 UTC (History)
2 users (show)

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


Attachments
Test Case (172.55 KB, application/x-rar)
2015-09-16 14:28 UTC, John Miller [MSFT]
Details
[HOW-TO-FIX] FastCell Implementation ItemAppearing iOS (181.00 KB, application/zip)
2015-10-12 15:32 UTC, Michael
Details


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Status:
RESOLVED ANSWERED

Description John Miller [MSFT] 2015-09-16 14:28:34 UTC
Created attachment 12915 [details]
Test Case

**Overview:**

   When using a custom ViewCellRenderer, the ListView.ItemAppearing event is not fired on iOS. 

**Steps to Reproduce:**

   1. Run the attached sample on an iOS simulator
   2. Scroll the list

**Actual Results:**

   The event is not raised. 

**Expected Results:**

   An alert should be displayed when the event fires.

**Build Date & Platform:**

   XF 1.5.0
   iOS 8.4

**Additional Information:**

   When using a ViewCell, ItemAppearing does fire. However, when that ViewCell has a custom renderer being used on iOS, it does not fire.
Comment 1 Michael 2015-10-12 15:32:35 UTC
Created attachment 13290 [details]
[HOW-TO-FIX] FastCell Implementation ItemAppearing iOS

After reviewing the sample, the Xamarin.Forms native cell implementation was being replaced with the GeorgeCook FastCell implementation. 

This is causing the ItemAppearing event to not bubble up on iOS because the mechanism for bubbling up that event lives in the Xamarin.Forms native cell implementation. 

The attached project displays how you can re-implement the ItemAppearing event for iOS with the FastCell implementation.