Bug 38886 - AVCaptureMetadataOutput.SetDelegate can not set objectsDelegate to null
Summary: AVCaptureMetadataOutput.SetDelegate can not set objectsDelegate to null
Alias: None
Product: iOS
Classification: Xamarin
Component: Xamarin.iOS.dll ()
Version: XI 9.4 (iOS 9.2)
Hardware: PC Mac OS
: Normal normal
Target Milestone: (C7)
Assignee: Bugzilla
Depends on:
Reported: 2016-02-18 18:43 UTC by Jon Goldberger [MSFT]
Modified: 2016-05-19 14:44 UTC (History)
3 users (show)

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

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Description Jon Goldberger [MSFT] 2016-02-18 18:43:02 UTC
## Description

Apple's docs [1] say that nil can be supplied for the `objectsDelegate` parameter of the `AVCaptureMetadataOutput.SetDelegate`. However passing null to this method in XI causes an exception to be thrown [2].

[1] https://developer.apple.com/library/prerelease/ios/documentation/AVFoundation/Reference/AVCaptureMetadataOutput/index.html#//apple_ref/occ/instm/AVCaptureMetadataOutput/setMetadataObjectsDelegate:queue:

>System.ArgumentNullException: Value cannot be null.
>Parameter name: objectsDelegate

## Steps to reproduce

1. Create a new iOS project from template and add the following code to the AppDelegate's FinishedLaunching method:
`var x = new AVCaptureMetadataOutput ();
x.SetDelegate (null, null);`

2. Deploy the app. 

Expected result: Able to pass null to the above method.

Actual result: Exception above thrown. 

## Environment

=== Xamarin Studio ===

Version 5.10.2 (build 56)
Installation UUID: 964c531b-d928-456b-a9ae-e1f82266b360
	Mono 4.2.2 (explicit/996df3c)
	GTK+ 2.24.23 (Raleigh theme)

	Package version: 402020030

=== Xamarin.Profiler ===

Location: /Applications/Xamarin Profiler.app/Contents/MacOS/Xamarin Profiler

=== Apple Developer Tools ===

Xcode 7.2.1 (9548.1)
Build 7C1002

=== Xamarin.iOS ===

Version: (Business Edition)
Hash: 962a050
Branch: master
Build date: 2016-01-29 16:59:11-0500

=== Xamarin.Mac ===

Version: (Business Edition)

=== Xamarin.Android ===

Version: (Business Edition)
Android SDK: /Users/apple/Library/Developer/Xamarin/android-sdk-mac_x86
	Supported Android versions:
		4.0.3 (API level 15)
		4.1   (API level 16)
		4.2   (API level 17)
		4.3   (API level 18)
		4.4   (API level 19)
		5.0   (API level 21)
		5.1   (API level 22)
		6.0   (API level 23)

SDK Tools Version: 24.4.1
SDK Platform Tools Version: 23.1
SDK Build Tools Version: 23.0.2

Java SDK: /usr
java version "1.7.0_79"
Java(TM) SE Runtime Environment (build 1.7.0_79-b15)
Java HotSpot(TM) 64-Bit Server VM (build 24.79-b02, mixed mode)

=== Xamarin Android Player ===

Version: 0.6.5
Location: /Applications/Xamarin Android Player.app

=== Xamarin Inspector ===

Hash: 45b35bb
Branch: master
Build date: Thu Jan 14 18:53:32 UTC 2016

=== Build Information ===

Release ID: 510020056
Git revision: bb74ff467c62ded42b7b7ac7fdd2edc60f8647b0
Build date: 2016-01-26 16:24:41-05
Xamarin addins: 8b797d7ba24d5abab226c2cf9fda77f666263f1b
Build lane: monodevelop-lion-cycle6-c6sr1

=== Operating System ===

Mac OS X 10.11.3
Darwin Jons-iMac.local 15.3.0 Darwin Kernel Version 15.3.0
    Thu Dec 10 18:40:58 PST 2015
    root:xnu-3248.30.4~1/RELEASE_X86_64 x86_64
Comment 1 Sebastien Pouliot 2016-02-19 02:50:43 UTC
Fixed in maccore/master 3753140f459c0a4f22810665228c55755d23293e

QA: unit test added in same commit
Comment 2 Atin 2016-05-19 14:44:24 UTC
Reproduce Status:

I have checked this issue with monotouch- and able to reproduce the reported behavior given in the bug description.

Screencast: http://www.screencast.com/t/E0IX7RfuIV


Verified Status: 

I have checked this issue with latest build of Cycle 7 i.e. xamarin.ios- and now this issue is working fine.

Screencast: http://www.screencast.com/t/vBzy2X9Wk

Hence I am closing this issue.