Bug 42426 - AVFoundation.AVAssetWriterInput - Unable to provide a "null" for AVVideoSettingsCompressed parameter
Summary: AVFoundation.AVAssetWriterInput - Unable to provide a "null" for AVVideoSetti...
Status: RESOLVED ANSWERED
Alias: None
Product: iOS
Classification: Xamarin
Component: Xamarin.iOS.dll ()
Version: XI 9.10 (C8)
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
URL:
Depends on:
Blocks:
 
Reported: 2016-07-08 13:00 UTC by RobertN
Modified: 2016-07-08 13:45 UTC (History)
3 users (show)

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

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RESOLVED ANSWERED

Description RobertN 2016-07-08 13:00:29 UTC
Xamarin.iOS Version: 9.9.0.288 

Unable to  create a `AVAssetWriterInput` that has a null for the `AVVideoSettingsCompressed` parameter due to ambiguous parameter, between AVVideoSettingsCompressed and AudioSetting since both parameters are named "mediaType".

Code Sample:

   var assetWriterInput = new AVAssetWriterInput(mediaType: AVMediaType.Video, outputSettings: null);

Error CS0121: 

The call is ambiguous between the following methods or properties:

`AVFoundation.AVAssetWriterInput.AVAssetWriterInput(string, AVFoundation.AudioSettings)' 
and 
`AVFoundation.AVAssetWriterInput.AVAssetWriterInput(string, AVFoundation.AVVideoSettingsCompressed)' 

Null/Nil is valid for this parameter:

>Passing nil for output settings instructs the input to pass through appended samples, doing no processing before they are written to the output file.  

https://developer.apple.com/library/ios/documentation/AVFoundation/Reference/AVAssetWriterInput_Class/index.html
Comment 1 Sebastien Pouliot 2016-07-08 13:45:51 UTC
This is a compiler error, not a runtime/API error. It simply means the compiler has more than one choice of overload where `null` could be legally used and needs help to decide which one to use.

Just provide enough information to the compiler, e.g.

> var assetWriterInput = new AVAssetWriterInput (
>    mediaType: AVMediaType.Video, 
>    outputSettings: (AudioSettings) null);

and it will work.