Bug 13917 - CVPixelFormatDescription.AllTypes crashing due to wrong return type
Summary: CVPixelFormatDescription.AllTypes crashing due to wrong return type
Alias: None
Product: iOS
Classification: Xamarin
Component: Xamarin.iOS.dll ()
Version: 6.4.0
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Sebastien Pouliot
Depends on:
Reported: 2013-08-12 08:54 UTC by kissling
Modified: 2013-08-12 14:03 UTC (History)
2 users (show)

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

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Description kissling 2013-08-12 08:54:57 UTC
The property CVPixelFormatDescription.AllTypes crashes when accessed, as the result type of the corresponding native function is NSNumber[] instead of NSDictionary[].

The corresponding native function is listed here:


Note that the documentation is wrong. 

Apple states:
An array of Core Foundation dictionaries, each containing a pixel format description. See “Pixel Format Description Keys” for a list of keys relevant to the format description.

However, when invoked and checking the type of the result objects, it is revealed that the NSArray consists of NSNumber which can subsequently be passed to CVPixelFormatDescriptionCreateWithPixelFormatType in order to retrieve additional information.

The following code succeeds, confirming the wrong documentation:

            var types = NSArray.ArrayFromHandle<NSNumber>(CVPixelFormatDescriptionArrayCreateWithAllPixelFormatTypes(IntPtr.Zero));
            foreach (var t in types)
                NSDictionary d = CVPixelFormatDescription.Create(t.IntValue);
                Console.WriteLine(" {0}", d);
Comment 1 Sebastien Pouliot 2013-08-12 09:52:22 UTC
Good catch!
Comment 2 Sebastien Pouliot 2013-08-12 14:03:57 UTC
Fixed in master 7bfbefa3ad135ca6c76a63434d572b71531d2ef2
I reported the documentation issue to Apple.