Bug 3819 - UIView.ConvertRectFromView optional nil parameter not supported
Summary: UIView.ConvertRectFromView optional nil parameter not supported
Alias: None
Product: iOS
Classification: Xamarin
Component: Xamarin.iOS.dll ()
Version: 5.2
Hardware: PC Windows
: --- normal
Target Milestone: Untriaged
Assignee: Sebastien Pouliot
Depends on:
Reported: 2012-03-09 03:40 UTC by info
Modified: 2012-03-09 09:47 UTC (History)
2 users (show)

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

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Description info 2012-03-09 03:40:13 UTC
According to the official Apple documentation of UIView convertRect:fromWindow:

    The view with rect in its coordinate system. If view is *nil*, this method instead converts from window base coordinates. Otherwise, both view and the receiver must belong to the same UIWindow object."

However, if I pass null for the fromView parameter in MonoTouch I get an immediate ArgumentNullException. This makes it impossible to covert from window base coordinates.

The same bug definitely exists in UIWindow.ConvertRectFromView and probably also in all other [UIWindow|UIView].Convert[Point|Rect][To|From][Window|View] methods. 

In any of these methods the second parameter may be legally nil. Therefore MonoTouch should allow passing null for this parameter and not throw an ArgumentNullException.
Comment 1 Sebastien Pouliot 2012-03-09 09:30:18 UTC
Some of them already allows `null` while other throws an exception. I'll review/fix them.
Thanks for the report.
Comment 2 Sebastien Pouliot 2012-03-09 09:47:51 UTC
ConvertPoint* were already correct.
ConvertRect* were missing a [NullAllowed] attribute.

Fixed in master a7577f9f67726d514e8e330ac71dc601b210c40b
Fixed in 5.2-series 6bd36e6657f3ffc4dae3735d6a6339e6be185718

QA: unit tests added