Bug 13792 - Trying to use Content property of NSTreeController causes InvalidCastException
Summary: Trying to use Content property of NSTreeController causes InvalidCastException
Alias: None
Product: MonoMac
Classification: Desktop
Component: Bindings ()
Version: unspecified
Hardware: PC Mac OS
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2013-08-06 19:47 UTC by David Lechner
Modified: 2014-06-19 21:07 UTC (History)
3 users (show)

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

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Description David Lechner 2013-08-06 19:47:31 UTC
For some reason, the Content property of NSTreeController is typed as NSTreeController. From apple's docs, it looks like it should just be NSObject[1]. As a result, if you try to use this property, you get an InvalidCastException.

I could not come up with a simple sample to reproduce the error, but if needed, I could make a small project and attach it to the bug.

[1] <https://developer.apple.com/library/mac/documentation/Cocoa/Reference/ApplicationKit/Classes/NSTreeController_Class/Reference/Reference.html#//apple_ref/occ/instm/NSTreeController/setContent:>
Comment 1 Miguel de Icaza [MSFT] 2014-02-11 23:29:05 UTC

Comment 2 xamarin 2014-06-19 21:07:33 UTC
The most recent stable installers (as of June 18, 2014) still have this problem for NSTreeController (at least in MonoMac).

As an easy workaround, cast to NSObjectController, then access its Content property instead.