Bug 8581 - Parameter marshaling fails in DrawerMadness sample due to designer generation error
Summary: Parameter marshaling fails in DrawerMadness sample due to designer generation...
Alias: None
Product: MonoMac
Classification: Desktop
Component: Bindings ()
Version: GIT
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2012-11-23 19:23 UTC by Aaron Oneal
Modified: 2015-02-18 11:27 UTC (History)
3 users (show)

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

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Description Aaron Oneal 2012-11-23 19:23:01 UTC
1. Run the DrawerMadness sample
2. Click the "Open" button in the top-left

The app will fault with:

System.InvalidCastException: Cannot cast from source type to destination type.
  at (wrapper managed-to-native) object:__icall_wrapper_mono_object_castclass (object,intptr)
  at MonoMac.ObjCRuntime.NSObjectMarshaler`1[MonoMac.AppKit.NSButtonCell].MarshalNativeToManaged (IntPtr handle) [0x00021] in /mono/monomac/src/ObjCRuntime/NSObjectMarshaler.cs:35
  at (wrapper native-to-managed) object:[DrawerMadness.ParentWindowController:Void openLeftDrawer(MonoMac.AppKit.NSButtonCell)] (MonoMac.Foundation.NSObject,MonoMac.ObjCRuntime.Selector,MonoMac.AppKit.NSButtonCell)
  at (wrapper managed-to-native) MonoMac.AppKit.NSApplication:NSApplicationMain (int,string[])
  at MonoMac.AppKit.NSApplication.Main (System.String[] args) [0x0000a] in /mono/monomac/src/AppKit/NSApplication.cs:77
  at DrawerMadness.MainClass.Main (System.String[] args) [0x00005] in /monomac/samples/DrawerMadness/DrawerMadness/Main.cs:18

The problem is that Cocoa is passing an NSMatrix from the XIB as the sender but the tool that auto-generated the designer file output a method with an NSButtonCell sender instead. Looking at the original native sources to the sample, the messages just take an "id" as sender, so nothing more than an NSObject is required in this case.

The sample can be fixed by changing the protocol implementation to accept either NSMatrix or NSObject, but the tool that generated the designer file from the XIB needs to be fixed to generate this.
Comment 1 Timothy Risi 2015-02-18 11:27:25 UTC
This sample is working correctly now.