Bug 29242 - Registrar cannot build a signature for array of skeleton interfaces on device only
Summary: Registrar cannot build a signature for array of skeleton interfaces on device...
Alias: None
Product: iOS
Classification: Xamarin
Component: General ()
Version: XI 8.8.0
Hardware: PC Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Rolf Bjarne Kvinge [MSFT]
Depends on:
Reported: 2015-04-20 10:33 UTC by Emil
Modified: 2015-04-21 05:29 UTC (History)
3 users (show)

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

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Description Emil 2015-04-20 10:33:39 UTC
Compilation error when you bind objc protocols from native library to typed array.

1) Have protocols defined in objc static library, like this:

@protocol IBar;

@protocol IFoo <NSObject>

@property(nonatomic, strong) NSArray *bars;
@property(nonatomic, strong) id <IBar> currentBar;


2) Bind them to Xamarin project like this (I'm using skeleton empty interface IIBar here)

// @protocol IBar <NSObject>
[Protocol, Model]
[BaseType (typeof(NSObject))]
interface IBar
    // @required @property (nonatomic, strong) NSString * name;
    [Export ("name", ArgumentSemantic.Strong)]
    string Name { get; set; }
interface IIBar {}

// @protocol IFoo <NSObject>
[Protocol, Model]
[BaseType (typeof(NSObject))]
interface IFoo
    // @required @property (nonatomic, strong) NSArray * bars;
    [Export ("bars", ArgumentSemantic.Strong)]
    IIBar[] Bars { get; set; }

    // @required @property (nonatomic, strong) id<IBar> currentBar;
    [Export ("currentBar", ArgumentSemantic.Strong)]
    IIBar CurrentBar { get; set; }

3) Make implementations of these protocols

public class Foo : NSObject, IIFoo 

public class Bar : NSObject, IIBar

4) Build and run


MTOUCHTASK: error MT4111: The registrar cannot build a signature for type Binding.IIBar[]' in methodXTestApp.Foo.get_Bars`. Task "MTouchTask" execution -- FAILED

Xamarin.iOS version

Also this issue appears only when you deploy to device, on simulator everything works fine
Comment 1 Rolf Bjarne Kvinge [MSFT] 2015-04-21 05:29:11 UTC

maccore/master: 860650694dd5538ad050adf811bab6259c314282

In the meantime you can bind as an array of NSObject instead.