Question

我有一个绑定obj-c对象的类

public unsafe partial class CUSTOMER_INFO : NSObject {

        [Export ("signature", ArgumentSemantic.Retain)]
        get {
            NSData ret;
            if (IsDirectBinding) {
                ret =  Runtime.GetNSObject<NSData> (global::ApiDefinition.Messaging.IntPtr_objc_msgSend (this.Handle, Selector.GetHandle ("signature")));
            } else {
                ret =  Runtime.GetNSObject<NSData> (global::ApiDefinition.Messaging.IntPtr_objc_msgSendSuper (this.SuperHandle, Selector.GetHandle ("signature")));
            }
            if (!IsNewRefcountEnabled ())
                __mt_Signature_var = ret;
            return ret;
        }

        [Export ("setSignature:", ArgumentSemantic.Retain)]
        set {
            if (value == null)
                throw new ArgumentNullException ("value");
            if (IsDirectBinding) {
                global::ApiDefinition.Messaging.void_objc_msgSend_IntPtr (this.Handle, Selector.GetHandle ("setSignature:"), value.Handle);
            } else {
                global::ApiDefinition.Messaging.void_objc_msgSendSuper_IntPtr (this.SuperHandle, Selector.GetHandle ("setSignature:"), value.Handle);
            }
            if (!IsNewRefcountEnabled ())
                __mt_Signature_var = value;
        }
}

但是当我声明它并将其传递给方法（在ios绑定库中）时，我得到了已知的异常

System.ExecutionEngineException：尝试JIT编译方法运行时'CUSTOMER_INFO：set_Signature（Foundation.NSData）' 只有--aot - 。有关详细信息，请参阅http://docs.xamarin.com/ios/about/limitations。

用户@SushiHangover建议后

更新在我生成的代码中的iOS绑定库项目中，我尝试了这种解决方法：

[Register("CUSTOMER_INFO", true)]
//public unsafe partial class CUSTOMER_INFO : NSObject {
public unsafe partial class CUSTOMER_INFO_GENERIC<T> : NSObject where T : NSObject
{
    [CompilerGenerated]
    static readonly IntPtr class_ptr = Class.GetHandle ("CUSTOMER_INFO");

    public override IntPtr ClassHandle { get { return class_ptr; } }

    [CompilerGenerated]
    [EditorBrowsable (EditorBrowsableState.Advanced)]
    [Export ("init")]
    public CUSTOMER_INFO_GENERIC () : base (NSObjectFlag.Empty)
    {
        IsDirectBinding = GetType ().Assembly == global::ApiDefinition.Messaging.this_assembly;
        if (IsDirectBinding) {
            InitializeHandle (global::ApiDefinition.Messaging.IntPtr_objc_msgSend (this.Handle, global::ObjCRuntime.Selector.GetHandle ("init")), "init");
        } else {
            InitializeHandle (global::ApiDefinition.Messaging.IntPtr_objc_msgSendSuper (this.SuperHandle, global::ObjCRuntime.Selector.GetHandle ("init")), "init");
        }
    }

    [CompilerGenerated]
    [EditorBrowsable (EditorBrowsableState.Advanced)]
    protected CUSTOMER_INFO_GENERIC(NSObjectFlag t) : base (t)
    {
        IsDirectBinding = GetType ().Assembly == global::ApiDefinition.Messaging.this_assembly;
    }

    [CompilerGenerated]
    [EditorBrowsable (EditorBrowsableState.Advanced)]
    protected internal CUSTOMER_INFO_GENERIC(IntPtr handle) : base (handle)
    {
        IsDirectBinding = GetType ().Assembly == global::ApiDefinition.Messaging.this_assembly;
    }

    // other methods....
    // .................

    [CompilerGenerated]
    object __mt_Signature_var;
    [CompilerGenerated]
    public virtual NSData SignatureNoJit {
        [Export ("signature", ArgumentSemantic.Retain)]
        get {
            NSData ret;
            if (IsDirectBinding) {
                ret =  Runtime.GetNSObject<NSData> (global::ApiDefinition.Messaging.IntPtr_objc_msgSend (this.Handle, Selector.GetHandle ("signature")));
            } else {
                ret =  Runtime.GetNSObject<NSData> (global::ApiDefinition.Messaging.IntPtr_objc_msgSendSuper (this.SuperHandle, Selector.GetHandle ("signature")));
            }
            if (!IsNewRefcountEnabled ())
                __mt_Signature_var = ret;
            return ret;
        }

        [Export ("setSignature:", ArgumentSemantic.Retain)]
        set {
            if (value == null)
                throw new ArgumentNullException ("value");
            if (IsDirectBinding) {
                global::ApiDefinition.Messaging.void_objc_msgSend_IntPtr (this.Handle, Selector.GetHandle ("setSignature:"), value.Handle);
            } else {
                global::ApiDefinition.Messaging.void_objc_msgSendSuper_IntPtr (this.SuperHandle, Selector.GetHandle ("setSignature:"), value.Handle);
            }
            if (!IsNewRefcountEnabled ())
                __mt_Signature_var = value;
        }
    }

    [CompilerGenerated]
    protected override void Dispose (bool disposing)
    {
        base.Dispose (disposing);
        if (Handle == IntPtr.Zero) {
            __mt_Signature_var = null;
        }
    }
}

public class CUSTOMER_INFO_NOJIT : CUSTOMER_INFO_GENERIC<NSData>
{
    // A specialized subclass and this is passed to your ObjC-based method
}

但是当我打电话时

NSData tmp = NSData.FromArray(new byte[] { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF });
CUSTOMER_INFO_NOJIT CustomerInfo = new CUSTOMER_INFO_NOJIT();
CustomerInfo.CardHolderEmail = CardHolderEMail;
CustomerInfo.CardHolderMobile = CardHolderMobilePhone;
CustomerInfo.SignatureNoJit = tmp;

我再次得到这个例外：

System.ExecutionEngineException：尝试JIT编译方法 “CUSTOMER_INFO_GENERIC`1：set_SignatureNoJit （Foundation.NSData）'在使用--aot-only运行时。看到 http://docs.xamarin.com/ios/about/limitations了解更多信息。

任何人都可以建议我一个解决方法/模式来避免这种异常？谢谢！

Lewix

Answer 1

（我可能需要更多的咖啡......所以拿一粒盐......： - ）

此：

public unsafe partial class CUSTOMER_INFO : NSObject {
   ~~~~
}

变为：

public unsafe partial class CUSTOMER_INFO_GENERIC<T> : NSObject where T : NSObject {
  ~~~~
}

class CUSTOMER_INFO : CUSTOMER_INFO_GENERIC<NSData>
{
  // A specialized subclass and this is passed to your ObjC-based method
}

因此this和set返回中的get可以解析为NSData与NSObject，并且不需要jitting并且编译器已创建/解决了这些课程......

避免Xamarin iOS

1 个答案: