从Xamarin.iOS中的通用基类继承时出错

Question

I'm developing a Xamarin.iOS application which will connect to a web service via a RESTful API. I am currently writing the response and business objects for the API client layer, but I have run into a problem.

Consider the following two sample API results:

Successful

{  
  "data":{  
    "id":"gwaMR",
    "animated":false,
    "size":11762,
    "link":"http:\/\/i.imgur.com\/gwaMR.jpg"
  },
  "success":true,
  "status":200
}

Erroneous

{  
  "data":{  
    "error":"Unable to find an image with the id, vycVV",
    "request":"\/3\/image\/vycVV",
    "method":"GET"
  },
  "success":false,
  "status":404
}

Because both the successful data information as well as the error details both share the "data" key in their respective scenarios, I have written the following objects in C#:

public class BaseBusinessObject<D> where D:BaseBusinessObjectData
{
    public D Data { get; set; }
    public int Status { get; set; }
    public bool Success { get; set; }
}

public class BaseBusinessObjectData
{
    public string Error { get; set; }
    public string Method { get; set; }
    public string Request { get; set; }
}

public class ImageObject : BaseBusinessObject<ImageObjectData>
{
}

public class ImageObjectData : BaseBusinessObjectData
{
    public string ID { get; set; }
    public bool Animated { get; set; }
    public int Size { get; set; }
    public string Link { get; set; }
}

When making the API call (using automatic object deserialization with RestSharp ), I provide the object type ImageObject as the expected result type. However, I'm not actually able to get that far yet. When attempting to compile those response object types, I get the following error:

/Users/willseph/GitHub/Repos/AppName/API/API.cs(46,255+): Error CS0305: Using the generic type `AppName.BaseBusinessObject' requires `1' type argument(s) (CS0305)

However, when I take this same code and bring it into a standard C# library (still within Xamarin Studio), it compiles just fine.

As a workaround, I am able to remove generics from my code by using hiding and a new Data member:

public class BaseBusinessObject
{
    public BaseBusinessObjectData Data { get; set; }
    public int Status { get; set; }
    public bool Success { get; set; }
}

public class BaseBusinessObjectData
{
    public string Error { get; set; }
    public string Method { get; set; }
    public string Request { get; set; }
}

public class ImageObject : BaseBusinessObject
{
    public new ImageObjectData Data { get; set; }
}

public class ImageObjectData : BaseBusinessObjectData
{
    public string ID { get; set; }
    public string Link { get; set; }
    public int Size { get; set; }
    public bool Animated { get; set; }
}

This compiles fine and results in expected behavior. Does anyone have any insight on what may be causing this issue?

Answer 1

I tried adding a separate temporary file alongside my workaround containing the original erroneous classes (though renamed to not cause conflict), and it appears to be compiling.

I'm not sure what the issue was, but I suppose it was some strange fluke or anomaly caused by my computer.