https://bugzilla.xamarin.com/show_bug.cgi?id=52570
In some cases you will find **static** members inside categories like in the following example:
```objc
@interface FooObject (MyFooObjectExtension)
+ (BOOL)boolMethod:(NSRange *)range;
@end
```
This will lead to an **incorrect** Category C# interface definition:
```csharp
[Category]
[BaseType (typeof (FooObject))]
interface FooObject_Extensions {
// Incorrect Interface definition
[Static]
[Export ("boolMethod:")]
bool BoolMethod (NSRange range);
}
```
This is incorrect because in order to use the `BoolMethod` extension you need an instance of `FooObject` but you are binding an ObjC **static** extension, this is a side effect due to the fact of how C# extension methods are implemented.
The only way to use the above definitions is by the following ugly code:
```csharp
(null as FooObject).BoolMethod (range);
```
The recommendation to avoid this is to inline the `BoolMethod` definition inside the `FooObject` interface definition itself, this will allow you to call this extension like it is intended `FooObject.BoolMethod (range)`.
```csharp
[BaseType (typeof (NSObject))]
interface FooObject {
[Static]
[Export ("boolMethod:")]
bool BoolMethod (NSRange range);
}
```
We will issue a warning (BI1117) whenever we find a `[Static]` member inside a `[Category]` definition. If you really want to have `[Static]` members inside your `[Category]` definitions you can silence the warning by using `[Category (allowStaticMembers: true)]` or by decorating either your member or `[Category]` interface definition with `[Internal]`.
Alex Soto