I'm trying to add a service to the Finder's context menu using this class:

```
public class Service {
  public func handleServices(pboard:NSPasteboard, userData:String, error:UnsafeMutableBufferPointer<String>) {  // not sure about the correct parameters
    if (pboard.types?.contains(NSFilenamesPboardType) != nil) {
      let fileArray = pboard.propertyListForType(NSFilenamesPboardType)
      print(fileArray)
    }
  }

  init () {
    NSApp.servicesProvider = self
    NSUpdateDynamicServices()
  }
}

```

The service is announced in info.plist as follows:

```
<key>NSServices</key>
<array>
    <dict>
        <key>NSMenuItem</key>
        <dict>
            <key>default</key>
            <string>Service Handling Demo</string>
        </dict>
        <key>NSMessage</key>
        <string>handleServices</string>
        <key>NSPortName</key>
        <string>services</string>
        <key>NSSendTypes</key>
        <array>
            <string>NSFilenamesPboardType</string>
        </array>
    </dict>
</array>

```

Finally I have turned on the service in System Preferences/Keyboard/Shortcuts. So I see the service and can call it. But all I get when calling it is 

> 
> Cannot find service provider for selector handleServices:userData:error: or handleServices:: for service handleServices
> 
> 
>