未保存swift couchebase lite CBL模型文档属性

我尝试创建CBLModel对象并将其保存在couchbase lite中。保存的文档没有错误，但从数据库检索文档时，文档的属性始终为零

//模型

class TestModelUser: CBLModel {
    var userName:NSString?
}

//创建并保存

let userModel:TestModelUser = TestModelUser(newDocumentInDatabase: db)
userModel.userName = "test user name 10"
userModel.setValue(NSStringFromClass(TestModelUser), ofProperty: "type")
let saved = userModel.save(&error)
if saved {
    println("saved")
}else{
    if let err:NSError = error {
        println(err.localizedDescription)
    }
}

//检索

let dbView:CBLView = db.viewNamed("userView")
dbView.setMapBlock({ (document, emit) -> Void in
    emit(document["_id"], document)
    if let docType = document["type"] as? String {
        if docType == NSStringFromClass(TestModelUser) {
            emit(document["_id"], document)
        }
    }
    }, version: "5")

let queryResult1:CBLQueryEnumerator = db.viewNamed("userView").createQuery().run(&error)
for row:CBLQueryRow in queryResult1.allObjects as [CBLQueryRow] {
    let user:TestModelUser = TestModelUser(forDocument: row.document)
    if let uName = user.userName {
        println(uName)
    }
}

而且user.userName总是为零，也许还有另一种保存文档的方法？

已解决

文档属性应具有@NSManaged修饰符：

class UserModel: CBLModel {
    @NSManaged var userName:NSString?
}

感谢jens（）