iOS核心数据:为属性指定值时出错
这是MyApp.xcdatamodeld,非常简单: _ 这是与实体关联的类:iOS核心数据:为属性指定值时出错,ios,swift,core-data,xcode6,Ios,Swift,Core Data,Xcode6,这是MyApp.xcdatamodeld,非常简单: _ 这是与实体关联的类: class LogItem: NSManagedObject { @NSManaged var title: String @NSManaged var itemText: String @NSManaged var itemRank: String } 下面是导致错误的代码: let newItem = NSEntityDescription.insertNewObjectForEnt
class LogItem: NSManagedObject {
@NSManaged var title: String
@NSManaged var itemText: String
@NSManaged var itemRank: String
}
下面是导致错误的代码:
let newItem = NSEntityDescription.insertNewObjectForEntityForName("LogItem", inManagedObjectContext: self.managedObjectContext!) as! LogItem
newItem.title = "the title of the item"
newItem.itemText = "je suis chérif"
newItem.itemRank = "2" // this line causes an error !
*** Terminating app due to uncaught exception 'NSInvalidArgumentException',
reason: '-[MyApp.LogItem setItemRank:]: unrecognized selector sent to instance 0x155a8e30'
最后是错误:
let newItem = NSEntityDescription.insertNewObjectForEntityForName("LogItem", inManagedObjectContext: self.managedObjectContext!) as! LogItem
newItem.title = "the title of the item"
newItem.itemText = "je suis chérif"
newItem.itemRank = "2" // this line causes an error !
*** Terminating app due to uncaught exception 'NSInvalidArgumentException',
reason: '-[MyApp.LogItem setItemRank:]: unrecognized selector sent to instance 0x155a8e30'
我做错了什么?当我处理核心数据对象时,我使用以下代码行创建实体
let logEntity = NSEntityDescription.entityForName("LogItem", inManagedObjectContext: self.managedObjectContext!)
let newItem = LogItem(entity: logEntity!, insertIntoManagedObjectCntext: self.managedObjectContext!)
newItem.title = "the title of the item"
newItem.itemText = "je suis chérif"
newItem.itemRank = "2"
然后保存上下文。我看不到明显的错误。如果删除这一行,代码是否可以正常运行?您确定在创建类登录项后没有更改核心数据模型或创建其他版本吗?我在创建类登录项后修改了它。我清理了项目,现在它工作了!所以实际上根本没有错误。