Swift 错误 - Swift开发coredata出现Class not found解决办法

转载自http://blog.csdn.net/longhai0long/article/details/38379247

刚看swift开发IOS，在使用Core Data框架时遇到了一个问题，控制台打出的log 如下：

CoreData: warning: Unable to load class named 'CollectNews' for entity 'CollectNews'.  Class not found, using default NSManagedObject instead.

百思不得其解，后来在StackOverFlow上找到了一种解决办法，就是在Model类的开关加上这个的注解：

@objc(CollectNews) 

Demo的部分代码分享给大家，仅做参考：
Model类

import Foundation    

import CoreData  

@objc(CollectNews)    

class CollectNews: NSManagedObject {      

    @NSManaged var date: NSNumber    

    @NSManaged var newsId: NSNumber    

} 

AppDelegate类：

func application(application: UIApplication!, didFinishLaunchingWithOptions launchOptions: NSDictionary!) -> Bool {      

    insertData()    

    selectData()      

    return true    

}    

    

//插入数据    

func insertData(){      

    //取Entity对象    

    var collectNews = NSEntityDescription.insertNewObjectForEntityForName("CollectNews", inManagedObjectContext: self.managedObjectContext) as CollectNews    

    

    //对属性进行修改    

    collectNews.newsId = 12    

    collectNews.date = 20140805    

    

    //保存    

    if self.managedObjectContext.hasChanges{    

        self.managedObjectContext.save(nil)    

    }    

}    

    

//查询    

func selectData(){    

    //得request对象    

    var request = NSFetchRequest()    

    var entityQueue = NSEntityDescription.entityForName("CollectNews", inManagedObjectContext: self.managedObjectContext)    

    request.entity = entityQueue    

    var errorInfo:NSError?    

    //取结果集    

    var resultArr = self.managedObjectContext.executeFetchRequest(request, error: &errorInfo) as NSArray    

    

    println("----》\(resultArr.count)")    

    

    var temp = resultArr[0] as CollectNews    

    

    println("--->\(temp.newsId)")    

}