错误：“此类不符合键值编码标准”-对于任何键

Question

我正在将对象保存在Core Data模型中，但是我发现该密钥与任何密钥都不兼容。

我试图反转键的顺序，但是我要解决的是，我试图更改nome o实体，但是也没有用。

        let mediaEntity = NSEntityDescription.entity(forEntityName: 
"Media", in: managedContext)
        mediaEntity?.setValue(showMediaModel.popularity, forKey: "popularity")
        mediaEntity?.setValue(showMediaModel.title, forKey: "title")
        mediaEntity?.setValue(showMediaModel.type.rawValue, forKey: "type")
        mediaEntity?.setValue(showMediaModel.id, forKey: "id")

        do {
            try managedContext.save()
        } catch let error as NSError {
            print("Could not save. \(error), \(error.userInfo)")
        }

核心数据模型：

详细的消息错误是：

Terminating app due to uncaught exception 'NSUnknownKeyException', 
reason: '[<NSEntityDescription 0x6000008c02c0> 
setValue:forUndefinedKey:]: this class is not key value coding- 
compliant for the key popularity.'

在启动项目后，我按照以下教程添加了核心数据：https://welcm.uk/blog/adding-core-data-to-an-existing-project-in-xcode-10-swift-4

Answer 1

检查您的xcdatamodel文件，并确保“ popularity”的拼写与出现错误的行中的拼写匹配。

Answer 2

我忘记创建对象了。

if let mediaEntity = NSEntityDescription.entity(forEntityName: "Media", in: managedContext) {
    let newEntity = NSManagedObject(entity: mediaEntity, insertInto: managedContext)
    newEntity.setValue(showMediaModel.popularity, forKey: "popularity")
    newEntity.setValue(showMediaModel.title, forKey: "title")
    newEntity.setValue(showMediaModel.type.rawValue, forKey: "type")
    newEntity.setValue(showMediaModel.id, forKey: "id")

    do {
        try managedContext.save()
    } catch let error as NSError {
        print("Could not save. \(error), \(error.userInfo)")
    }
}