持久存储在重度迁移中找不到迁移策略 class

Persistent Store can't find migration policy class in heavy migration

我收到此错误:

2015-12-29 03:13:41.603 n-back project[21345:474175] CoreData: error: -addPersistentStoreWithType:SQLite configuration:(null) URL:file:///Users/Nathan/Library/Developer/CoreSimulator/Devices/EC2C60E2-9FC8-40D7-B16F-15960AA6B42A/data/Containers/Data/Application/8F8132B0-76E9-491E-BA1B-27A5D78CE7D0/Documents/data.sqlite options:{
    NSMigratePersistentStoresAutomaticallyOption = 1;
} ... returned error Error Domain=NSCocoaErrorDomain Code=134110 "(null)" UserInfo={NSUnderlyingException=Couldn't create mapping policy for class named (BTRPolicy)} with userInfo dictionary {
    NSUnderlyingException = "Couldn't create mapping policy for class named (BTRPolicy)";
}
2015-12-29 03:13:41.608 n-back project[21345:474175] Unresolved error Error Domain=YOUR_ERROR_DOMAIN Code=9999 "Failed to initialize the application's saved data" UserInfo={NSLocalizedDescription=Failed to initialize the application's saved data, NSUnderlyingError=0x7b14eef0 {Error Domain=NSCocoaErrorDomain Code=134110 "(null)" UserInfo={NSUnderlyingException=Couldn't create mapping policy for class named (BTRPolicy)}}, NSLocalizedFailureReason=There was an error creating or loading the application's saved data.}, [NSLocalizedDescription: Failed to initialize the application's saved data, NSUnderlyingError: Error Domain=NSCocoaErrorDomain Code=134110 "(null)" UserInfo={NSUnderlyingException=Couldn't create mapping policy for class named (BTRPolicy)}, NSLocalizedFailureReason: There was an error creating or loading the application's saved data.]

在我看来,它在查找 class BTRPolicy 时遇到了问题。它存在于名为 BTRPolicy 的文件 BTRPolicy 中。它被正确地子 classed 并在实用程序窗格的自定义策略选择中被引用为 "BTRPolicy"。有什么想法吗?

以防其他人遇到此问题并且这与您的 google 搜索匹配:我想通了,出于某种原因,自定义策略现在需要以模块名称为前缀。