swift - RealmSwift 也需要 Realm

Question

我正在将一个项目迁移到 Swift 3，并且在使用 RealmSwift (2.6.1) 和 Genome (3.2.0) 时遇到了一些问题。我在 Xcode 中遇到 Realm 错误，提示我需要这些初始化:

required convenience init(realm: RLMRealm, schema: RLMObjectSchema) {
    self.init(realm: realm, schema: schema)
}

required convenience init(value: Any, schema: RLMSchema) {
    self.init(value: value, schema: schema)
}

但是，除了 RealmSwift 之外，这还需要导入 Realm，并且当我的类被初始化时，它试图使用 RLMRealm 而不是 Realm。警告说“必需的”初始值设定项“init(realm:schema:)”必须由“Object”的子类提供，但必需的 init 使用 RLMRealm 而不是 Realm 有什么建议吗？

我也在使用 Genome，它需要这个初始化，这就是为什么 Realm 首先要求初始化器:

required convenience init(node: Node, in context: Context) throws {
    self.init()
}

所以 init 看起来像这样:

class BaseModel : RealmSwift.Object, MappableBase, Identifiable {

required init() {
    super.init()
}

required convenience init(node: Node, in context: Context) throws {
    self.init()
}

required convenience init(realm: RLMRealm, schema: RLMObjectSchema) {
    self.init(realm: realm, schema: schema)
}

required convenience init(value: Any, schema: RLMSchema) {
    self.init(value: value, schema: schema)
}

在没有任何这些初始化程序的情况下，在 Swift 2.3(使用相应的 Swift 2.3 版本的 Realm 和 Genome)中一切正常，但现在它不工作了。

整个模型:

import RealmSwift
import Genome
import Realm

protocol Identifiable {
    var identifier: String { get set }
}


class BaseModel : RealmSwift.Object, MappableBase, Identifiable {

required init() {
    super.init()
}

required convenience init(node: Node, in context: Context) throws {
    try self.init(node: node, in: context)
}

required convenience init(realm: RLMRealm, schema: RLMObjectSchema) {
    self.init(realm: realm, schema: schema)
}

required convenience init(value: Any, schema: RLMSchema) {
    self.init(value: value, schema: schema)
}

dynamic var identifier = ""
dynamic var updatedAt: Date?

override static func primaryKey() -> String {
    return "identifier"
}

static func newInstance(_ node: Node, context: Context = EmptyNode) throws -> Self {
    let map = Map(node: node, in: context)
    let new = self.init()
    try new.sequence(map)
    return new
}

func sequence(_ map: Map) throws {
    switch map.type {
    case .fromNode:
        if self.identifier.isEmpty {
            // only map id if there isn't one, otherwise Realm complains about modified primaryKey
            try self.identifier <~ map["id"]
        }
        updatedAt = Date()
    case .toNode:
        if !self.identifier.isEmpty {
            try self.identifier ~> map["id"]
        }
    }
}

func objectRepresentation() -> [String : AnyObject] {
    if let result = try? self.toObject() {
        return result as? [String : AnyObject] ?? [:]
    } else {
        return [:]
    }
}

static func objectInRealm(_ realm: Realm, identifier: String?) -> Self? {
    if let identifier = identifier {
        return realm.object(ofType: self, forPrimaryKey: identifier)
    } else {
        return nil
    }
}

static func createOrFindObject(inRealm realm: Realm, identifier: String) -> Self {
    if let foundObject = realm.object(ofType: self, forPrimaryKey: identifier) {
        return foundObject
    } else {
        return realm.create(self, value: ["identifier" : identifier], update: false)
    }
}
}

Answer 1

不需要重写init(realm:schema:)和init(realm:schema:)，只定义方便需要的init(node :in:) 像下面这样抛出。

class BaseModel : RealmSwift.Object, MappableBase, Identifiable {

    convenience required init(node: Node, in context: Context) throws {
        try self.init(node: node, in: context)
    }

    ...

}