我的 View 模型当前包含以下代码:
private let project = RLMProject()
var projectToken: NotificationToken? = nil
projectToken = project.getDatabase()?.objects(RLMProject.self).observe { changes in ...
支持:
final class RLMProject: Object, Decodable, DatabaseLayer { ...
typealias T = RLMProject
}
protocol DatabaseLayer {
associatedtype T: Object
func getDatabase() -> Realm?
}
extension DatabaseLayer {
func getDatabase() -> Realm? {
do {
return try Realm(fileURL: userRealmFile)
} catch let error {
DDLogError("Database error: \(error)")
return nil
}
}
...
我想做getDatabase()
函数 private 但在封装通知闭包时遇到了麻烦, View 模型仍然可以为任何 <T: Object>
设置它,无需了解 Realm 的任何内部结构。
来自此的一些内容:
projectToken = project.getDatabase()?.objects(RLMProject.self).observe { [unowned self] ...
对此:
projectToken = project.setupNotificationToken { changes in ...
最佳答案
看来我已经成功了。
// Setup to observe Realm `CollectionChange` notifications
func setupNotificationToken(for observer: AnyObject, _ block: @escaping () -> Void) -> NotificationToken? {
if let database = self.getDatabase() {
return database.objects(T.self).observe { [weak observer] (changes: RealmCollectionChange) in
if observer != nil {
DDLogDebug("NotificationToken triggered on: \(observer!) for object: \(T.self)")
}
block()
}
} else {
return nil
}
}
示例:
projectToken = project.setupNotificationToken(for: self) { [unowned self] in
self.updateVC()
}
关于swift - 如何将 Realm 通知抽象为带有闭包的通用结构?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/51698740/