Question

看来好像！我尝试了一切，但我无法做到。

我每2分钟从数据库中获取数据并在API中发布数据。我的应用程序每2分钟就会停留一段时间。原因是当我从数据库获取时间应用程序卡住的数据时。我必须在后台做。

这是我的代码正在运行，但应用程序是Stuck

 func getObjects(type: Object.Type) -> Results<Object>? {

            //... *****************************
            //...code is working but app is stuck 

            return realm.objects(type)
        }

 if let list = realm.getObjects(type: AssignedCalendars.self)?.filter("isRemove == \(true) AND isSynced == \(false)").toArray(ofType: AssignedCalendars.self) {
                if list.count > 0 {
                    list.forEach({ (calendar) in
                        let calendar_json = [APIKey.event_id : calendar.event_id, APIKey.offlineId: calendar.offlineId, APIKey.calendar_id: calendar.calendar_id.toArray(ofType: Int.self)] as [String: Any]
                        removedCalendars.append(calendar_json)
                    })
                }
                offlineRemovedCalendars.append(contentsOf: list)
                eventData[APIKey.calendar_removelist] = removedCalendars
            }

尝试1。尝试在后台运行代码我必须尝试使用调度队列

func getObjects(type: Object.Type) -> Results<Object>? {

            //... *****************************
            //...code is working but app is stuck 

            return realm.objects(type)
        }


 DispatchQueue.main.async(execute: {
        if let list = realm.getObjects(type: AssignedCalendars.self)?.filter("isRemove == \(true) AND isSynced == \(false)").toArray(ofType: AssignedCalendars.self) {

            DispatchQueue.global().async {
            if list.count > 0 {
                list.forEach({ (calendar) in
                    let calendar_json = [APIKey.event_id : calendar.event_id, APIKey.offlineId: calendar.offlineId, APIKey.calendar_id: calendar.calendar_id.toArray(ofType: Int.self)] as [String: Any]
                    removedCalendars.append(calendar_json)
                })
            }
            offlineRemovedCalendars.append(contentsOf: list)
            eventData[APIKey.calendar_removelist] = removedCalendars

          } //.. end bac que
        }
        })//... main que

尝试2.在后台使用领域但是我不知道如何使用这种方法

extension Realm {



    func writeAsync<T : ThreadConfined>(obj: T, errorHandler: @escaping ((_ error : Swift.Error) -> Void) = { _ in return }, block: @escaping ((Realm, T?) -> Void)) {
        let wrappedObj = ThreadSafeReference(to: obj)
        let config = self.configuration
        DispatchQueue(label: "background").async {
            autoreleasepool {
                do {
                    let realm = try Realm(configuration: config)
                    let obj = realm.resolve(wrappedObj)

                    try realm.write {
                        block(realm, obj)
                    }
                }
                catch {
                    errorHandler(error)
                }
            }
        }
    }
}

尝试3.找到一个解决方案，但它不起作用。它没有以良好的方式执行。 IT的ADD方法，而不是获取

var usersRef: ThreadSafeReference<Results<User>>?
DispatchQueue.global().async {
    autoreleasepool{
        let realm = try! Realm()
        try! realm.write {
            realm.add(users)
        }
        usersRef = ThreadSafeReference(to: users)
    }
}

Answer 1

TRY 1不起作用，因为您无法在线程之间传递Realm对象引用。你需要做什么：

var realmConig: Realm.Configuration = // your config - store it globally

// Now fetch the data
DispatchQueue(label: "background").async {
    // Define a new Realm object inside async thread
    let realm = try! Realm(configuration: realmConfig)
    // now fetch your objects
    let objects = realm.objects(Object.self)
    // From here you can perform actions with the objects
    // i.e. transform if to json format and submit via API
}

警告：为了在后台线程之外使用objects，您必须先将它们转换为ThreadSafeReference数组。但就我的理解你的目标而言，并不需要你的具体案例。

后台线程中的swift Realm然后app崩溃

1 个答案: