The applying that I wish to develop is made up of two threads.

1st thread (Scanner)

• I insert the perceived information within the database
• I present the info in a desk

2nd thread (Sender)

• I take the info from the database (max 100) and ship it to our server
• if the info has been accurately despatched I delete it

Every thread should run each n seconds and this worth may be modified from the settings.

For the development of the database I used the next library:
https://github.com/stephencelis/SQLite.swift

For the development of the threads I used:

class RepeatingTimer {

    let timeInterval: TimeInterval

    init(timeInterval: TimeInterval) {
        self.timeInterval = timeInterval
    }

    non-public lazy var timer: DispatchSourceTimer = {
        let t = DispatchSource.makeTimerSource()
        t.schedule(deadline: .now() + self.timeInterval, repeating: self.timeInterval)
        t.setEventHandler(handler: { [weak self] in
            self?.eventHandler?()
        })
        return t
    }()

    var eventHandler: (() -> Void)?

    non-public enum State {
        case suspended
        case resumed
        //case canceled
    }

    non-public var state: State = .suspended

    deinit {
        timer.setEventHandler {}
        timer.cancel()

        resume()
        eventHandler = nil
    }

    func resume() {
        if state == .resumed {
            return
        }
        state = .resumed
        timer.resume()
    }

    func droop() {
        if state == .suspended {
            return
        }
        state = .suspended
        timer.droop()
    }
    /*
    func finish() {
        print("Elimino il Processo")
        if state == .canceled {
            print("state == .canceled")
            return
        }
        state = .canceled
        print("Portato lo stato a canceled")
        timer.cancel()
    }*/
}

My issues are:

• How one can cease threads to restart them with the brand new worth (n. Seconds)?
• The applying breaks after a while because it alerts to me that the database is blocked due to make use of by one other useful resource

The library for the connection / creation of the Database appears to me very legitimate, I believe my drawback with the implementation of threads.

The applying can even should run on variations previous to iOS 13.
Thanks for collaboration