[OS - 🍎 macOS] DispatchSourceTimer

🗂 DispatchSourceTimer

protocol DispatchSourceTimer

 

[영문]

A dispatch source that submits the event handler block based on a timer. You do not adopt this protocol in your objects. Instead, use the makeTimerSource(flags:queue:) method to create an object that adopts this protocol.

 

[국문]

Dispatch Source는 타이머를 기반으로 이벤트 핸들러 코드 블럭을 제출합니다. 또한, DispatchSourceTimer 객체는 프로토콜을 채택할 필요가 없습니다. 대신에 makeTimerSource(flags:queue:) 함수를 사용하여 프로토콜을 채택하여 객체를 생성할 수 있습니다.

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🗂 DispatchSourceTimer Scheduling the Timer Trigger Conditions

🌍 func schedule(deadline: DispatchTime, repeating: DispatchTimeInterval, leeway: DispatchTimeInterval)

• Schedules a timer with the specified deadline, repeat interval, and leeway values.
• 구체적인 마감시간, 반복 주기 그리고 여유 값을 통하여 타이머를 예약합니다.

🌍 func schedule(deadline: DispatchTime, repeating: Double, leeway: DispatchTimeInterval)

• Schedules a timer with the specified deadline, repeat interval, and leeway values.
• 구체적인 마감시간, 반복 주기 그리고 여유 값을 통하여 타이머를 예약합니다.

🌍 func schedule(wallDeadline: DispatchWallTime, repeating: DispatchTimeInterval, leeway: DispatchTimeInterval)

• Schedules a timer with the specified time, repeat interval, and leeway values.
• 구체적인 시간, 반복 주기 그리고 여유 값을 통하여 타이머를 예약합니다.

🌍 func schedule(wallDeadline: DispatchWallTime, repeating: Double, leeway: DispatchTimeInterval)

• Schedules a timer with the specified time, repeat interval, and leeway values.
• 구체적인 마감시간, 반복 주기 그리고 여유 값을 통하여 타이머를 예약합니다.

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🗂 DispatchSourceTimer Example Source Code

DispatchSourceTimer.swift

0.00MB

📔 DispatchSourceTimer Example Swift Source Code 001

var timer: DispatchSourceTimer?

private func startTimer() {
    let queue = DispatchQueue(label: "com.firm.app.timer", attributes: .concurrent)

    timer?.cancel()        // cancel previous timer if any

    timer = DispatchSource.makeTimerSource(queue: queue)

    timer?.schedule(deadline: .now(), repeating: .seconds(5), leeway: .milliseconds(100))

    // or, in Swift 3:
    //
    // timer?.scheduleRepeating(deadline: .now(), interval: .seconds(5), leeway: .seconds(1))

    timer?.setEventHandler { [weak self] in // `[weak self]` only needed if you reference `self` in this closure and you want to prevent strong reference cycle
        print(Date())
    }

    timer?.resume()
}

private func stopTimer() {
    timer?.cancel()
    timer = nil
}

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📔 DispatchSourceTimer Example Swift Source Code 002

var timer: DispatchSourceTimer?  // note, unlike `Timer`, we have to maintain strong reference to GCD timer sources

func createTimer() {
    timer = DispatchSource.makeTimerSource(queue: .main)
    timer?.schedule(deadline: .now(), repeating: 1.0)

    timer?.setEventHandler { [weak self] in      // assuming you're referencing `self` in here, use `weak` to avoid strong reference cycles
        // do something
    }

    // note, timer is not yet started; you have to call `timer?.resume()`
}

func startTimer() {
    timer?.resume()
}

func pauseTiemr() {
    timer?.suspend()
}

func stopTimer() {
    timer?.cancel()
    timer = nil
}

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🚀 REFERENCE

DispatchSourceTimer - Dispatch | Apple Developer Documentation

DispatchSourceTimer and Swift 3.0

A Background Repeating Timer in Swift

Stop and restart a timer