SwiftTimerQueue

README.md

@@ -80,6 +80,16 @@ timer = SwiftCountDownTimer(interval: .fromSeconds(0.1), times: 10) { timer , le
 timer.start()
 ~~~
 
+### timer queue
+
+~~~swift
+timer = SwiftTimerQueue.init(interval: . seconds(1))
+for i in 0..<50{
+    timer.addQueue {
+        label.text = "\(i)"
+    }
+}
+~~~
 
 
 ## Installation

Sources/SwiftTimer.swift

@@ -190,3 +190,56 @@ public extension DispatchTimeInterval {
         return .milliseconds(Int(seconds * 1000))
     }
 }
+
+
+public class SwiftTimerQueue {
+
+    private let internalTimer: SwiftTimer
+    private var workQueue:[DispatchWorkItem]
+
+
+    ///The Handler will be called after interval you specified
+    ///Calling again in the interval cancels the previous call
+    public init(interval: DispatchTimeInterval, queue: DispatchQueue = .main) {
+        self.workQueue = []
+        self.internalTimer = SwiftTimer.init(interval: interval, repeats: true, queue: queue) { _ in
+        }
+        self.internalTimer.rescheduleHandler {[weak self] swiftTimer in
+            if let strongSelf = self,let command = strongSelf.workQueue.first,!command.isCancelled {
+                queue.async(execute: command)
+            }
+        }
+    }
+
+    func addQueue(_ handler: @escaping () -> Void ) {
+        let item = DispatchWorkItem {[weak self] in
+            guard let weak = self else{
+                return
+            }
+            if weak.workQueue.count > 0{
+                weak.workQueue.removeFirst()
+            }
+            handler();
+        };
+        workQueue.append(item)
+    }
+
+    func clean() {
+        for item in workQueue{
+            item.cancel()
+        }
+        workQueue = []
+    }
+
+    func flowCount()->Int {
+        return workQueue.count
+    }
+
+    public func start() {
+        self.internalTimer.start()
+    }
+
+    public func suspend() {
+        self.internalTimer.suspend()
+    }
+}

SwiftTimer iOSTests/SwiftTimer_iOSTests.swift

@@ -165,4 +165,25 @@ class SwiftTimer_iOSTests: XCTestCase {
         self.waitForExpectations(timeout: 1.01, handler: nil)
 
     }
+
+    func testTimerQueue() {
+
+        let expectation = self.expectation(description: "test timer queue")
+
+        let label = UILabel()
+
+        let timer = SwiftTimerQueue.init(interval: .seconds(1))
+        for i in 0..<50{
+            timer.addQueue {
+                label.text = "\(i)"
+            }
+        }
+        timer.addQueue {
+            expectation.fulfill()
+        }
+        timer.start()
+
+        self.waitForExpectations(timeout: 51, handler: nil)
+
+    }
 }