add intervael

MediaSlideshow/Source/MediaSlideshow.swift

@@ -28,7 +28,7 @@ public protocol MediaSlideshowDelegate: class {
     @objc optional func mediaSlideshowDidEndDecelerating(_ mediaSlideshow: MediaSlideshow)
 }
 
-/** 
+/**
     Used to represent position of the Page Control
     - hidden: Page Control is hidden
     - insideScrollView: Page Control is inside image slideshow
@@ -73,6 +73,14 @@ open class MediaSlideshow: UIView {
             reloadScrollView()
         }
     }
+
+    open var circular = true {
+        didSet {
+            if sources.count > 0 {
+                setMediaSources(sources)
+            }
+        }
+    }
 
     open var pageIndicator: PageIndicatorView? {
         didSet {
@@ -177,6 +185,14 @@ open class MediaSlideshow: UIView {
         }
     }
 
+    /// Image change interval, zero stops the auto-scrolling
+    open var slideshowInterval = 0.0 {
+        didSet {
+            slideshowTimer?.invalidate()
+            slideshowTimer = nil
+            setTimerIfNeeded()
+        }
+    }
     /// Image preload configuration, can be sed to .fixed to enable lazy load or .all
     open var preload = ImagePreload.all
 
@@ -189,6 +205,8 @@ open class MediaSlideshow: UIView {
         }
     }
 
+    fileprivate var slideshowTimer: Timer?
+    fileprivate var scrollViewImages = [MediaSource]()
     fileprivate var isAnimating: Bool = false
 
     /// Transitioning delegate to manage the transition to full screen controller
@@ -242,9 +260,15 @@ open class MediaSlideshow: UIView {
             pageIndicator = UIPageControl()
         }
 
+        setTimerIfNeeded()
         layoutScrollView()
     }
 
+    open override func removeFromSuperview() {
+        super.removeFromSuperview()
+        pauseTimer()
+    }
+
     open override func layoutSubviews() {
         super.layoutSubviews()
 
@@ -331,10 +355,32 @@ open class MediaSlideshow: UIView {
      */
     public func setMediaSources(_ sources: [MediaSource]) {
         self.sources = sources
+
         pageIndicator?.numberOfPages = sources.count
+
+        // in circular mode we add dummy first and last image to enable smooth scrolling
+        if circular && sources.count > 1 {
+            var scImages = [MediaSource]()
+
+            if let last = sources.last {
+                scImages.append(last)
+            }
+            scImages += sources
+            if let first = sources.first {
+                scImages.append(first)
+            }
+
+            scrollViewImages = scImages
+        } else {
+            scrollViewImages = sources
+        }
+
+
         reloadScrollView()
         layoutScrollView()
         layoutPageControl()
+        setTimerIfNeeded()
+
     }
 
     // MARK: paging methods
@@ -345,7 +391,13 @@ open class MediaSlideshow: UIView {
      - parameter animated: true if animate the change
      */
     open func setCurrentPage(_ newPage: Int, animated: Bool) {
-        setScrollViewPage(newPage, animated: animated)
+        var pageOffset = newPage
+        if circular && (scrollViewImages.count > 1) {
+            pageOffset += 1
+        }
+
+        setScrollViewPage(pageOffset, animated: animated)
+
     }
 
     /**
@@ -362,6 +414,24 @@ open class MediaSlideshow: UIView {
             }
         }
     }
+
+    fileprivate func setTimerIfNeeded() {
+        if slideshowInterval > 0 && scrollViewImages.count > 1 && slideshowTimer == nil {
+            slideshowTimer = Timer.scheduledTimer(timeInterval: slideshowInterval, target: self, selector: #selector(MediaSlideshow.slideshowTick(_:)), userInfo: nil, repeats: true)
+        }
+    }
+
+    func slideshowTick(_ timer: Timer) {
+        let page = scrollView.frame.size.width > 0 ? Int(scrollView.contentOffset.x / scrollView.frame.size.width) : 0
+        var nextPage = page + 1
+
+        if !circular && page == scrollViewImages.count - 1 {
+            nextPage = 0
+        }
+
+        setScrollViewPage(nextPage, animated: true)
+    }
+
 
     fileprivate func setCurrentPageForScrollViewPage(_ page: Int) {
         if scrollViewPage != page {
@@ -381,32 +451,86 @@ open class MediaSlideshow: UIView {
     }
 
     fileprivate func currentPageForScrollViewPage(_ page: Int) -> Int {
-        page
+        if circular {
+            if page == 0 {
+                // first page contains the last image
+                return Int(sources.count) - 1
+            } else if page == scrollViewImages.count - 1 {
+                // last page contains the first image
+                return 0
+            } else {
+                return page - 1
+            }
+        } else {
+            return page
+        }
+    }
+
+    fileprivate func restartTimer() {
+        if slideshowTimer?.isValid != nil {
+            slideshowTimer?.invalidate()
+            slideshowTimer = nil
+        }
+
+        setTimerIfNeeded()
+    }
+
+
+    /// Stops slideshow timer
+    open func pauseTimer() {
+        slideshowTimer?.invalidate()
+        slideshowTimer = nil
+    }
+
+    /// Restarts slideshow timer
+    open func unpauseTimer() {
+        setTimerIfNeeded()
+    }
+
+    @available(*, deprecated, message: "use pauseTimer instead")
+    open func pauseTimerIfNeeded() {
+        pauseTimer()
+    }
+
+    @available(*, deprecated, message: "use unpauseTimer instead")
+    open func unpauseTimerIfNeeded() {
+        unpauseTimer()
     }
 
     /**
      Change the page to the next one
      - Parameter animated: true if animate the change
      */
     open func nextPage(animated: Bool) {
+        if !circular && currentPage == sources.count - 1 {
+            return
+        }
         if isAnimating {
             return
         }
+
         setCurrentPage(currentPage + 1, animated: animated)
+        restartTimer()
     }
 
     /**
      Change the page to the previous one
      - Parameter animated: true if animate the change
      */
     open func previousPage(animated: Bool) {
+        if !circular && currentPage == 0 {
+            return
+        }
         if isAnimating {
             return
         }
-        let newPage = scrollViewPage > 0 ? scrollViewPage - 1 : sources.count - 3
+
+        let newPage = scrollViewPage > 0 ? scrollViewPage - 1 : scrollViewImages.count - 3
         setScrollViewPage(newPage, animated: animated)
+        restartTimer()
     }
 
+
     @objc private func pageControlValueChanged() {
         if let currentPage = pageIndicator?.page {
             setCurrentPage(currentPage, animated: true)
@@ -417,6 +541,7 @@ open class MediaSlideshow: UIView {
 extension MediaSlideshow: UIScrollViewDelegate {
 
     open func scrollViewWillBeginDragging(_ scrollView: UIScrollView) {
+        restartTimer()
         willBeginDragging?()
         delegate?.mediaSlideshowWillBeginDragging?(self)
     }
@@ -426,15 +551,32 @@ extension MediaSlideshow: UIScrollViewDelegate {
         didEndDecelerating?()
         delegate?.mediaSlideshowDidEndDecelerating?(self)
     }
-
+//
+//    open func scrollViewDidScroll(_ scrollView: UIScrollView) {
+//        // Updates the page indicator as the user scrolls (#204). Not called when not dragging to prevent flickers
+//        // when interacting with PageControl directly (#376).
+//        if scrollView.isDragging {
+//            pageIndicator?.page = currentPageForScrollViewPage(primaryVisiblePage)
+//        }
+//    }
     open func scrollViewDidScroll(_ scrollView: UIScrollView) {
+        if circular && (scrollViewImages.count > 1) {
+            let regularContentOffset = scrollView.frame.size.width * CGFloat(sources.count)
+
+            if scrollView.contentOffset.x >= scrollView.frame.size.width * CGFloat(sources.count + 1) {
+                scrollView.contentOffset = CGPoint(x: scrollView.contentOffset.x - regularContentOffset, y: 0)
+            } else if scrollView.contentOffset.x <= 0 {
+                scrollView.contentOffset = CGPoint(x: scrollView.contentOffset.x + regularContentOffset, y: 0)
+            }
+        }
+
         // Updates the page indicator as the user scrolls (#204). Not called when not dragging to prevent flickers
         // when interacting with PageControl directly (#376).
         if scrollView.isDragging {
             pageIndicator?.page = currentPageForScrollViewPage(primaryVisiblePage)
         }
     }
-
+        
     public func scrollViewDidEndScrollingAnimation(_ scrollView: UIScrollView) {
         isAnimating = false
     }