Merge pull request #97 from onevcat/fix/reset-image-from-stop

Reset frame content when start the image view again from stop
onevcat · Mar 8, 2020 · df003ea · df003ea
2 parents fd53084 + cffd39b
commit df003ea
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Showing 2 changed files with 17 additions and 12 deletions.
diff --git a/APNGKit/APNGImage.swift b/APNGKit/APNGImage.swift
@@ -101,7 +101,7 @@ open class APNGImage: NSObject { // For ObjC compatibility
         }
     }
 
-    // Strong refrence to another APNG to hold data if this image object is retrieved from cache
+    // Strong reference to another APNG to hold data if this image object is retrieved from cache
     // The frames data will not be changed once a frame is setup.
     // So we could share the bytes in it between two "same" APNG image objects.
     fileprivate let dataOwner: APNGImage?
@@ -129,7 +129,7 @@ open class APNGImage: NSObject { // For ObjC compatibility
         self.disassembler = nil
     }
 
-    // Init from a disaabler. This happens when loading progressivly.
+    // Init from a disassembler. This happens when loading progressively.
     convenience init(disassembler: Disassembler, scale: CGFloat, meta: APNGMeta) {
         self.init(scale: scale, meta: meta)
         self.disassembler = disassembler

diff --git a/APNGKit/APNGImageView.swift b/APNGKit/APNGImageView.swift
@@ -62,11 +62,8 @@ open class APNGImageView: APNGView {
             }
 
             image.reset()
+            setCurrentFrame()
 
-            let frame = image.next(currentIndex: currentFrameIndex)
-            currentFrameDuration = frame.duration
-            updateContents(frame.image)
-
             if animating {
                 startAnimating()
             }
@@ -219,7 +216,11 @@ open class APNGImageView: APNGView {
         if isAnimating {
             return
         }
-
+
+        // Reset display content. It is necessary when restart the image view from a
+        // previous stop. https://github.com/onevcat/APNGKit/issues/96
+        setCurrentFrame()
+
         isAnimating = true
         timer = GCDTimer(intervalInSecs: 0.016)
         timer!.Event = { [weak self] in
@@ -330,12 +331,16 @@ open class APNGImageView: APNGView {
             }
 
             currentPassedDuration = currentPassedDuration - currentFrameDuration
-
-            let frame = image.next(currentIndex: currentFrameIndex)
-            currentFrameDuration = frame.duration
-            updateContents(frame.image)
+
+            setCurrentFrame()
         }
-
+    }
+
+    private func setCurrentFrame() {
+        guard let image = image else { return }
+        let frame = image.next(currentIndex: currentFrameIndex)
+        currentFrameDuration = frame.duration
+        updateContents(frame.image)
     }
 
     func updateContents(_ image: CocoaImage?) {