UIImage created with animatedImageWithImages have bugs? - ios

Question

Recently I found sometimes my gif image not shown. So I write a test code for it:
import UIKit
import ImageIO
extension UIImage {
static func gifImageArray(data: NSData) -> [UIImage] {
let source = CGImageSourceCreateWithData(data, nil)!
let count = CGImageSourceGetCount(source)
if count <= 1 {
return [UIImage(data: data)!]
} else {
var images = [UIImage](); images.reserveCapacity(count)
for i in 0..<count {
let image = CGImageSourceCreateImageAtIndex(source, i, nil)!
images.append( UIImage(CGImage: image) )
}
return images;
}
}
static func gifImage(data: NSData) -> UIImage? {
let gif = gifImageArray(data)
if gif.count <= 1 {
return gif[0]
} else {
return UIImage.animatedImageWithImages(gif, duration: NSTimeInterval(gif.count) * 0.1)
}
}
}
class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
let _gifData : NSData = NSData(contentsOfURL: NSURL(string: "https://upload.wikimedia.org/wikipedia/commons/d/d3/Newtons_cradle_animation_book_2.gif")!)!
lazy var _gifImageArray : [UIImage] = UIImage.gifImageArray(self._gifData)
lazy var _gifImage : UIImage = UIImage.gifImage(self._gifData)!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
let table = UITableView(frame: self.view.bounds, style: .Plain)
table.dataSource = self
table.delegate = self
self.view.addSubview(table)
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 1000;
}
func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return 1;
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let identifier = "cell"
var cell : UITableViewCell! = tableView.dequeueReusableCellWithIdentifier(identifier);
if cell == nil {
cell = UITableViewCell(style: .Default, reuseIdentifier: identifier)
}
if let imageView = cell.imageView {
/** 1. use the same UIImage object created by animatedImageWithImages
the image disappear when reuse, and when touching cell, it reappear. */
imageView.image = self._gifImage
/** 2. create different UIImage by using same image array. this still not work */
// imageView.image = UIImage.animatedImageWithImages(self._gifImageArray, duration: NSTimeInterval(self._gifImageArray.count) * 0.1)
/** 3. create different UIImage from data, this seems work
but use a lot of memories. and seems it has performance issue. */
// imageView.image = UIImage.gifImage(self._gifData)
/** 4. use same image array as imageView's animationImages.
this kind works, but have different api than just set image.
and when click on cell, the animation stops. */
// imageView.image = self._gifImageArray[0]
// imageView.animationImages = self._gifImageArray
// imageView.startAnimating()
}
return cell
}
}
Notice in the cellForRowAtIndexPath: method, I tried different way to set imageView.
when I po object in lldb, I notice the animated imageView have a CAKeyframeAnimation. does this makes a tip?
How can I make the gif shown perfectly? Any suggestion would be helpful.
Here is a preview: after scroll, gif disappear, and reappear when touch

Answer 1

After I tried many times, I have finally figured out that I need to change:
imageView.image = self._gifImage
to:
imageView.image = nil // this is the magical!
imageView.image = self._gifImage
just set image to nil before set to new image, and the animation work!! It's just like a magical!
This is definitely apple's bug.

Answer 2

try by replacing imageView with myImageview or other name because cell have default imageView property so when you call cell.imageView then it returns cell's default imageview i think. so change your cell's imageview's variable name. hope this will help :)

Answer 3

maybe image class need SDAnimatedImage instead of UIImage