Made calling SwiftGif Easier

README.md

@@ -8,11 +8,10 @@ A small `UIImage` extension with gif support.
 Import the `Gif.swift` in your project and do the following:
 ```swift
 // jeremy.gif
-var url = NSBundle.mainBundle().URLForResource("jeremy", withExtension: "gif")
-var imageData = NSData(contentsOfURL: url)
-
 // Returns an animated UIImage
-UIImage.animatedImageWithData(imageData)
+let jeremyGif = UIImage.gifWithName("jeremy")
+// Use the UIImage in your UIImageView
+let imageView = UIImageView(image: jeremyGif)
 ```
 
 ## How does it work?

SwiftGifCommon/UIImage+Gif.swift

@@ -10,17 +10,30 @@ import UIKit
 import ImageIO
 
 extension UIImage {
-
-    public class func animatedImageWithData(data: NSData) -> UIImage? {
-        guard let source = CGImageSourceCreateWithData(data, nil) else { return nil }
-
+
+    public class func gifWithData(data: NSData) -> UIImage? {
+        guard let source = CGImageSourceCreateWithData(data, nil) else {
+            print("SwiftGif: Source for the image does not exist")
+            return nil
+        }
         return UIImage.animatedImageWithSource(source)
     }
-
-    class func delayForImageAtIndex(index: Int, source: CGImageSource!)
-        -> Double {
+
+    public class func gifWithName(name: String) -> UIImage? {
+        guard let bundleURL = NSBundle.mainBundle().URLForResource(name, withExtension: "gif") else {
+            print("SwiftGif: This image named \"\(name)\" does not exist")
+            return nil
+        }
+        guard let imageData = NSData(contentsOfURL: bundleURL) else {
+            print("SwiftGif: Cannot turn image named \"\(name)\" into NSData")
+            return nil
+        }
+        return gifWithData(imageData)
+    }
+
+    class func delayForImageAtIndex(index: Int, source: CGImageSource!) -> Double {
         var delay = 0.1
-
+        
         // Get dictionaries
         let cfProperties = CGImageSourceCopyPropertiesAtIndex(source, index, nil)
         let gifProperties: CFDictionaryRef = unsafeBitCast(
@@ -37,17 +50,16 @@ extension UIImage {
             delayObject = unsafeBitCast(CFDictionaryGetValue(gifProperties,
                 unsafeAddressOf(kCGImagePropertyGIFDelayTime)), AnyObject.self)
         }
-
+        
         delay = delayObject as! Double
-
+        
         if delay < 0.1 {
             delay = 0.1 // Make sure they're not too fast
         }
-
-
+
         return delay
     }
-
+    
     class func gcdForPair(var a: Int?, var _ b: Int?) -> Int {
         // Check if one of them is nil
         if b == nil || a == nil {
@@ -59,19 +71,19 @@ extension UIImage {
                 return 0
             }
         }
-
+        
         // Swap for modulo
         if a < b {
             let c = a
             a = b
             b = c
         }
-
+        
         // Get greatest common divisor
         var rest: Int
         while true {
             rest = a! % b!
-
+            
             if rest == 0 {
                 return b! // Found it
             } else {
@@ -80,70 +92,70 @@ extension UIImage {
             }
         }
     }
-
+    
     class func gcdForArray(array: Array<Int>) -> Int {
         if array.isEmpty {
             return 1
         }
-
+        
         var gcd = array[0]
-
+        
         for val in array {
             gcd = UIImage.gcdForPair(val, gcd)
         }
-
+        
         return gcd
     }
-
-    public class func animatedImageWithSource(source: CGImageSource) -> UIImage? {
+    
+    class func animatedImageWithSource(source: CGImageSource) -> UIImage? {
         let count = CGImageSourceGetCount(source)
         var images = [CGImageRef]()
         var delays = [Int]()
-
+        
         // Fill arrays
         for i in 0..<count {
             // Add image
             if let image = CGImageSourceCreateImageAtIndex(source, i, nil) {
                 images.append(image)
             }
-
+            
             // At it's delay in cs
             let delaySeconds = UIImage.delayForImageAtIndex(Int(i),
                 source: source)
             delays.append(Int(delaySeconds * 1000.0)) // Seconds to ms
         }
-
+        
         // Calculate full duration
         let duration: Int = {
             var sum = 0
-
+            
             for val: Int in delays {
                 sum += val
             }
-
+            
             return sum
             }()
-
+        
         // Get frames
         let gcd = gcdForArray(delays)
         var frames = [UIImage]()
-
+        
         var frame: UIImage
         var frameCount: Int
         for i in 0..<count {
             frame = UIImage(CGImage: images[Int(i)])
             frameCount = Int(delays[Int(i)] / gcd)
-
+            
             for _ in 0..<frameCount {
                 frames.append(frame)
             }
         }
-
+        
         // Heyhey
         let animation = UIImage.animatedImageWithImages(frames,
             duration: Double(duration) / 1000.0)
-
+        
         return animation
     }
-
+    
 }

SwiftGifDemo/RootViewController.swift

@@ -22,22 +22,19 @@ class RootViewController: UIViewController {
     override func viewDidLoad() {
         super.viewDidLoad()
 
-        var imageData = NSData(contentsOfURL: NSBundle.mainBundle()
-            .URLForResource("jeremy", withExtension: "gif")!)
-        let jeremy = UIImage.animatedImageWithData(imageData!)
-        var imageView = UIImageView(image: jeremy)
+        let jeremyGif = UIImage.gifWithName("jeremy")
+        let imageView = UIImageView(image: jeremyGif)
         imageView.frame = CGRect(x: 0.0, y: 20.0, width: 350.0, height: 202.0)
 
         view.addSubview(imageView)
 
 
-        imageData = NSData(contentsOfURL: NSBundle.mainBundle()
-            .URLForResource("adventure-time", withExtension: "gif")!)
-        let advTime = UIImage.animatedImageWithData(imageData!)
-        imageView = UIImageView(image: advTime)
-        imageView.frame = CGRect(x: 0.0, y: 222.0, width: 350.0, height: 202.0)
+        let imageData = NSData(contentsOfURL: NSBundle.mainBundle().URLForResource("adventure-time", withExtension: "gif")!)
+        let advTimeGif = UIImage.gifWithData(imageData!)
+        let imageView2 = UIImageView(image: advTimeGif)
+        imageView2.frame = CGRect(x: 0.0, y: 222.0, width: 350.0, height: 202.0)
 
-        view.addSubview(imageView)
+        view.addSubview(imageView2)
     }
 
     override func didReceiveMemoryWarning() {