1.系统UIImageView 多张图片组成动画
/** * UIImageView 动画 * Memory-23M */
-(void)gifPlay1 {
// NSArray *array=@[@"image0.png",@"image1.png",@"image2.png"];
// UIImageView *imgview= [UIImageView imageViewAnimation:CGRectMake(50,80, 550/2, 200) imageNames:array duration:1];
UIImageView* animatedImageView = [[UIImageView alloc] initWithFrame:CGRectMake(50,80, 550/2, 200)]; animatedImageView.animationImages =@[[UIImage imageNamed:@"image0"], [UIImage imageNamed:@"image1"], [UIImage imageNamed:@"image2"] ];
animatedImageView.animationDuration = 1.0f;
animatedImageView.animationRepeatCount = 0;
[self.view addSubview: animatedImageView];
[animatedImageView startAnimating];
}
2.利用第三方库
1）IImageView-PlayGIF YFGIFImageView
/** * UIImageView-PlayGIF 是 UIImageView 子类，用来显示 GIF。UIIMageView-PlayGIF 性能高，而且占用的内存很低。
* https://github.com/yfme/UIImageView-PlayGIF * Memory-21.9M *
#import "YFGIFImageView.h"
*/
-(void)gifPlay2 {
NSString *gifPath=[[NSBundle mainBundle] pathForResource:@"test" ofType:@"gif"];
YFGIFImageView *gifview=[[YFGIFImageView alloc]init];
gifview.backgroundColor=[UIColor clearColor];
gifview.gifPath=gifPath;
gifview.frame=CGRectMake(50, 100,550/2, 200);
[self.view addSubview:gifview];
[gifview startGIF];
}
2）SCGIFImageView
/** * 摘要: SCGIFImageView是一个开源的GIF图片动画显示控件，通过将GIF的每一帧都取出来生成UIImage对象存放在一个数组中，然后使用NSTimer进行动画轮转。
* https://github.com/shichangone/SCGifExample * Memory-22.5M *
#import "SCGIFImageView.h"
*/
-(void)gifPlay3 {
NSString* filePath = [[NSBundle mainBundle] pathForResource:@"test.gif" ofType:nil];
NSData* imageData = [NSData dataWithContentsOfFile:filePath];
SCGIFImageView* gifImageView = [[SCGIFImageView alloc]init];
[gifImageView setData:imageData];
gifImageView.frame = CGRectMake(50,100, gifImageView.image.size.width, gifImageView.image.size.height); [self.view addSubview:gifImageView];
}
3）YLGIFImage
/** * YLGIFImage 是异步 GIF 图像解码器和图像查看器，支持播放 GIF 图像，而且使用很少的内存。
* https://github.com/liyong03/YLGIFImage * Memory-22.7M
* #import "YLImageView.h"
* #import "YLGIFImage.h"
*/
-(void)gifPlay5 {
YLImageView* imageView = [[YLImageView alloc] initWithFrame:CGRectMake(0, 160, 320, 240)];
[self.view addSubview:imageView];
imageView.image = [YLGIFImage imageNamed:@"test.gif"];
}
4）SDWebImageView里的UIImage+GIF
提供接口：
+ (UIImage *)sd_animatedGIFNamed:(NSString *)name;
+ (UIImage *)sd_animatedGIFWithData:(NSData *)data;
- (UIImage *)sd_animatedImageByScalingAndCroppingToSize:(CGSize)size;
/** * 利用SDWebImageView 库播放gif * Memory-22.6M *
#import "UIImage+GIF.h"
*/
-(void)gifPlay6 {
UIImage *image=[UIImage sd_animatedGIFNamed:@"test"];
UIImageView *gifview=[[UIImageView alloc]initWithFrame:CGRectMake(50,80,image.size.width, image.size.height)]; gifview.backgroundColor=[UIColor orangeColor];
gifview.image=image;
[self.view addSubview:gifview];
}
5）为MBProgressHUD 添加加载动画
/** * MBProgressHUD 添加加载动画 * Memory-23.8M *
#import "UIImage+GIF.h"
* #import "MBProgressHUD.h"
*/
-(void)gifPlay6 {
UIImage *image=[UIImage sd_animatedGIFNamed:@"test"];
UIImageView *gifview=[[UIImageView alloc]initWithFrame:CGRectMake(0,0,image.size.width/2, image.size.height/2)];
gifview.image=image;
MBProgressHUD *hud = [MBProgressHUD showHUDAddedTo:self.view animated:YES];
hud.color=[UIColor grayColor];//默认颜色太深了
hud.mode = MBProgressHUDModeCustomView;
hud.labelText = @"加载中...";
hud.customView=gifview;
}
3.为原生的UIImageView添加类别来支持gif动态图的播放
gif动态图文件中包含了一组图片及其信息，信息主要记录着每一帧图片播放的时间，我们如果获取到了gif文件中所有的图片同时又获取到每一帧图片播放的时间，就可以为UIImageView添加核心动画的方法来让其播放gif的内容了。
首先解析gif文件中的数据，代码如下：
//要引入ImageIO库
#import
//解析gif文件数据的方法 block中会将解析的数据传递出来
-(void)getGifImageWithUrk:(NSURL *)url
returnData:(void(^)(NSArray * imageArray,
NSArray*timeArray,
CGFloat totalTime,
NSArray* widths,
NSArray* heights))dataBlock{
//通过文件的url来将gif文件读取为图片数据引用
CGImageSourceRef source = CGImageSourceCreateWithURL((CFURLRef)url, NULL);
//获取gif文件中图片的个数
size_t count = CGImageSourceGetCount(source);
//定义一个变量记录gif播放一轮的时间
float allTime=0;
//存放所有图片
NSMutableArray * imageArray = [[NSMutableArray alloc]init];
//存放每一帧播放的时间
NSMutableArray * timeArray = [[NSMutableArray alloc]init];
//存放每张图片的宽度 （一般在一个gif文件中，所有图片尺寸都会一样）
NSMutableArray * widthArray = [[NSMutableArray alloc]init];
//存放每张图片的高度
NSMutableArray * heightArray = [[NSMutableArray alloc]init];
//遍历
for (size_t i=0; i
CGImageRef image = CGImageSourceCreateImageAtIndex(source, i, NULL);
[imageArray addObject:(__bridge UIImage *)(image)];
CGImageRelease(image);
//获取图片信息
NSDictionary * info = (__bridge NSDictionary*)CGImageSourceCopyPropertiesAtIndex(source, i, NULL);
CGFloat width = [[info objectForKey:(__bridge NSString *)kCGImagePropertyPixelWidth] floatValue];
CGFloat height = [[info objectForKey:(__bridge NSString *)kCGImagePropertyPixelHeight] floatValue];
[widthArray addObject:[NSNumber numberWithFloat:width]];
[heightArray addObject:[NSNumber numberWithFloat:height]];
NSDictionary * timeDic = [info objectForKey:(__bridge NSString *)kCGImagePropertyGIFDictionary];
CGFloat time = [[timeDic objectForKey:(__bridge NSString *)kCGImagePropertyGIFDelayTime]floatValue];
allTime+=time;
[timeArray addObject:[NSNumber numberWithFloat:time]];
}
dataBlock(imageArray,timeArray,allTime,widthArray,heightArray);
}
为UIImageView添加一个设置gif图内容的方法：
-(void)yh_setImage:(NSURL *)imageUrl{
__weak id __self = self;
[self getGifImageWithUrk:imageUrl returnData:^(NSArray *imageArray, NSArray *timeArray, CGFloat totalTime, NSArray *widths, NSArray *heights) {
//添加帧动画
CAKeyframeAnimation *animation = [CAKeyframeAnimation animationWithKeyPath:@"contents"];
NSMutableArray * times = [[NSMutableArray alloc]init];
float currentTime = 0;
//设置每一帧的时间占比
for (int i=0; i
[times addObject:[NSNumber numberWithFloat:currentTime/totalTime]];
currentTime+=[timeArray[i] floatValue];
}
[animation setKeyTimes:times];
[animation setValues:imageArray];
[animation setTimingFunction:[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear]];
//设置循环
animation.repeatCount= MAXFLOAT;
//设置播放总时长
animation.duration = totalTime;
//Layer层添加
[[(UIImageView *)__self layer]addAnimation:animation forKey:@"gifAnimation"];
}];
}
使用代码示例如下：
UIImageView * imageView = [[UIImageView alloc]initWithFrame:CGRectMake(0,0 , 320, 200)];
NSURL * url = [[NSURL alloc]initFileURLWithPath:[[NSBundle mainBundle] pathForResource:imageName ofType:nil]];
[imageView yh_setImage:url];
[self.view addSubview:imageView];
三、使用UIWebView来加载gif动态图数据
iOS中的UIWebView功能十分强大，可以通过UIWebView为载体，来展示gif图。并且这种方法也十分简单，代码如下：
//读取gif数据
NSData *gifData = [NSData dataWithContentsOfURL:imageUrl];
UIWebView *webView = [[UIWebView alloc] initWithFrame:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
//取消回弹效果
webView.scrollView.bounces=NO;
webView.backgroundColor = [UIColor clearColor];
//设置缩放模式
webView.scalesPageToFit = YES;
//用webView加载数据
[webView loadData:gifData MIMEType:@"image/gif" textEncodingName:nil baseURL:nil];
＊上面两种加载gif动态图方式的优劣
经过测试，从加载速度上来说，通过UIImageView类别加载的方式更加快速，UIWebView的方式加载时间会稍长，但是从性能上来比较，WebView的方式性能更优，播放的gif动态图更加流畅。在开发中，可以根据需求，适当选择，例如虽然WebView加载的方式性能更好，但是在许多情况下，原生的UIImageView能够更加自由的让开发者进行扩展。
