iOS开发之展示gif图像
这个也是这段时间解决的问题，展示gif图像，在这里给大家也分享一下
1.使用SDWebImage
SDWebImage比较占内存，但是问题不大
导入头文件
#import "UIImage+GIF.h"
设置gif图
self.imageView.image = [UIImage sd_animatedGIFNamed:@"test"];
也可以通过NSData导入
+ (UIImage *)sd_animatedGIFWithData:(NSData *)data
原理：
1.将gif图的每一帧导出为一个UIImage,并且算出每一帧的播放时间,将导出的image放入images数组中
2.使用+ animatedImageWithImages: duration: 方法创建image,参数为第一步的images数组和播放总时长
3.设置UIImageView的image时用sd_animatedGIFNamed:方法即可展示gif
2.使用FLAnimatedImage
导入头文件
#import "FLAnimatedImage.h"
设置gif图
NSString *path = [[NSBundle mainBundle] pathForResource:@"test" ofType:@"gif"];
NSData *data = [NSData dataWithContentsOfFile:path];
FLAnimatedImage *image = [FLAnimatedImage animatedImageWithGIFData:data];
self.imageView.animatedImage = image;
特点:加载速度略长,但是性能更优，播放的gif动态图更加流畅。
.m文件
//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<UIImage *> * imageArray, NSArray<NSNumber *>*timeArray,CGFloat totalTime, NSArray<NSNumber *>* widths,NSArray<NSNumber *>* 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<count; 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<UIImage *> *imageArray, NSArray<NSNumber *> *timeArray, CGFloat totalTime, NSArray<NSNumber *> *widths, NSArray<NSNumber *> *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<imageArray.count; 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"];
}];
}
方法使用：
UIImageView * imageView = [[UIImageView alloc]initWithFrame:CGRectMake(f_Device_w*i, 0, f_Device_w, f_Device_h)];
NSURL * url = [NSURL URLWithString:[NSString stringWithFormat:@"http://ycbook.11space.cn%@",imgArray[i]]];
[imageView yh_setImage:url];
[self.view addSubview:imageView];
展示gif动图的UIImageView类别源码：https://github.com/hbblzjy/UIImageViewTool
有问题请留言。。。