一、简单介绍
gif动画是iOS开发中很常用的一个功能，有的是为了显示加载视频的过程，更多的是为了显示一个结果状态（动画更直观）。
那么如何执行gif动画，方法有很多。（这里只写一下方法三，前两种之前都用过）
方法一使用UIWebView来显示；
方法二使用UIImageView的帧动画显示；
方法三使用SDWebImage这个三方框架来显示。
二、简单使用
1、显示gif动画（三方框架SDWebImage的UIImage+GIF分类）
#import "UIImage+GIF.h"
#import "SDWebImageGIFCoder.h"
#import "NSImage+WebCache.h" @implementation UIImage (GIF) + (UIImage *)sd_animatedGIFWithData:(NSData *)data {
if (!data) {
return nil;
}
return [[SDWebImageGIFCoder sharedCoder] decodedImageWithData:data];
} - (BOOL)isGIF {
return (self.images != nil);
} @end
//使用
NSData *gifData = [NSData dataWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"live_sign" ofType:@"gif"]];
UIImage *signSuccessGifImg = [UIImage sd_animatedGIFWithData:gifData];
self.imageView.image = signSuccessGifImg;
2、获取gif动画时长
//获取gif图片的总时长
- (NSTimeInterval)durationForGifData:(NSData *)data{ //将GIF图片转换成对应的图片源
CGImageSourceRef gifSource = CGImageSourceCreateWithData((__bridge CFDataRef)data, NULL); //获取其中图片源个数，即由多少帧图片组成
size_t frameCout = CGImageSourceGetCount(gifSource); //定义数组存储拆分出来的图片
NSMutableArray* frames = [[NSMutableArray alloc] init];
NSTimeInterval totalDuration = ;
for (size_t i=; i<frameCout; i++) { //从GIF图片中取出源图片
CGImageRef imageRef = CGImageSourceCreateImageAtIndex(gifSource, i, NULL); //将图片源转换成UIimageView能使用的图片源
UIImage* imageName = [UIImage imageWithCGImage:imageRef]; //将图片加入数组中
[frames addObject:imageName];
NSTimeInterval duration = [self gifImageDeleyTime:gifSource index:i];
totalDuration += duration;
CGImageRelease(imageRef);
} //获取循环次数
NSInteger loopCount;//循环次数
CFDictionaryRef properties = CGImageSourceCopyProperties(gifSource, NULL);
if (properties) {
CFDictionaryRef gif = CFDictionaryGetValue(properties, kCGImagePropertyGIFDictionary);
if (gif) {
CFTypeRef loop = CFDictionaryGetValue(gif, kCGImagePropertyGIFLoopCount);
if (loop) {
//如果loop == NULL，表示不循环播放，当loopCount == 0时，表示无限循环；
CFNumberGetValue(loop, kCFNumberNSIntegerType, &loopCount);
};
}
}
CFRelease(gifSource);
return totalDuration;
}
//获取GIF图片每帧的时长
- (NSTimeInterval)gifImageDeleyTime:(CGImageSourceRef)imageSource index:(NSInteger)index {
NSTimeInterval duration = ;
CFDictionaryRef imageProperties = CGImageSourceCopyPropertiesAtIndex(imageSource, index, NULL);
if (imageProperties) {
CFDictionaryRef gifProperties;
BOOL result = CFDictionaryGetValueIfPresent(imageProperties, kCGImagePropertyGIFDictionary, (const void **)&gifProperties);
if (result) {
const void *durationValue;
if (CFDictionaryGetValueIfPresent(gifProperties, kCGImagePropertyGIFUnclampedDelayTime, &durationValue)) {
duration = [(__bridge NSNumber *)durationValue doubleValue];
if (duration < ) {
if (CFDictionaryGetValueIfPresent(gifProperties, kCGImagePropertyGIFDelayTime, &durationValue)) {
duration = [(__bridge NSNumber *)durationValue doubleValue];
}
}
}
}
} return duration;
}
3、获取gif动画执行次数
//获取gif图片的循环次数
-(NSInteger)repeatCountForGifData:(NSData *)data{ //将GIF图片转换成对应的图片源
CGImageSourceRef gifSource = CGImageSourceCreateWithData((__bridge CFDataRef)data, NULL); //获取循环次数
NSInteger loopCount = ;//循环次数
CFDictionaryRef properties = CGImageSourceCopyProperties(gifSource, NULL);
if (properties) {
CFDictionaryRef gif = CFDictionaryGetValue(properties, kCGImagePropertyGIFDictionary);
if (gif) {
CFTypeRef loop = CFDictionaryGetValue(gif, kCGImagePropertyGIFLoopCount);
if (loop) {
//如果loop == NULL，表示不循环播放，当loopCount == 0时，表示无限循环；
CFNumberGetValue(loop, kCFNumberNSIntegerType, &loopCount);
};
}
}
CFRelease(gifSource); return loopCount;
}
三、创建分类
#import "UIImageView+GIFProperty.h"
//
// UIImageView+GIFProperty.h
// YuwenParent
//
// Created by 夏远全 on 2019/4/11.
// Copyright © 2019年 xiaoshuang. All rights reserved.
// #import <UIKit/UIKit.h> NS_ASSUME_NONNULL_BEGIN @interface UIImageView (GIFProperty)
-(NSTimeInterval)durationForGifData:(NSData *)data;//获取gif动画总时长
-(NSInteger)repeatCountForGifData:(NSData *)data; //获取gif动画循环总次数 0:表示无限循环
@end NS_ASSUME_NONNULL_END
//
// UIImageView+GIFProperty.m
// YuwenParent
//
// Created by 夏远全 on 2019/4/11.
// Copyright © 2019年 xiaoshuang. All rights reserved.
// #import "UIImageView+GIFProperty.h" @implementation UIImageView (GIFProperty) //获取gif图片的总时长
- (NSTimeInterval)durationForGifData:(NSData *)data{ //将GIF图片转换成对应的图片源
CGImageSourceRef gifSource = CGImageSourceCreateWithData((__bridge CFDataRef)data, NULL); //获取其中图片源个数，即由多少帧图片组成
size_t frameCout = CGImageSourceGetCount(gifSource); //定义数组存储拆分出来的图片
NSMutableArray* frames = [[NSMutableArray alloc] init];
NSTimeInterval totalDuration = ;
for (size_t i=; i<frameCout; i++) { //从GIF图片中取出源图片
CGImageRef imageRef = CGImageSourceCreateImageAtIndex(gifSource, i, NULL); //将图片源转换成UIimageView能使用的图片源
UIImage* imageName = [UIImage imageWithCGImage:imageRef]; //将图片加入数组中
[frames addObject:imageName];
NSTimeInterval duration = [self gifImageDeleyTime:gifSource index:i];
totalDuration += duration;
CGImageRelease(imageRef);
} //获取循环次数
NSInteger loopCount;//循环次数
CFDictionaryRef properties = CGImageSourceCopyProperties(gifSource, NULL);
if (properties) {
CFDictionaryRef gif = CFDictionaryGetValue(properties, kCGImagePropertyGIFDictionary);
if (gif) {
CFTypeRef loop = CFDictionaryGetValue(gif, kCGImagePropertyGIFLoopCount);
if (loop) {
//如果loop == NULL，表示不循环播放，当loopCount == 0时，表示无限循环；
CFNumberGetValue(loop, kCFNumberNSIntegerType, &loopCount);
};
}
}
CFRelease(gifSource);
return totalDuration;
} //获取gif图片的循环次数
-(NSInteger)repeatCountForGifData:(NSData *)data{ //将GIF图片转换成对应的图片源
CGImageSourceRef gifSource = CGImageSourceCreateWithData((__bridge CFDataRef)data, NULL); //获取循环次数
NSInteger loopCount = ;//循环次数
CFDictionaryRef properties = CGImageSourceCopyProperties(gifSource, NULL);
if (properties) {
CFDictionaryRef gif = CFDictionaryGetValue(properties, kCGImagePropertyGIFDictionary);
if (gif) {
CFTypeRef loop = CFDictionaryGetValue(gif, kCGImagePropertyGIFLoopCount);
if (loop) {
//如果loop == NULL，表示不循环播放，当loopCount == 0时，表示无限循环；
CFNumberGetValue(loop, kCFNumberNSIntegerType, &loopCount);
};
}
}
CFRelease(gifSource); return loopCount;
} //获取GIF图片每帧的时长
- (NSTimeInterval)gifImageDeleyTime:(CGImageSourceRef)imageSource index:(NSInteger)index {
NSTimeInterval duration = ;
CFDictionaryRef imageProperties = CGImageSourceCopyPropertiesAtIndex(imageSource, index, NULL);
if (imageProperties) {
CFDictionaryRef gifProperties;
BOOL result = CFDictionaryGetValueIfPresent(imageProperties, kCGImagePropertyGIFDictionary, (const void **)&gifProperties);
if (result) {
const void *durationValue;
if (CFDictionaryGetValueIfPresent(gifProperties, kCGImagePropertyGIFUnclampedDelayTime, &durationValue)) {
duration = [(__bridge NSNumber *)durationValue doubleValue];
if (duration < ) {
if (CFDictionaryGetValueIfPresent(gifProperties, kCGImagePropertyGIFDelayTime, &durationValue)) {
duration = [(__bridge NSNumber *)durationValue doubleValue];
}
}
}
}
} return duration;
} @end