iOS 两种加载GIF图片区别
现在开发不论是广告页，新手引导图或者发送图片都有GIF了，但是很多时候不同的加载对内存也有不同的负担
一般大家现在都用WKWebView或者SDWebImage，YYImage来加载比较对内存不会占用那么多
例如我一般都是用WKWebView，不过听说YYImage对gif图播放支持比较好点,你有空可以试试那个。
// 读取gif图片数据
NSData *gif = [NSDatadataWithContentsOfFile: [[NSBundlemainBundle] pathForResource:@"angelBird"ofType:@"gif"]];
// webview生成
WKWebView *webView = [[WKWebViewalloc] initWithFrame:CGRectMake(0,0, self.view.frame.size.width,self.view.frame.size.height)];
[webView loadData:gifMIMEType:@"image/gif"characterEncodingName:nilbaseURL:nil];
[self.viewaddSubview:webView];
另一种就是看着别人然后自己也写了，原生的了，继承ImageView
@interface RQimageView : UIImageView
-(void)yh_setImage:(NSURL *)imageUrl;
@end
#import "RQimageView.h"
#import
@implementation RQimageView
-(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 = [[NSMutableArrayalloc]init];
//存放每一帧播放的时间
NSMutableArray * timeArray = [[NSMutableArrayalloc]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 = [[NSMutableArrayalloc]init];
//存放每张图片的高度
NSMutableArray * heightArray = [[NSMutableArrayalloc]init];
//遍历
for (size_t i=0; i
CGImageRef image =CGImageSourceCreateImageAtIndex(source, i,NULL);
[imageArray addObject:(__bridgeUIImage *)(image)];
CGImageRelease(image);
//获取图片信息
NSDictionary * info = (__bridgeNSDictionary*)CGImageSourceCopyPropertiesAtIndex(source, i,NULL);
CGFloat width = [[infoobjectForKey:(__bridgeNSString *)kCGImagePropertyPixelWidth]floatValue];
CGFloat height = [[infoobjectForKey:(__bridgeNSString *)kCGImagePropertyPixelHeight]floatValue];
[widthArray addObject:[NSNumbernumberWithFloat:width]];
[heightArray addObject:[NSNumbernumberWithFloat:height]];
NSDictionary * timeDic = [infoobjectForKey:(__bridgeNSString *)kCGImagePropertyGIFDictionary];
CGFloat time = [[timeDicobjectForKey:(__bridgeNSString *)kCGImagePropertyGIFDelayTime]floatValue];
allTime+=time;
[timeArray addObject:[NSNumbernumberWithFloat:time]];
CFRelease((__bridgeCFTypeRef)(info));
}
CFRelease(source);
dataBlock(imageArray,timeArray,allTime,widthArray,heightArray);
}
-(void)yh_setImage:(NSURL *)imageUrl{
__weakid __self = self;
[selfgetGifImageWithUrk:imageUrlreturnData:^(NSArray<UIImage *> *imageArray,NSArray<NSNumber *> *timeArray,CGFloat totalTime, NSArray<NSNumber *> *widths,NSArray<NSNumber *> *heights) {
//添加帧动画
CAKeyframeAnimation *animation = [CAKeyframeAnimationanimationWithKeyPath:@"contents"];
NSMutableArray * times = [[NSMutableArrayalloc]init];
float currentTime =0;
//设置每一帧的时间占比
for (int i=0; i
[times addObject:[NSNumbernumberWithFloat:currentTime/totalTime]];
currentTime+=[timeArray[i] floatValue];
}
[animation setKeyTimes:times];
[animation setValues:imageArray];
[animation setTimingFunction:[CAMediaTimingFunctionfunctionWithName:kCAMediaTimingFunctionLinear]];
//设置循环
animation.repeatCount=MAXFLOAT;
//设置播放总时长
animation.duration = totalTime;
//Layer层添加
[[(UIImageView *)__selflayer]addAnimation:animationforKey:@"gifAnimation"];
}];
}
@end
调用
NSURL * url = [[NSURLalloc]initFileURLWithPath:[[NSBundlemainBundle] pathForResource:@"angelBird.gif"ofType:nil]];
RQimageView *imgView = [[RQimageViewalloc]initWithFrame:CGRectMake(0,0, self.view.frame.size.width,self.view.frame.size.height)];
[imgView yh_setImage:url];
[self.viewaddSubview:imgView];
我开发的时候对着两种做过比较，开始觉得自己写了用特别有成就感，然后发现用第二种内存飙到103MB然而用WKwebView还好，才11MB左右，原因你看代码也知道啦，这样循环加载播放，不彪才怪，哈哈