前言
许多项目需要加载GIF图片，但是在直接使用UIImageView加载存在许多问题，于是查找资料做了一个加载GIF的Demo，思路来源https://github.com/YouXianMing/Animations 在链接里边，已经给出了解决办法，Demo只是将功能剥离，简单封装了一下。
思路
使用FLAnimatedImage来加载GIF图片，再利用SDWebImage来做缓存，话不多说，直接上代码。
使用方法
导入头文件#import "GIFView.h"
创建GIFView，添加到视图上
GIFView *view = [[GIFView alloc] initWithFrame:CGRectMake(0, 200, self.view.frame.size.width, 300)];
view.url = @"http://upload-images.jianshu.io/upload_images/1979970-9d2b1cc945099612.gif?imageMogr2/auto-orient/strip";
[self.view addSubview:view];
GIFView内部代码
@interface GIFView()
/**GIF视图*/
@property (nonatomic,weak)FLAnimatedImageView *gifImageView;
@end
@implementation GIFView
-(instancetype)initWithFrame:(CGRect)frame
{
if (self = [super initWithFrame:frame])
{
[self initUI];
}
return self;
}
- (void)initUI
{
//创建FLAnimatedImageView,继承自UIView
FLAnimatedImageView *gifImageView = [[FLAnimatedImageView alloc] init];
gifImageView.frame = self.frame;
[self addSubview:gifImageView];
_gifImageView = gifImageView;
}
-(void)setUrl:(NSString *)url
{
_url = url;
//将GIF转换成Data
NSData *gifImageData = [self imageDataFromDiskCacheWithKey:url];
//沙盒存在，直接加载显示
if (gifImageData)
{
[self animatedImageView:_gifImageView data:gifImageData];
//沙盒不存在，网络获取
} else
{
__weak __typeof(self) weakSelf = self;
NSURL *newUrl = [NSURL URLWithString:url];
[[SDWebImageDownloader sharedDownloader] downloadImageWithURL:newUrl
options:0
progress:nil
completed:^(UIImage *image, NSData *data, NSError *error, BOOL finished) {
[[[SDWebImageManager sharedManager] imageCache] storeImage:image
recalculateFromImage:NO
imageData:data
forKey:newUrl.absoluteString
toDisk:YES];
//主线程显示
dispatch_async(dispatch_get_main_queue(), ^{
[weakSelf animatedImageView:_gifImageView data:data];
});
}];
}
}
//通过数据创建GIF
- (void)animatedImageView:(FLAnimatedImageView *)imageView data:(NSData *)data
{
FLAnimatedImage *gifImage = [FLAnimatedImage animatedImageWithGIFData:data];
imageView.frame = CGRectMake(0, 0, self.frame.size.width, self.frame.size.height);
imageView.animatedImage = gifImage;
imageView.alpha = 0.f;
[UIView animateWithDuration:1.f animations:^{
imageView.alpha = 1.f;
}];
}
//从沙盒读取
- (NSData *)imageDataFromDiskCacheWithKey:(NSString *)key
{
NSString *path = [[[SDWebImageManager sharedManager] imageCache] defaultCachePathForKey:key];
return [NSData dataWithContentsOfFile:path];
}
效果图
这里需要注意要用真机测试，模拟器测试会看到卡顿现象
真机效果图.gif
声明
在这里说明下，只是简单的剥离功能，封装了一下，方便大家使用。Demo地址在这里https://github.com/JmoVxia/GIFDemo
