图片选择器，看cocoachina发现一个有趣的框架，很好用，分享一下，其实做出该功能我之前写过一篇博客，使用转场动画写的，就是图片的手势缩放没写，有兴趣可以看看
效果图：
github地址：https://github.com/coder-zwz/MJPhotoBrowser
使用：
#import "ViewController.h"
#import "MJPhotoBrowser.h"
@interface ViewController ()
{
NSArray *_urls;
}
@end @implementation ViewController - (void)viewDidLoad
{
[super viewDidLoad];
self.view.backgroundColor = [UIColor groupTableViewBackgroundColor];
// 0.图片链接
_urls = @[@"http://ww4.sinaimg.cn/thumbnail/7f8c1087gw1e9g06pc68ug20ag05y4qq.gif", @"http://ww3.sinaimg.cn/thumbnail/8e88b0c1gw1e9lpr0nly5j20pf0gygo6.jpg", @"http://ww4.sinaimg.cn/thumbnail/8e88b0c1gw1e9lpr1d0vyj20pf0gytcj.jpg", @"http://ww3.sinaimg.cn/thumbnail/8e88b0c1gw1e9lpr1xydcj20gy0o9q6s.jpg", @"http://ww2.sinaimg.cn/thumbnail/8e88b0c1gw1e9lpr2n1jjj20gy0o9tcc.jpg", @"http://ww2.sinaimg.cn/thumbnail/8e88b0c1gw1e9lpr39ht9j20gy0o6q74.jpg", @"http://ww3.sinaimg.cn/thumbnail/8e88b0c1gw1e9lpr3xvtlj20gy0obadv.jpg", @"http://ww4.sinaimg.cn/thumbnail/8e88b0c1gw1e9lpr4nndfj20gy0o9q6i.jpg", @"http://ww3.sinaimg.cn/thumbnail/8e88b0c1gw1e9lpr57tn9j20gy0obn0f.jpg"]; // 1.创建9个UIImageView
UIImage *placeholder = [UIImage imageNamed:@"timeline_image_loading.png"];
CGFloat width = 80;
CGFloat height = 80;
CGFloat margin = 5;
CGFloat startX = (self.view.frame.size.width - 3 * width - 2 * margin) * 0.5;
CGFloat startY = 80;
for (int i = 0; i<9; i++) {
UIImageView *imageView = [[UIImageView alloc] init];
[self.view addSubview:imageView]; // 计算位置
int row = i/3;
int column = i%3;
CGFloat x = startX + column * (width + margin);
CGFloat y = startY + row * (height + margin);
imageView.frame = CGRectMake(x, y, width, height); // 下载图片
[imageView setImageURLStr:_urls[i] placeholder:placeholder]; // 事件监听
imageView.tag = i;
imageView.userInteractionEnabled = YES;
[imageView addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapImage:)]]; // 内容模式
imageView.clipsToBounds = YES;
imageView.contentMode = UIViewContentModeScaleAspectFill;
}
} - (void)tapImage:(UITapGestureRecognizer *)tap
{
NSInteger count = _urls.count;
// 1.封装图片数据
NSMutableArray *photos = [NSMutableArray arrayWithCapacity:count];
for (int i = 0; i<count; i++) {
// 替换为中等尺寸图片
NSString *url = [_urls[i] stringByReplacingOccurrencesOfString:@"thumbnail" withString:@"bmiddle"];
MJPhoto *photo = [[MJPhoto alloc] init];
photo.url = [NSURL URLWithString:url]; // 图片路径
photo.srcImageView = self.view.subviews[i]; // 来源于哪个UIImageView
[photos addObject:photo];
} // 2.显示相册
MJPhotoBrowser *browser = [[MJPhotoBrowser alloc] init];
browser.currentPhotoIndex = tap.view.tag; // 弹出相册时显示的第一张图片是？
browser.photos = photos; // 设置所有的图片
[browser show];
} @end