使用Photos框架封装一个单选和多选的照片选择

选择照片.gif

GitHub地址:https://github.com/zhuxinleibandou/ZXLChoosePhoto

Photos框架是iOS新引入进来的，具体的介绍可以百度一下，今天这里主要是写一个照片封装库的心得

上干货～～

引用：http://www.jianshu.com/p/42e5d2f75452

照片库中有两种资源可供获取：PHAsset和PHCollection，前者代表图像或视频对象，后者是前者的集合或自身类型的集合。PHCollection是个基类，有PHAssetCollection和PHCollectionList两个子类，分别代表 Photos 里的相册和文件夹

1.获取相册集

- (PHFetchResult *)getAllCollection{
    PHFetchResult *smartAlbums = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeSmartAlbum subtype:PHAssetCollectionSubtypeAlbumRegular options:nil];
    return smartAlbums;
}

2.获取相册内所有照片资源

- (NSMutableArray *)getAllAssetInPhotoAblumWithAscending:(BOOL)ascending withCollection:(PHCollection *)collection
{
    PHFetchOptions *option = [[PHFetchOptions alloc] init];
    //ascending 为YES时，按照照片的创建时间升序排列;为NO时，则降序排列
    option.sortDescriptors = @[[NSSortDescriptor sortDescriptorWithKey:@"creationDate" ascending:ascending]];
    option.predicate = [NSPredicate predicateWithFormat:@"mediaType == %ld", PHAssetMediaTypeImage];
    option.includeAssetSourceTypes = PHAssetSourceTypeUserLibrary;      //设置数据源为本地用户的
    NSMutableArray *assets = [NSMutableArray array];
    BDLog(@"%@",collection.localizedTitle);
    if ([collection isKindOfClass:[PHAssetCollection class]]) {
            PHAssetCollection *assetCollection = (PHAssetCollection *)collection;
            PHFetchResult *result = [PHAsset fetchAssetsInAssetCollection:assetCollection options:option];
            [result enumerateObjectsUsingBlock:^(id  _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
                PHAsset *asset = (PHAsset *)obj;
                if (!asset.hidden) {    //是否被隐藏
                    NSLog(@"照片名%@", [asset valueForKey:@"filename"]);
                    [assets addObject:asset];
                }
            }];
    }
    return assets;
}

3.解析照片

- (void)accessToImageAccordingToTheAsset:(PHAsset *)asset size:(CGSize)size resizeMode:(PHImageRequestOptionsResizeMode)resizeMode completion:(void(^)(UIImage *image,NSDictionary *info))completion
{
    PHImageRequestOptions *option = [[PHImageRequestOptions alloc] init];
    //仅显示缩略图，不控制质量显示
    /**
     PHImageRequestOptionsResizeModeNone,
     PHImageRequestOptionsResizeModeFast, //根据传入的size，迅速加载大小相匹配(略大于或略小于)的图像
     PHImageRequestOptionsResizeModeExact //精确的加载与传入size相匹配的图像
     */
    option.resizeMode = resizeMode;
    option.networkAccessAllowed = false; //不允许网络请求，icold图片请求不到
    //param：targetSize 即你想要的图片尺寸，若想要原尺寸则可输入PHImageManagerMaximumSize
    //解析缩略图
    [[PHCachingImageManager defaultManager] requestImageForAsset:asset targetSize:size contentMode:PHImageContentModeAspectFit options:option resultHandler:^(UIImage * _Nullable image, NSDictionary * _Nullable info) {
        //解析出来的图片
        completion(image,info);
    }];
    
}