• 之前的代码 自己看看

#pragma mark 相册操作
- (void)getOriginalImages{       
//获取所有自定义相簿    
    PHFetchResult*assetCollections = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeSmartAlbum subtype:PHAssetCollectionSubtypeAlbumRegular options:nil];   
//便利所有相册簿    
    for (PHAssetCollection *assetCollection in assetCollections) {       
        [self enumerateAssetsInAssetCollection:assetCollection original:YES];       
      NSLog(@"相册名%@",assetCollection.localizedTitle);    
    }   
//    PHAssetCollection *cameraRoll = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeSmartAlbum subtype:PHAssetCollectionSubtypeSmartAlbumUserLibrary options:nil].lastObject;
//    [self enumerateAssetsInAssetCollection:cameraRoll original:YES];
}
//获取所有相册中的缩略图 //没用
- (void)getThumbnailImages{        
    PHFetchResult*assetCollections = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeSmartAlbum subtype:PHAssetCollectionSubtypeAlbumRegular options:nil];        
    for (PHAssetCollection *assetCollection in assetCollections) {        
        [self enumerateAssetsInAssetCollection:assetCollection original:NO];  
     }
    PHAssetCollection *cameraRoll = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeAlbum subtype:PHAssetCollectionSubtypeSmartAlbumUserLibrary options:nil].lastObject;   
    [self enumerateAssetsInAssetCollection:cameraRoll original:NO];
}
/* 遍历相册中的原图 @param assetCollection 相册 @param original 是否要原图  */
- (void)enumerateAssetsInAssetCollection:(PHAssetCollection *)assetCollection original:(BOOL)original{        
    PHImageRequestOptions *options = [[PHImageRequestOptions alloc] init];    
//同步获得智慧返回一张    options.synchronous = YES;      
//获得某个相册中所有的phasset对象   
    PHFetchResult*assets = [PHAsset fetchAssetsInAssetCollection:assetCollection options:nil];
//    NSLog(@"图片数量:%lu",(unsigned long)assets.count);
    if(assets.count){
        ZCCPhoneAlbumModel *albumModel = [[ZCCPhoneAlbumModel alloc] init];
//        NSLog(@"相册名%@",assetCollection.localizedTitle);
//相册名给对象
        albumModel.photoAlbumName = assetCollection.localizedTitle;
        NSMutableArray *picsArray = [NSMutableArray array];
        for (PHAsset *asset in assets) {
//        CGSize size = original ? CGSizeMake(asset.pixelWidth, asset.pixelHeight) :         CGSizeZero;
//宽大于高 就把高变成 asset.pixelHeight * COLLECTIONWIDTH/asset.pixelHeight
            CGFloat width = 0;
            CGFloat height = 0;
//宽大于高 压缩高
            if(asset.pixelWidth > asset.pixelHeight){
                width = asset.pixelWidth * COLLECTIONWIDTH/asset.pixelHeight;
                height = COLLECTIONWIDTH;
            }else{//宽小于高 压缩宽
                width = COLLECTIONWIDTH;
                height = asset.pixelHeight * COLLECTIONWIDTH/asset.pixelWidth;
            }
            CGSize size = CGSizeMake(width, height);
//从asset中获得图片
            [[PHImageManager defaultManager] requestImageForAsset:asset 
                                             targetSize:size 
                                             contentMode:PHImageContentModeDefault 
                                             options:options 
                                             resultHandler:^(UIImage * _Nullable result, NSDictionary * _Nullable info) {
//                NSLog(@"%@",result);
                                                [picsArray addObject:result];
                                             }];
         }
          albumModel.photos = picsArray;
          //把这个相册对象添加到相册数组中
          [self.photoAlbums addObject:albumModel];
     }
}
其实这里可以通过 打开collectionView获取contentoffsize来判断当前滑动位置 然后 加载 总图片的对应阶段图片 边滑动边加载 这样就不会造成刚点开的卡顿了  有空实现一下。