@interface ViewController () <UIImagePickerControllerDelegate, UINavigationControllerDelegate>

- (void)getImageFromIpc
{
  // 1.判斷相冊是否可以打開
  if (![UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary]) return;
  // 2. 創(chuàng)建圖片選擇控制器
  UIImagePickerController *ipc = [[UIImagePickerController alloc] init];
  /**
   typedef NS_ENUM(NSInteger, UIImagePickerControllerSourceType) {
   UIImagePickerControllerSourceTypePhotoLibrary, // 相冊
   UIImagePickerControllerSourceTypeCamera, // 用相機拍攝獲取
   UIImagePickerControllerSourceTypeSavedPhotosAlbum // 相簿
   }
   */
  // 3. 設(shè)置打開照片相冊類型(顯示所有相簿) 
  ipc.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
  // ipc.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;
  // 照相機
  // ipc.sourceType = UIImagePickerControllerSourceTypeCamera;
  // 4.設(shè)置代理
  ipc.delegate = self;
  // 5.modal出這個控制器
  [self presentViewController:ipc animated:YES completion:nil];
}

#pragma mark -- <UIImagePickerControllerDelegate>--
// 獲取圖片后的操作
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info
{
  // 銷毀控制器
  [picker dismissViewControllerAnimated:YES completion:nil];

  // 設(shè)置圖片
  self.imageView.image = info[UIImagePickerControllerOriginalImage];
}

#import <AssetsLibrary/AssetsLibrary.h>

- (void)getOriginalImages
{
  // 獲得所有的自定義相簿
  PHFetchResult<PHAssetCollection *> *assetCollections = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeAlbum subtype:PHAssetCollectionSubtypeAlbumRegular options:nil];
  // 遍歷所有的自定義相簿
  for (PHAssetCollection *assetCollection in assetCollections) {
    [self enumerateAssetsInAssetCollection:assetCollection original:YES];
  }

  // 獲得相機膠卷
  PHAssetCollection *cameraRoll = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeSmartAlbum subtype:PHAssetCollectionSubtypeSmartAlbumUserLibrary options:nil].lastObject;
  // 遍歷相機膠卷,獲取大圖
  [self enumerateAssetsInAssetCollection:cameraRoll original:YES];
}

- (void)getThumbnailImages
{
  // 獲得所有的自定義相簿
  PHFetchResult<PHAssetCollection *> *assetCollections = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeAlbum subtype:PHAssetCollectionSubtypeAlbumRegular options:nil];
  // 遍歷所有的自定義相簿
  for (PHAssetCollection *assetCollection in assetCollections) {
    [self enumerateAssetsInAssetCollection:assetCollection original:NO];
  }
  // 獲得相機膠卷
  PHAssetCollection *cameraRoll = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeSmartAlbum subtype:PHAssetCollectionSubtypeSmartAlbumUserLibrary options:nil].lastObject;
  [self enumerateAssetsInAssetCollection:cameraRoll original:NO];
}

/**
 * 遍歷相簿中的所有圖片
 * @param assetCollection 相簿
 * @param original    是否要原圖
 */
- (void)enumerateAssetsInAssetCollection:(PHAssetCollection *)assetCollection original:(BOOL)original
{
  NSLog(@"相簿名:%@", assetCollection.localizedTitle);

  PHImageRequestOptions *options = [[PHImageRequestOptions alloc] init];
  // 同步獲得圖片, 只會返回1張圖片
  options.synchronous = YES;

  // 獲得某個相簿中的所有PHAsset對象
  PHFetchResult<PHAsset *> *assets = [PHAsset fetchAssetsInAssetCollection:assetCollection options:nil];
  for (PHAsset *asset in assets) {
    // 是否要原圖
    CGSize size = original ? CGSizeMake(asset.pixelWidth, asset.pixelHeight) : CGSizeZero;

    // 從asset中獲得圖片
    [[PHImageManager defaultManager] requestImageForAsset:asset targetSize:size contentMode:PHImageContentModeDefault options:options resultHandler:^(UIImage * _Nullable result, NSDictionary * _Nullable info) {
      NSLog(@"%@", result);
    }];
  }
}