整理UIImagePickerController、儲存圖片到相簿問題，

整理UIImagePickerController、儲存圖片到相簿問題，

//此方法在ios8.0系統上，之前用代碼建立的相簿，手動刪除它，再用這個庫去建立剛被刪除的相簿，這個時候方法回調是不會跑fail模組的，它走的是正常流程，但是帶回來的group卻是nil造成崩潰原因ALAssetsLibrary *assetsLibrary = [[ALAssetsLibrary alloc] init];[assetsLibrary addAssetsGroupAlbumWithName:@"iOSDevTip1" resultBlock:^(ALAssetsGroup *group12) {    [groups addObject:group12];} failureBlock:nil];

//為瞭解決iOS8.0以上系統下無法通過代碼建立被刪除過的同名相簿[[PHPhotoLibrary sharedPhotoLibrary] performChanges:^ {     [PHAssetCollectionChangeRequest creationRequestForAssetCollectionWithTitle:@"琳小兮"];      } completionHandler:^(BOOL success, NSError *error) {     if (!success) {         NSLog(@"---error:%@",error.userInfo);     } }];

補充

#pragma mark ----- 網路攝影機和相簿相關 -----// 判斷裝置是否有網路攝影機- (BOOL)isCameraAvailable {    return [UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera];}// 判斷前面的網路攝影機是否可用- (BOOL)isFrontCameraAvailable {    return [UIImagePickerController isCameraDeviceAvailable:UIImagePickerControllerCameraDeviceFront];}// 判斷後面的網路攝影機是否可用- (BOOL)isRearCameraAvailable {    return [UIImagePickerController isCameraDeviceAvailable:UIImagePickerControllerCameraDeviceRear];}// 判斷是否支援某種多媒體類型：拍照片、拍視頻- (BOOL)cameraSupportsMedia:(NSString *)paramMediaType sourceType:(UIImagePickerControllerSourceType)paramSourceType {    __block BOOL result = NO;    if ([paramMediaType length] == 0){        NSLog(@"Media type is empty.");        return NO;    }    NSArray *availableMediaTypes = [UIImagePickerController availableMediaTypesForSourceType:paramSourceType];    [availableMediaTypes enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL*stop) {        NSString *mediaType = (NSString *)obj;        if ([mediaType isEqualToString:paramMediaType]){            result = YES;            *stop = YES;        }            }];    return result;}// 判斷網路攝影機是否支援錄影- (BOOL)doesCameraSupportShootingVideos {    return [self cameraSupportsMedia:(NSString *)kUTTypeMovie sourceType:UIImagePickerControllerSourceTypeCamera];}// 判斷網路攝影機是否支援拍照- (BOOL)doesCameraSupportTakingPhotos {    return [self cameraSupportsMedia:(NSString *)kUTTypeImage sourceType:UIImagePickerControllerSourceTypeCamera];}#pragma mark ----- 相簿檔案選取相關 -----// 判斷相簿是否可用- (BOOL) isPhotoLibraryAvailable{    return [UIImagePickerController isSourceTypeAvailable: UIImagePickerControllerSourceTypePhotoLibrary];}// 判斷是否可以在相簿中選擇視頻- (BOOL) canUserPickVideosFromPhotoLibrary {    return [self cameraSupportsMedia:( NSString *)kUTTypeMovie sourceType:UIImagePickerControllerSourceTypePhotoLibrary];}// 判斷是否可以在相簿中選擇照片- (BOOL) canUserPickPhotosFromPhotoLibrary {    return [self cameraSupportsMedia:( NSString *)kUTTypeImage sourceType:UIImagePickerControllerSourceTypePhotoLibrary];}