將照片保存到相機膠捲並確保其實際保存

Question

我正在以這種方式將UIImage保存到相機膠捲。

UIImageWriteToSavedPhotosAlbum(finalPicture.image, nil, nil, nil);

但是，如果用戶拒絕允許我們訪問他們的照片會發生什麼......我怎麼能告訴，這已經發生了，顯示錯誤消息？

Answer 1

要保存圖像的相機膠捲我使用ALAssetsLibrary這樣的方法：

//Called after taking the photo with the camera or selected the image from the gallery 
- (void)imagePickerController:(UIImagePickerController *) Picker didFinishPickingMediaWithInfo:(NSDictionary *)info { 

NSURL *referenceURL; 

if(Picker.sourceType==UIImagePickerControllerSourceTypeCamera){ 

    UIImage* takenImage=info[UIImagePickerControllerOriginalImage]; 

    ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init]; 
    // Request to save the image to camera roll 
    [library writeImageToSavedPhotosAlbum:[takenImage CGImage] orientation:(ALAssetOrientation)[takenImage imageOrientation] completionBlock:^(NSURL *assetURL, NSError *error){ 
     if (error) { 
      //NOT SAVED 
      //DISPLAY ERROR THE PICTURE CAN'T BE SAVED 
     } else { 
      //SAVED 
     } 
    }];   

} 
}else{ 
//Selected from gallery 
} 

還記得，你必須先檢查照相機。

if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) 
    { 
     //The camera is available 
    }else{ 
     //No camera available 
    }