iphone - didFinishPickingMediaWithInfo 返回零照片

Question

我正在努力使用

捕获 4.0 中返回的图像

- (void)imagePickerController:(UIImagePickerController *)picker 
    didFinishPickingMediaWithInfo:(NSDictionary *)info
{
    [[picker parentViewController] dismissModalViewControllerAnimated:YES]; 

    // MediaType can be kUTTypeImage or kUTTypeMovie. If it's a movie then you
    // can get the URL to the actual file itself. This example only looks for images.
    //   
    NSString* mediaType = [info objectForKey:UIImagePickerControllerMediaType];
    // NSString* videoUrl = [info objectForKey:UIImagePickerControllerMediaURL];

    // Try getting the edited image first. If it doesn't exist then you get the
    // original image.
    //
    if (CFStringCompare((CFStringRef) mediaType,  kUTTypeImage, 0) == kCFCompareEqualTo) {               
        UIImage* picture = [info objectForKey:UIImagePickerControllerEditedImage];
        if (!picture)
            picture = [info objectForKey:UIImagePickerControllerOriginalImage];             

        // **picture is always nil
            // info dictionary count = 1


    }

}

发生的情况是信息字典总是返回一个条目:

{ UIImagePickerControllerMediaType = "public.image";

这很棒，但从来没有图像。

我使用了这个论坛上的一个很好的例子来做到这一点，我很确定调用是正确的，但从来没有图像。

提前致谢!

Answer 1

我知道这已经是几个月后的事了，但我为此苦苦挣扎了几个小时，并在这个网站和 iphonedevsdk.com 上发现了同样的问题，但从未找到有效的答案。

总而言之，如果图像是从相机胶卷/照片库中选取的，则它可以正常工作，但如果图像是用相机拍摄的新照片，则它永远不会工作。好吧，以下是如何让它同时适用于两者:

在尝试对信息字典执行任何操作之前，您必须先关闭并释放 UIImagePickerController。非常清楚:

这不起作用:

- (void)imagePickerController:(UIImagePickerController *)picker 
                      didFinishPickingMediaWithInfo:(NSDictionary *)info {

          // No good with the edited image (if you allowed editing)
  myUIImageView.image = [info objectForKey:UIImagePickerControllerEditedImage];
          // AND no good with the original image
  myUIImageView.image = [info objectForKey:UIImagePickerControllerOriginalImage];
          // AND no doing some other kind of assignment
  UIImage *myImage = [info objectForKey:UIImagePickerControllerEditedImage];

  [picker dismissModalViewControllerAnimated:YES];
  [picker release];
}

在所有这些情况下，图像都为零。

但是，通过释放 UIImagePickerController 首先...

这确实有效:

- (void)imagePickerController:(UIImagePickerController *)picker 
                      didFinishPickingMediaWithInfo:(NSDictionary *)info {

  [picker dismissModalViewControllerAnimated:YES];
  [picker release];

          // Edited image works great (if you allowed editing)
  myUIImageView.image = [info objectForKey:UIImagePickerControllerEditedImage];
          // AND the original image works great
  myUIImageView.image = [info objectForKey:UIImagePickerControllerOriginalImage];
          // AND do whatever you want with it, (NSDictionary *)info is fine now
  UIImage *myImage = [info objectForKey:UIImagePickerControllerEditedImage];
}

非常简单，但这就是全部。