ios7 – UIImagePickerController图像类型

我的应用程序允许用户从设备相机胶卷中选择图像.我想验证所选图像的格式是PNG还是JPG图像.

是否有可能在 – (void)imagePickerController中执行此操作：(UIImagePickerController *)选择器didFinishPickingMediawithInfo：(NSDictionary *)info委托方法？

解决方法

是的,您可以在委托回调中执行此操作.您可能已经注意到UIImagePickerControllerMediaType信息字典键将返回一个“public.image”字符串作为UTI,这不足以满足您的需要.但是,这可以通过使用与信息字典中的UIImagePickerControllerReferenceURL键关联的URL来完成.例如,实现可能类似于下面的方法.

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediawithInfo:(NSDictionary *)info
{
    UIImage *image = info[UIImagePickerControllerEditedImage];
    NSURL *assetURL = info[UIImagePickerControllerReferenceURL];

    Nsstring *extension = [assetURL pathExtension];
    CFStringRef imageUTI = (UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension,(__bridge CFStringRef)extension,NULL));

    if (UTTypeConformsTo(imageUTI,kUTTypeJPEG))
    {
        // Handle JPG
    }
    else if (UTTypeConformsTo(imageUTI,kUTTypePNG))
    {
        // Handle PNG
    }
    else
    {
        NSLog(@"Unhandled Image UTI: %@",imageUTI);
    }

    CFRelease(imageUTI);

    [self.imageView setimage:image];

    [picker dismissViewControllerAnimated:YES completion:NULL];
}

您还需要链接MobileCoreServices.framework并添加#import< MobileCoreServices / MobileCoreServices.h>