来自本地通知的附件中的图像未显示在UNNotificationContentExtension中

Question

我一直在研究iOS10中引入的丰富通知体验，并坚持将图像作为附件传递给UNNotificationContentExtension。

这是我的ContentExtension：

class NotificationViewController: UIViewController, UNNotificationContentExtension {

    @IBOutlet weak var attachmentImage: UIImageView!

    func didReceive(_ notification: UNNotification) {

        if let attachment = notification.request.content.attachments.first {
            if attachment.url.startAccessingSecurityScopedResource() {
                attachmentImage.image = UIImage(contentsOfFile: attachment.url.path)
                attachment.url.stopAccessingSecurityScopedResource()
            }
        }
    }
}

作为教程，我一直关注Advanced Notifications video from WWDC。 我已经检查了 - UIImage我正在分配给UIImageView：

• 不 nil
• 具有适当的CGSize（191x191）
• attachment.url.path等于/var/mobile/Library/SpringBoard/PushStore/Attachments/<bundle of app>/<...>.png

以下是我从应用发送本地通知的方式：

    let content = UNMutableNotificationContent()
    content.title = "Sample title"
    content.body = "Sample body"
    content.categoryIdentifier = "myNotificationCategory"

    let attachement = try! UNNotificationAttachment(identifier: "image",
                                                                url: Bundle.main.url(forResource: "cat", withExtension: "png")!,
                                                                options: nil)

    content.attachments = [ attachement ]

    let request = UNNotificationRequest(identifier:requestIdentifier, content: content, trigger: nil)
    UNUserNotificationCenter.current().delegate = self
    UNUserNotificationCenter.current().add(request){(error) in
        if (error != nil){
        }
    }

“cat.png”只是我添加到proj的虚拟资源。

正如你所看到的，通知显示了pic，所以我认为，我正确地发送它，但是在扩展状态（NotificationViewController）中，我从未成功显示相同的图像。< / p>

我做错了什么？ 谢谢！

Answer 1

使用contentsOfFile创建UIImage时，UIImage对象仅读取图像标题，指示基本信息，如图像大小等。

因此，请尝试将stopAccessingSecurityScopedResource移至[NotificationViewController dealloc]。

或使用以下内容：

• objective-c 代码：

  NSData *imageData = [NSData dataWithContentsOfURL:imageURL];
  UIImage *image = [UIImage imageWithData:imageData];
  

• swift 代码：

  let imageData = NSData(contentsOf: attachment.url)
  let image = UIImage(data: imageData! as Data)
  

没有文件说contentsOfFile只读取图像标题。但是当我运行以下代码时：

NSString *docFolderPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject];
NSString *pngPath = [docFolderPath stringByAppendingPathComponent:@"test.png"];    
UIImage *image = [UIImage imageWithContentsOfFile:pngPath];
[[NSFileManager defaultManager] removeItemAtPath:pngPath error:nil];
imageView.image = image;

发生错误：

ImageIO: createDataWithMappedFile:1322:  'open' failed '/Users/fanjie/Library/Developer/CoreSimulator/Devices/FFDFCA06-A75E-4B54-9FC2-8E2AAE3B1405/data/Containers/Data/Application/E2D26210-4A53-424E-9FE8-D522CFD4FD9E/Documents/test.png'
     error = 2 (No such file or directory)

所以我得出结论，UIImage contentsOfFile只读取图像标题。

Answer 2

感谢@jeffery，

以下是通知扩展名中显示的图像的确切代码：

if let attachment = notification.request.content.attachments.first {
            if attachment.url.startAccessingSecurityScopedResource() {
                let data = NSData(contentsOfFile: attachment.url.path);
                self. attachmentImage?.image = UIImage(data: data! as Data);
                attachment.url.stopAccessingSecurityScopedResource()
            }
        }