ios - 从 URL 将图像保存到库，重命名并使用 Swift 共享

Question

我想从我自己的 iOS 应用程序将图像分享到 Instagram，我在整个项目中使用 Kingfisher 下载和缓存图像并在 UIImageViews 中显示它们，但这次我想做一些不同的事情。

基本上，我从带有图像 url 的 API 获得响应，我想

1. 使用 URL 将图像下载到库中

关于使用 objective-C 有一堆问题

 UIImageWriteToSavedPhotosAlbum 

但我使用的是 Swift。

1. 使用 .igo 扩展重命名(instagram 独有)

不确定如何解决这个问题，这取决于第 1 条。

1. 然后我可以像这样分享它

           let image = UIImage(named: "downloadedImage")
           let objectsToShare: [AnyObject] = [ image! ]
           let activityViewController = UIActivityViewController(activityItems: objectsToShare, applicationActivities: nil)
           activityViewController.popoverPresentationController?.sourceView = self.view
   
   
           activityViewController.excludedActivityTypes = [ UIActivityTypeAirDrop, UIActivityTypePostToFacebook ]
   
   
           self.presentViewController(activityViewController, animated: true, completion: nil)
   

或者我可以使用 instagram Hook :

 instagram://library?LocalIdentifier=\(localID)

专门针对 Swift 的文档很少。我该怎么做？我只需要朝着正确的方向插入。

Answer 1

听起来您已经知道如何使用 Kingfisher 并从 URL 中检索 UIImage。所以我要提供的是将图像保存到文档目录并检索它以共享的信息。

检索正确的目录 URL

func getDocumentsDirectory() -> URL {
    let paths = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
    let documentsDirectory = paths[0]
    return documentsDirectory
}

将图像保存到该目录

func saveImage (image: UIImage, filename: String ){
    print("Saving image with name \(filename)")
    if let data = UIImagePNGRepresentation(image) {
        let fullURL = getDocumentsDirectory().appendingPathComponent(filename)
        try? data.write(to: fullURL)
    }
}

从目录中检索图像

func loadImageFromName(name: String) -> UIImage? {
    print("Loading image with name \(name)")
    let path = getDocumentsDirectory().appendingPathComponent(name).path

    let image = UIImage(contentsOfFile: path)

    if image == nil {

        print("missing image at: \(path)")
    }
    return image
}

分享图片

func share(shareText shareText:String?,shareImage:UIImage?){
   var objectsToShare = [AnyObject]()
   if let shareTextObj = shareText{
      objectsToShare.append(shareTextObj)
   }
   if let shareImageObj = shareImage{
      objectsToShare.append(shareImageObj)
   }

   if shareText != nil || shareImage != nil{
      let activityViewController = UIActivityViewController(activityItems: objectsToShare, applicationActivities: nil)
      activityViewController.popoverPresentationController?.sourceView = self.view

      present(activityViewController, animated: true, completion: nil)
   }else{
     print("There is nothing to share")
   }
}

如何使用

let img: UIImage = UIImage() // Replace this with your image from your URL
saveImage(image: img, filename: "newImage.igo") //This is where you change your extension name

let newImage: UIImage = loadImageFromName(name: "newImage.igo") //Retrieve your image with the correct extension

share(shareText: "Image going to Instagram", shareImage: newImage) //Present Activity VC.

正如 DFD 指出的那样，您可以从共享 VC 中排除某些项目以仅允许您需要的内容。