如何从 uitextview 中提取 link 并从 link 加载图像，如 facebook 或 twitter？

Question

我想从 uitextview 中提取 link 并从 link 加载图像。例子就像这样 https://www.google.com/search?q=twitter+link&espv=2&biw=1380&bih=689&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiH5I2DsbXLAhVRJI4KHXCcD-YQ_AUIBigB#tbm=isch&q=twitter+link+preview&imgrc=ID-I2bdqhuiYZM%3A 。我该怎么做？

Answer 1

最简单的解决方案之一是从文本视图中检测 url，如果 url 有效则加载它并提取包含文档标题和几行文本的 header从响应 body，还从返回的响应加载任何图像，并将所有这些放在一个漂亮的 UI.

中

Answer 2

1. 将文本视图 属性 设置为：

2. 使用 -

   -(BOOL)textView:(UITextView *)textView shouldInteractWithURL:(NSURL *)URL inRange:(NSRange)characterRange
   {
   }
   

   得到url.

查看图片

当您点击 http://www.google.com 时，委托函数 shouldInteractWithURL 将检测到 url 被点击，您将在 URL 参数中获得 url。

3. 然后下载到imageview中显示。

Answer 3

这是代码。

- (void)viewDidLoad
{
   [super viewDidLoad];
    NSString * testStr=@"The world’s most popular camera is more advanced than ever. The 12-megapixel iSight camera captures sharp, detailed photos. It takes brilliant 4K video, up to four times the resolution of 1080p HD video. http://cdn2.gsmarena.com/vv/bigpic/apple-iphone-6s1.jpg. iPhone 6s also takes selfies worthy of a self-portrait with the new 5-megapixel FaceTime HD camera. And it introduces Live Photos, a new way to relive your favourite memories. It captures the moments just before and after your picture and sets it in motion with just the press of a finger.";
    [self identifyTextContent:testStr];
}

-(void)identifyTextContent :(NSString *)txtvwstr
{
     NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:txtvwstr];
     NSTextAttachment *textAttachment = [[NSTextAttachment alloc] init];
     NSDataDetector *detector = [NSDataDetector dataDetectorWithTypes:NSTextCheckingTypeLink error:nil];
     [detector enumerateMatchesInString:txtvwstr options:kNilOptions range:NSMakeRange(0, [txtvwstr length]) usingBlock:^(NSTextCheckingResult *result, NSMatchingFlags flags, BOOL *stop) {
      NSLog(@"Values: %@", result);
        if (result.resultType == NSTextCheckingTypeLink)
        {
           NSLog(@"matched: %@",result.URL);
         //**You can use [SDWebImage][1] library to download the image from detected url.**//
           NSData *data = [NSData dataWithContentsOfURL:result.URL];
           UIImage *img = [[UIImage alloc] initWithData:data];
           textAttachment.image = img;
           NSAttributedString *attrStringWithImage = [NSAttributedString attributedStringWithAttachment:textAttachment];
           [attributedString replaceCharactersInRange:result.range withAttributedString:attrStringWithImage];
        }
     }];
 //**HERE _txtVwData is my UITextView outlet.**
  _txtVwData.attributedText=attributedString;
}

希望对您有所帮助。 谢谢

这是输出屏幕。

Answer 4

我将答案 Payal Umraliya 转换为 swift

func imageText(text:String) {


    let style = NSMutableParagraphStyle()
    let myFont = UIFont(name: "roboto-Light", size: 19)


    let attributedString = NSMutableAttributedString.init(string: text, attributes: [NSParagraphStyleAttributeName:style, NSFontAttributeName: myFont!])

    let textAttachment = NSTextAttachment.init()
    let detector = try? NSDataDetector(types: NSTextCheckingResult.CheckingType.link.rawValue)

    detector?.enumerateMatches(in: text, options: [.withoutAnchoringBounds, .reportProgress], range:NSRange.init(location: 0, length: text.characters.count), using: { (result:NSTextCheckingResult?, flag:NSRegularExpression.MatchingFlags, stop:UnsafeMutablePointer?) in



        if (result?.resultType == NSTextCheckingResult.CheckingType.link) {
            let data = NSData(contentsOf: (result?.url)!)
            let image = UIImage.init(data: data! as Data)

            textAttachment.bounds = CGRect(x: 0, y: 0, width: 300, height: 200)

            textAttachment.image = image
            let attributedStringWithImage = NSAttributedString(attachment: textAttachment)
            attributedString.replaceCharacters(in: (result?.range)!, with: attributedStringWithImage)


        }
    })

    textView.attributedText = attributedString

}

或者在一篇文章中多张照片

func imageText(text:String) {

    let style = NSMutableParagraphStyle()

    let myFont = UIFont(name: "roboto-Light", size: 19)


    let attributedString = NSMutableAttributedString(string: text, attributes: [NSParagraphStyleAttributeName:style, NSFontAttributeName: myFont!])

    let detector = try? NSDataDetector(types: NSTextCheckingResult.CheckingType.link.rawValue)

    let matches = detector?.matches(in: text, options: .reportCompletion, range:NSRange(location: 0, length: text.characters.count))

            for match in matches! {

                let textAttachment = NSTextAttachment.init()

                let data = NSData(contentsOf: (match.url!))
                if data != nil{
                    let image = UIImage(data: data! as Data)

                    textAttachment.bounds = CGRect(x: 0, y: 0, width: 300, height: 200)
                    textAttachment.image = image
                    let attributedStringWithImage = NSAttributedString(attachment: textAttachment)
                    attributedString.replaceCharacters(in: (match.range), with: attributedStringWithImage)

                }
        }

    textView.attributedText = attributedString

}

Answer 5

Swift 已接受答案的 5.1

用法：

self.mytextView.attributedText = identifyTextContent(text_string)

函数：

func identifyTextContent(_ txtStr: String?) -> NSMutableAttributedString {

        let attributedString = NSMutableAttributedString(string: txtvwstr ?? "")
        let textAttachment = NSTextAttachment()
        var detector: NSDataDetector? = nil
        do {
            detector = try NSDataDetector(types: NSTextCheckingResult.CheckingType.link.rawValue)
        } catch {
        }
        detector?.enumerateMatches(in: txtvwstr ?? "", options: [], range: NSRange(location: 0, length: txtvwstr?.count ?? 0), using: { result, flags, stop in
            if let result = result {
                print("Values: \(result)")
            }
            if result?.resultType == .link {
                if let URL = result?.url {
                    print("matched: \(URL)")
                }

                //// You can use any library to download the image from detected url.*/

                var data: Data? = nil
                if let URL = result?.url {
                    do {
                    data = try Data(contentsOf: URL)
                    } catch {
                        print(error)
                    }
                }
                var img: UIImage? = nil
                if let data = data {
                    img = UIImage(data: data)

        //// Here You can adjust image size as well using CGSize(width, height).*/

                }
                textAttachment.image = img
                let attrStringWithImage = NSAttributedString(attachment: textAttachment)
                if let range = result?.range {
                    attributedString.replaceCharacters(in: range, with: attrStringWithImage)
                }
            }
        })

        return attributedString
    }