检测 NSAttributedString 中的链接点击

Question

我正在使用 drawInRect: 动态构建视图并在其上打印属性文本。某些文本可能包含网络链接。如何检测 Web 链接上的点击，以便在 UIWebView 中加载链接？我没有使用 UILabel、UITextView 或 UITextField 来显示文本，因为文本包含文本和图像的混合。

这是绘制文本的 UIView 子类的 drawRect 中的一些代码。

//draw the text

    NSMutableAttributedString *attString = [[NSMutableAttributedString alloc] initWithString:self.message.text];

    [attString beginEditing];

    NSArray *arrString = [attString.string componentsSeparatedByString:@" "];
    for (NSString *str in arrString)
    {
        if ([str rangeOfString:@"http://" options:NSCaseInsensitiveSearch].location != NSNotFound ||
            [str rangeOfString:@".com"    options:NSCaseInsensitiveSearch].location != NSNotFound ||
            [str rangeOfString:@".gov"    options:NSCaseInsensitiveSearch].location != NSNotFound ||
            [str rangeOfString:@".org"    options:NSCaseInsensitiveSearch].location != NSNotFound ||
            [str rangeOfString:@".edu"    options:NSCaseInsensitiveSearch].location != NSNotFound ||
            [str rangeOfString:@".net"    options:NSCaseInsensitiveSearch].location != NSNotFound ||
            [str rangeOfString:@".xxx"    options:NSCaseInsensitiveSearch].location != NSNotFound)
        {
            NSRange rng = [attString.string rangeOfString:str];

            NSString *url;

            if ([str rangeOfString:@"http://"  options:NSCaseInsensitiveSearch].location == NSNotFound &&
                [str rangeOfString:@"https://" options:NSCaseInsensitiveSearch].location == NSNotFound)
            {
                url = [NSString stringWithFormat:@"http://%@", str];
            }
            else
            {
                url = str;
            }

            [attString addAttribute:NSLinkAttributeName value:[NSURL URLWithString:url] range:rng];
        }
    }

    [attString endEditing];

    CGSize theSize;
    theSize = [attString.string sizeWithFont:[UIFont systemFontOfSize:14.0f] constrainedToSize:CGSizeMake(CHAT_TEXT_WIDTH, FLT_MAX) lineBreakMode:NSLineBreakByWordWrapping];
    [[UIColor blackColor] set];
    CGRect textRect = CGRectMake(0, 0, theSize.width, theSize.height);
    textRect.origin.x += 10;
    textRect.origin.y += 10;

    if (self.type == MESSAGE_BOX_RECEIVE) {
        textRect.origin.x += ARROW_WIDTH;
    }

    [attString drawInRect:textRect];

感谢您的帮助...

Answer 1

您要做的是使用 TextKit（在 iOS 7 中引入）绘制文本。这也允许您通过 TextKit 来解释点击。

这是一个可下载的示例项目，我在其中显示了一个单词列表并检测用户点击了哪个单词（我什至会暂时突出显示该单词）：

https://github.com/mattneub/Programming-iOS-Book-Examples/blob/master/bk2ch10p543drawingWithTextKit/ch23p815attributedStringDrawing3/StyledText.swift