更改UITextView中的一個鏈接的屬性

Question

我有一個UITextView多個URL，我可以通過將dataDetectorTypes屬性設置爲UIDataDetectorTypeLink來激活它。然後我使用linkTextAttributes屬性來設置鏈接的顏色。現在，當用戶點擊其中一個鏈接（使用UITapGestureRecognizer）時，我只想更改該鏈接的顏色。如果我更改linkTextAttributes，所有鏈接都會改變顏色。

如何更改所點擊鏈接的顏色？

Answer 1

我想我解決了它，使用UITextView的子類調用，它具有rangeOfLink屬性。

首先，我UIViewControllerviewDidLoad:，我在handleTap添加

self.textView.dataDetectorTypes = UIDataDetectorTypeLink; // change for other link types 
self.textView.selectable = YES; 
self.textView.userInteractionEnabled = YES; 

UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc] initWithTarget: self action: @selector(handleTap:)]; 
tapGesture.cancelsTouchesInView = YES; 

[self.textView addGestureRecognizer: tapGesture]; 
[self.textView setNeedsDisplay]; // force a redraw so that drawRect is called 

然後，我這樣做：

self.linkTextAttributes = [NSDictionary dictionary]; 

NSError *error = nil; 
NSDataDetector *dataDetector = [NSDataDetector dataDetectorWithTypes: NSTextCheckingTypeLink error: &error]; // change for other link types 

if (!error && dataDetector) 
{ 
    NSArray* resultString = [dataDetector matchesInString: self.text 
               options: NSMatchingReportProgress 
               range: NSMakeRange(0, [self.text length])]; 
    if (resultString.count > 0) 
    { 
     NSMutableAttributedString *mas = [self.attributedText mutableCopy]; 

     for (NSTextCheckingResult* result in resultString) 
     { 
      if (result.resultType == NSTextCheckingTypeLink) 
      { 
       NSRange intersection = NSIntersectionRange(result.range, self.rangeOfLink); 

       if (intersection.length <= 0) // no match 
        [mas addAttribute: NSForegroundColorAttributeName 
           value: [UIColor blueColor] 
           range: self.rangeOfLink]; 
       else 
        [mas addAttribute: NSForegroundColorAttributeName 
           value: [UIColor redColor] 
           range: self.rangeOfLink]; 
      } 
     } 

     self.attributedText = mas; 
    } 
} 

[super drawRect: rect]; 

：

MyTextViewWithLink *aTextView = (IDTextViewWithLink *) recognizer.view; 

if (aTextView != self.textView) 
    return; 

if (recognizer.state == UIGestureRecognizerStateEnded) 
{ 
    CGPoint location = [recognizer locationInView: aTextView]; 

// this returns an NSTextCheckingResult if location is inside a link 
    NSTextCheckingResult *result = [self textCheckingResultAtPoint: location inTextView: aTextView]; 

    if (result) 
    { 
     aTextView.rangeOfLink = result.range; 
     [aTextView setNeedsDisplay]; // this will force the color change 

     // open url 
    } 
} 

最後我在UITextView子類中覆蓋drawRect

現在如果textView有多於一個鏈接，只有選定的鏈接會改變顏色。

Answer 2

如果這些網址是固定的。 例如： 我有以下網址：

• http://www.123.com
• http://www.456.com
• http://www.789.com

我會把他們的NSAttributedString 使用NSMutableAttributedString把它們結合在一起的所有

NSMutableAttributedString *urlsAttributedText = [[NSMutableAttributedString alloc]init]; 

NSAttributedString *url1 = [[NSAttributedString alloc]initWithString:NSLocalizedString(@"http://www.123.com\n", nil) attributes:@{NSForegroundColorAttributeName : [UIColor whiteColor], NSFontAttributeName : [UIFont systemFontOfSize:15.0f]}]; 

NSAttributedString *url2 = [[NSAttributedString alloc]initWithString:NSLocalizedString(@"http://www.456.com\n", nil) attributes:@{NSForegroundColorAttributeName : [UIColor greenColor], NSFontAttributeName : [UIFont systemFontOfSize:15.0f]}]; 

NSAttributedString *url3 = [[NSAttributedString alloc]initWithString:NSLocalizedString(@"http://www.789.com\n", nil) attributes:@{NSForegroundColorAttributeName : [UIColor redColor], NSFontAttributeName : [UIFont systemFontOfSize:15.0f]}]; 

[urlsAttributedText url1]; 
[urlsAttributedText appendAttributedString:url2]; 
[urlsAttributedText appendAttributedString:url3]; 

self.texView.attributedText = urlsAttributedText; 

乾杯！