How to open a ViewController on click of hyperlink on UILable in Objective C-CodePudding

I have to open ViewController through hyperlink on UILable. I have refered this but it worked half for me. I can not use UITextView according to my project requirement.

Below code creates hyperlink on UILable and detect touch on hyper link but we have to open ViewController instead of url.

Declaration

@property (weak, nonatomic) IBOutlet UILabel *label;
NSLayoutManager *layoutManager;
NSTextContainer *textContainer;
NSTextStorage *textStorage;

// To create hyperlink on UILable.

NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:@"String with a link" attributes:nil];
NSRange linkRange = NSMakeRange(14, 4);
NSDictionary *linkAttributes = @{ NSForegroundColorAttributeName : [UIColor colorWithRed:0.05 green:0.4 blue:0.65 alpha:1.0],
                                  NSUnderlineStyleAttributeName : @(NSUnderlineStyleSingle) };
[attributedString setAttributes:linkAttributes range:linkRange];
_label.attributedText = attributedString;

// To detect touches on this Hyperlink.

_label.userInteractionEnabled = YES;
[_label addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleTapOnLabel:)]];

To Find out tap was on link, not on any other portion of the label.

// Create instances of NSLayoutManager, NSTextContainer and NSTextStorage

layoutManager = [[NSLayoutManager alloc] init];
textContainer = [[NSTextContainer alloc] initWithSize:CGSizeZero];
textStorage = [[NSTextStorage alloc] initWithAttributedString:attributedString];

// Configure layoutManager, textStorage and textContainer

[layoutManager addTextContainer:textContainer];

[textStorage addLayoutManager:layoutManager];

textContainer.lineFragmentPadding = 0.0;
textContainer.lineBreakMode = _label.lineBreakMode;
textContainer.maximumNumberOfLines =_label.numberOfLines;

// each time the label changes its frame, update textContainer's size:

- (void)viewDidLayoutSubviews
{
    [super viewDidLayoutSubviews];
    textContainer.size = self.label.bounds.size;
}

// detect whether the tap was exactly on the link:

- (void)handleTapOnLabel:(UITapGestureRecognizer *)tapGesture
{
    CGPoint locationOfTouchInLabel = [tapGesture locationInView:tapGesture.view];
    CGSize labelSize = tapGesture.view.bounds.size;
    CGRect textBoundingBox = [layoutManager usedRectForTextContainer:textContainer];
    CGPoint textContainerOffset = CGPointMake((labelSize.width - textBoundingBox.size.width) * 0.5 - textBoundingBox.origin.x,
                                              (labelSize.height - textBoundingBox.size.height) * 0.5 - textBoundingBox.origin.y);
    CGPoint locationOfTouchInTextContainer = CGPointMake(locationOfTouchInLabel.x - textContainerOffset.x,
                                                         locationOfTouchInLabel.y - textContainerOffset.y);
    NSInteger indexOfCharacter = [layoutManager characterIndexForPoint:locationOfTouchInTextContainer
                                                       inTextContainer:textContainer
                              fractionOfDistanceBetweenInsertionPoints:nil];
    NSRange linkRange = NSMakeRange(14, 4);
    if (NSLocationInRange(indexOfCharacter, linkRange)) {
        // Open an URL, or handle the tap on the link in any other way
        [[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"https://stackoverflow.com/"]];
    }
}

// using this function to present newViewController

-(void)navigateToTATViewController{
    TATViewController *tatVC = [[self getStoryboardWithStoryboardType: kListingStoryboard] instantiateViewControllerWithIdentifier: @"TATViewControllerID"];
    [self.navigationController presentViewController: tatVC animated:true completion:nil];
}

CodePudding user response：

So basically you need to update the line:

[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"https://stackoverflow.com/"]];

and replace it with [self navigateToTATViewController];