TTTAttributedLabel


A drop-in replacement for UILabel that supports attributes, data detectors, links, and more.

Link : https://github.com/arun-perk/TTTAttributedLabel

TTTAttributedLabel is a drop-in replacement for UILabel providing a simple way to performantly render attributed strings. As a bonus, it also supports link embedding, both automatically with NSTextCheckingTypes and manually by specifying a range for a URL, address, phone number, event, or transit information.
Even though UILabel received support for NSAttributedString in iOS 6, TTTAttributedLabel has several unique features:
  • Automatic data detection
  • Manual link embedding
  • Label style inheritance for attributed strings
  • Custom styling for links within the label
  • Long-press gestures in addition to tap gestures for links
It also includes advanced paragraph style properties:
  • attributedTruncationToken
  • firstLineIndent
  • highlightedShadowRadius
  • highlightedShadowOffset
  • highlightedShadowColor
  • lineHeightMultiple
  • lineSpacing
  • minimumLineHeight
  • maximumLineHeight
  • shadowRadius
  • textInsets
  • verticalAlignment

Requirements

  • iOS 8+ / tvOS 9+
  • Xcode 7+

Accessibility

As of version 1.10.0, TTTAttributedLabel supports VoiceOver through the UIAccessibilityElement protocol. Each link can be individually selected, with an accessibilityLabel equal to its string value, and a corresponding accessibilityValue for URL, phone number, and date links. Developers who wish to change this behavior or provide custom values should create a subclass and override accessibilityElements.

Communication

  • If you need help, use Stack Overflow. (Tag tttattributedlabel)
  • If you'd like to ask a general question, use Stack Overflow.
  • If you found a bug, open an issue.
  • If you have a feature request, open an issue.
  • If you want to contribute, submit a pull request.

Installation

CocoaPods is the recommended method of installing TTTAttributedLabel. Simply add the following line to your Podfile:
# Podfile

pod 'TTTAttributedLabel'

Usage

TTTAttributedLabel can display both plain and attributed text: just pass an NSString or NSAttributedString to the setText: setter. Never assign to the attributedText property.
// NSAttributedString

TTTAttributedLabel *attributedLabel = [[TTTAttributedLabel alloc] initWithFrame:CGRectZero];

NSAttributedString *attString = [[NSAttributedString alloc] initWithString:@"Tom Bombadil"
                                                                attributes:@{
        (id)kCTForegroundColorAttributeName : (id)[UIColor redColor].CGColor,
        NSFontAttributeName : [UIFont boldSystemFontOfSize:16],
        NSKernAttributeName : [NSNull null],
        (id)kTTTBackgroundFillColorAttributeName : (id)[UIColor greenColor].CGColor
}];

// The attributed string is directly set, without inheriting any other text
// properties of the label.
attributedLabel.text = attString;
// NSString

TTTAttributedLabel *label = [[TTTAttributedLabel alloc] initWithFrame:CGRectZero];
label.font = [UIFont systemFontOfSize:14];
label.textColor = [UIColor darkGrayColor];
label.lineBreakMode = NSLineBreakByWordWrapping;
label.numberOfLines = 0;

// If you're using a simple `NSString` for your text,
// assign to the `text` property last so it can inherit other label properties.
NSString *text = @"Lorem ipsum dolor sit amet";
[label setText:text afterInheritingLabelAttributesAndConfiguringWithBlock:^ NSMutableAttributedString *(NSMutableAttributedString *mutableAttributedString) {
  NSRange boldRange = [[mutableAttributedString string] rangeOfString:@"ipsum dolor" options:NSCaseInsensitiveSearch];
  NSRange strikeRange = [[mutableAttributedString string] rangeOfString:@"sit amet" options:NSCaseInsensitiveSearch];

  // Core Text APIs use C functions without a direct bridge to UIFont. See Apple's "Core Text Programming Guide" to learn how to configure string attributes.
  UIFont *boldSystemFont = [UIFont boldSystemFontOfSize:14];
  CTFontRef font = CTFontCreateWithName((__bridge CFStringRef)boldSystemFont.fontName, boldSystemFont.pointSize, NULL);
  if (font) {
    [mutableAttributedString addAttribute:(NSString *)kCTFontAttributeName value:(__bridge id)font range:boldRange];
    [mutableAttributedString addAttribute:kTTTStrikeOutAttributeName value:@YES range:strikeRange];
    CFRelease(font);
  }

  return mutableAttributedString;
}];
First, we create and configure the label, the same way you would instantiate UILabel. Any text properties that are set on the label are inherited as the base attributes when using the -setText:afterInheritingLabelAttributesAndConfiguringWithBlock: method. In this example, the substring "ipsum dolar", would appear in bold, such that the label would read "Lorem ipsum dolar sit amet", in size 14 Helvetica, with a dark gray color.

IBDesignable

TTTAttributedLabel includes IBInspectable and IB_DESIGNABLE annotations to enable configuring the label inside Interface Builder. However, if you see these warnings when building...
IB Designables: Failed to update auto layout status: Failed to load designables from path (null)
IB Designables: Failed to render instance of TTTAttributedLabel: Failed to load designables from path (null)
...then you are likely using TTTAttributedLabel as a static library, which does not support IB annotations. Some workarounds include:
  • Install TTTAttributedLabel as a dynamic framework using CocoaPods with use_frameworks! in your Podfile, or with Carthage
  • Install TTTAttributedLabel by dragging its source files to your project

Links and Data Detection

In addition to supporting rich text, TTTAttributedLabel can automatically detect links for dates, addresses, URLs, phone numbers, transit information, and allows you to embed your own links.
label.enabledTextCheckingTypes = NSTextCheckingTypeLink; // Automatically detect links when the label text is subsequently changed
label.delegate = self; // Delegate methods are called when the user taps on a link (see `TTTAttributedLabelDelegate` protocol)

label.text = @"Fork me on GitHub! (https://github.com/mattt/TTTAttributedLabel/)"; // Repository URL will be automatically detected and linked

NSRange range = [label.text rangeOfString:@"me"];
[label addLinkToURL:[NSURL URLWithString:@"http://github.com/mattt/"] withRange:range]; // Embedding a custom link in a substring

Demo

pod try TTTAttributedLabel
...or clone this repo and build and run/test the Espressos project in Xcode to see TTTAttributedLabel in action. If you don't have CocoaPods installed, grab it with [sudo] gem install cocoapods.



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