MarkdownAttributeLabel using XNGMarkdownParser

!MarkdownAttributedLabel

A TTTAttributedLabel convenience subclass that uses MMarkdown to parse markdown text.

LICENSE

The MIT License (MIT)

Copyright (c) 2015 MidaApp s.r.l.

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.

MarkdownAttributedLabel.h

//
//  MarkdownAttributedLabel.h
//
//  Created by Andrea Cremaschi on 20/03/14.
//  Copyright (c) 2014 midapp. All rights reserved.
//

#import <TTTAttributedLabel/TTTAttributedLabel.h>

@interface MarkdownAttributedLabel : TTTAttributedLabel

-(void)setMarkdownText: (NSString*)markdown;

@end

MarkdownAttributedLabel.m

//
//  MarkdownAttributedLabel.m
//
//  Created by Andrea Cremaschi on 20/03/14.
//  Copyright (c) 2014 midapp. All rights reserved.
//

#import "MarkdownAttributedLabel.h"
#import <XNGMarkdownParser/XNGMarkdownParser.h>
#import <XNGMarkdownParser/XNGMarkdownTokens.h>
#import <TTTAttributedLabel/TTTAttributedLabel.h>

@interface XNGMarkdownParser ()

- (void)consumeToken:(XNGMarkdownParserCode)token text:(char *)text;

@end

@interface MidaMarkdownParser : XNGMarkdownParser

@end

@interface NSAttributedString (FontSize)

- (NSAttributedString*) attributedStringWithFontSize:(CGFloat) fontSize;

@end

@implementation MarkdownAttributedLabel

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self)
    {
        [self commonInitLocal];
    }
    return self;
}

- (instancetype)initWithCoder:(NSCoder *)coder
{
    self = [super initWithCoder:coder];
    if (self)
    {
        [self commonInitLocal];
    }
    return self;
}

- (void)commonInitLocal
{// Initialization code
    self.enabledTextCheckingTypes = 0;
    self.dataDetectorTypes = 0;
    self.extendsLinkTouchArea = NO;
    
    NSMutableDictionary *linkAttributes = [self.linkAttributes mutableCopy];
    [linkAttributes removeObjectForKey:NSParagraphStyleAttributeName];
    self.linkAttributes = [linkAttributes copy];
    linkAttributes = [self.activeLinkAttributes mutableCopy];
    [linkAttributes removeObjectForKey:NSParagraphStyleAttributeName];
    self.activeLinkAttributes = [linkAttributes copy];
    linkAttributes = [self.inactiveLinkAttributes mutableCopy];
    [linkAttributes removeObjectForKey:NSParagraphStyleAttributeName];
    self.inactiveLinkAttributes = [linkAttributes copy];
}

- (void)setFont:(UIFont *)font
{
    BOOL sizeMatters = self.font.pointSize != font.pointSize;
    [super setFont:font];
    if (sizeMatters)
    {
        self.attributedText = [self.attributedText attributedStringWithFontSize:font.pointSize];
    }
}

- (NSParagraphStyle *)currentParagraphStyle
{
    TTTAttributedLabel *label = (TTTAttributedLabel*) self;
    NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
    paragraphStyle.alignment = label.textAlignment;
    paragraphStyle.lineSpacing = label.lineSpacing;
    paragraphStyle.minimumLineHeight = label.minimumLineHeight > 0 ? label.minimumLineHeight : label.font.lineHeight * label.lineHeightMultiple;
    paragraphStyle.maximumLineHeight = label.maximumLineHeight > 0 ? label.maximumLineHeight : label.font.lineHeight * label.lineHeightMultiple;
    paragraphStyle.lineHeightMultiple = label.lineHeightMultiple;
    paragraphStyle.firstLineHeadIndent = label.firstLineIndent;
    
    return paragraphStyle;
}


-(void)setMarkdownText: (NSString*)markdown {
    NSError *error;
    if (markdown == nil) {
        [self setText:nil];
        return;
    }
    
    XNGMarkdownParser *parser = [[MidaMarkdownParser alloc] init];
    NSAttributedString *attributedString = [parser attributedStringFromMarkdownString:markdown];
    
    
    TTTAttributedLabel *label = (TTTAttributedLabel*) self;
    
    NSParagraphStyle *paragraphStyle = [self currentParagraphStyle];
    NSMutableAttributedString *mutableAttributedString = [[NSMutableAttributedString alloc] initWithAttributedString:attributedString];
    [mutableAttributedString addAttributes:@{ NSParagraphStyleAttributeName : paragraphStyle } range:NSMakeRange(0, [mutableAttributedString length])];
    [label setText:[mutableAttributedString attributedStringWithFontSize:self.font.pointSize]];
}

- (void)setBounds:(CGRect)bounds
{
    [super setBounds:bounds];
    
    // If this is a multiline label, need to make sure
    // preferredMaxLayoutWidth always matches the frame width
    // (i.e. orientation change can mess this up)
    
    if (self.numberOfLines == 0 && bounds.size.width != self.preferredMaxLayoutWidth)
    {
        self.preferredMaxLayoutWidth = self.bounds.size.width;
        [self setNeedsUpdateConstraints];
    }
}

@end

@implementation MidaMarkdownParser

- (void)consumeToken:(XNGMarkdownParserCode)token text:(char *)text
{
    if (token == MARKDOWN_URL)
    {
        token = MARKDOWN_UNKNOWN;
    }
    [super consumeToken:token text:text];
}

@end

@implementation NSAttributedString (FontSize)

- (NSAttributedString*) attributedStringWithFontSize:(CGFloat) fontSize
{
    NSMutableAttributedString* attributedString = [self mutableCopy];
    
    {
        [attributedString beginEditing];
        
        [attributedString enumerateAttribute:NSFontAttributeName inRange:NSMakeRange(0, attributedString.length) options:0 usingBlock:^(id value, NSRange range, BOOL *stop)
         {
             
             UIFont* font = value;
             font = [font fontWithSize:fontSize];
             
             [attributedString removeAttribute:NSFontAttributeName range:range];
             [attributedString addAttribute:NSFontAttributeName value:font range:range];
         }];
        
        [attributedString endEditing];
    }
    
    return [attributedString copy];
}

@end

MarkdownAttributedLabel.podspec

Pod::Spec.new do |s|
 
  s.name         = "MarkdownAttributedLabel"
  s.version      = "0.0.3"
  s.summary      = "A TTTAttributedLabel convenience subclass that uses XNGMarkdownParser to parse markdown text."
 
  s.description  = <<-DESC
			
                   DESC
 
  s.homepage     = "https://gist.github.com/ec7f6569fbb612778031.git"
  
  s.license      = "MIT"
  
  s.author             = { "Andrea Cremaschi" => "[email protected]" }
  s.platform     = :ios, "5.0"
  s.source       = { :git => "https://gist.github.com/ec7f6569fbb612778031.git", :tag => "0.0.1" }
 
  s.source_files  = "*.{h,m}"
  s.exclude_files = "Classes/Exclude"
 
  s.public_header_files = "*.h"
 
  s.requires_arc = true
  
  s.dependency 'TTTAttributedLabel'
  s.dependency 'XNGMarkdownParser'
 
end