Objectif c - HTML to NSAttributedString

Question

J'ai écrit une fonction qui convertit le texte HTML en NSAttributedString. Cela fonctionne bien. Cependant, j'ai remarqué que certaines balises lorsqu'elles sont imbriquées dans une autre balise, leurs polices sont écrasées.

Voici mon code.

+(NSMutableAttributedString*) replaceHTMLTags : (NSString*) text : (NSString*) fontName : (CGFloat) fontSize 
{ 
    UIFont* font = [UIFont fontWithName:fontName size:fontSize]; 
    NSMutableParagraphStyle* paragraphStyle = [[NSMutableParagraphStyle alloc]init]; 
    paragraphStyle.lineBreakMode = NSLineBreakByWordWrapping; 
    paragraphStyle.alignment = NSTextAlignmentJustified; 

    text = [text stringByReplacingOccurrencesOfString:@"<br>" withString:@"\n"]; 
    NSMutableAttributedString* finalText = [[NSMutableAttributedString alloc]initWithString:text]; 

    [finalText setAttributes:@{NSFontAttributeName:font} range:NSMakeRange(0, [finalText string].length)]; 

    finalText = [self recurseFunc:finalText :@"" : font : paragraphStyle]; 
    return finalText; 
} 

+(NSMutableAttributedString*) recurseFunc : (NSMutableAttributedString*) text : (NSString*) tag : (UIFont*) font : (NSMutableParagraphStyle*) paragraphStyle 
{ 
    NSMutableAttributedString* finalText = text; 

    NSRange newOpenTagRange; 
    //RECURSE IF THERE ARE MORE TAGS 
    while((newOpenTagRange = [[text string] rangeOfString:@"<[^>]+>" options:NSRegularExpressionSearch]).location != NSNotFound) 
    { 
     NSString* openTagName = [[text string] substringWithRange:newOpenTagRange]; 
     NSString* closeTagName = [self getCloseTagName: openTagName]; 
     NSRange newCloseTagRange = [[text string ]rangeOfString:closeTagName]; 

     if(newCloseTagRange.location != NSNotFound) 
     { 
      NSString* textWithTags = [[text string] substringWithRange:NSMakeRange(newOpenTagRange.location, newCloseTagRange.location - newOpenTagRange.location + newCloseTagRange.length)]; 
      NSString* newPlainText = [textWithTags stringByReplacingOccurrencesOfString:openTagName withString:@""]; 
      newPlainText = [newPlainText stringByReplacingOccurrencesOfString:closeTagName withString:@""]; 

      NSMutableAttributedString* newText = [[NSMutableAttributedString alloc]initWithString:newPlainText attributes:@{NSFontAttributeName:font, NSParagraphStyleAttributeName:paragraphStyle}]; 

      newText = [self recurseFunc:newText :openTagName : font : paragraphStyle]; 
      [finalText replaceCharactersInRange:NSMakeRange(newOpenTagRange.location, newCloseTagRange.location - newOpenTagRange.location + newCloseTagRange.length) withAttributedString:newText]; 
     } 
     else 
     { 
      NSLog(@"Cannot find closing tag for tag %@", openTagName); 
     } 
    } 

    //FORMAT HTML TAGS 
    if([tag containsString:@"<p"]) 
    { 
     [finalText.mutableString appendString:@"\n\n"]; 
    } 

    else if ([tag isEqualToString:@"<i>"]) 
    { 
     UIFont* italicFont = [UIFont fontWithName:@"Arial-ItalicMT" size:DEFAULT_FONT_SIZE]; 
     [finalText addAttribute:NSFontAttributeName value:italicFont range:NSMakeRange(0, [finalText string].length)]; 
    } 
    else if ([tag isEqualToString:@"<b>"]) 
    { 
     UIFont* boldFont = [UIFont fontWithName:@"Arial-BoldMT" size:DEFAULT_FONT_SIZE]; 
     [finalText addAttribute:NSFontAttributeName value:boldFont range:NSMakeRange(0, [finalText string].length)]; 

    } 
    else if([tag isEqualToString:@"<ul>"]) 
    { 
     NSMutableParagraphStyle* tempStyle = [[NSMutableParagraphStyle alloc]init]; 
     tempStyle.headIndent = 30; 
     tempStyle.firstLineHeadIndent = 10; 
     tempStyle.lineBreakMode = NSLineBreakByWordWrapping; 
     tempStyle.alignment = NSTextAlignmentJustified; 

     NSString* temp = [[finalText string]stringByReplacingOccurrencesOfString:@"###" withString:@"•\t"]; 
     temp = [NSString stringWithFormat:@"\n%@", temp]; 
     [finalText setAttributedString:[[NSAttributedString alloc] initWithString:temp]]; 

     [finalText addAttribute:NSParagraphStyleAttributeName value:tempStyle range:NSMakeRange(0, [finalText string].length)]; 


    } 
    else if ([tag isEqualToString:@"<li>"]) 
    { 
     NSMutableAttributedString* tempAS = [[NSMutableAttributedString alloc]initWithString:@"###$$$\n"]; 
     NSRange r = [[tempAS string]rangeOfString:@"$$$"]; 
     [tempAS replaceCharactersInRange:r withAttributedString:finalText]; 
     [finalText setAttributedString:tempAS]; 

    } 
    return finalText; 
} 

Ceci fait exactement ce qu'il est censé faire, sauf pour un cas spécifique.

Par exemple, si j'ai un <b> ou une balise <i> dans une balise <ul><li>, le <b> ou <i> ne pas obtenir rendus.

Answer 1

Pour convertir HTML à NSAttributedString vous pouvez utiliser le code suivant:

[[NSAttributedString alloc] initWithData:[htmlString dataUsingEncoding:NSUTF8StringEncoding] 
          options:@{NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType, 
             NSCharacterEncodingDocumentAttribute: @(NSUTF8StringEncoding)} 
        documentAttributes:nil error:nil];