第2月第24天 coretext 行高

1.NSMutableAttributedString 行高

NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:labelText];
        NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
        
        [paragraphStyle setLineSpacing:LINESPACE];//调整行间距
        
        [attributedString addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0, [labelText length])];
        label.attributedText = attributedString;

http://blog.sina.com.cn/s/blog_9256a1210101ku7o.html

2.boundingRectWithSize 行高

#define UILABEL_LINE_SPACE 6
#define HEIGHT [ [ UIScreen mainScreen ] bounds ].size.height
//给UILabel设置行间距和字间距
-(void)setLabelSpace:(UILabel*)label withValue:(NSString*)str withFont:(UIFont*)font {
    NSMutableParagraphStyle *paraStyle = [[NSMutableParagraphStyle alloc] init];
    paraStyle.lineBreakMode = NSLineBreakByCharWrapping;
    paraStyle.alignment = NSTextAlignmentLeft;
    paraStyle.lineSpacing = UILABEL_LINE_SPACE; //设置行间距
    paraStyle.hyphenationFactor = 1.0;
    paraStyle.firstLineHeadIndent = 0.0;
    paraStyle.paragraphSpacingBefore = 0.0;
    paraStyle.headIndent = 0;
    paraStyle.tailIndent = 0;
    //设置字间距 NSKernAttributeName:@1.5f
    NSDictionary *dic = @{NSFontAttributeName:font, NSParagraphStyleAttributeName:paraStyle, NSKernAttributeName:@1.5f
};
    
    NSAttributedString *attributeStr = [[NSAttributedString alloc] initWithString:str attributes:dic];
    label.attributedText = attributeStr;
}

//计算UILabel的高度(带有行间距的情况)
-(CGFloat)getSpaceLabelHeight:(NSString*)str withFont:(UIFont*)font withWidth:(CGFloat)width {
    NSMutableParagraphStyle *paraStyle = [[NSMutableParagraphStyle alloc] init];
    paraStyle.lineBreakMode = NSLineBreakByCharWrapping;
    paraStyle.alignment = NSTextAlignmentLeft;
    paraStyle.lineSpacing = UILABEL_LINE_SPACE;
    paraStyle.hyphenationFactor = 1.0;
    paraStyle.firstLineHeadIndent = 0.0;
    paraStyle.paragraphSpacingBefore = 0.0;
    paraStyle.headIndent = 0;
    paraStyle.tailIndent = 0;
    NSDictionary *dic = @{NSFontAttributeName:font, NSParagraphStyleAttributeName:paraStyle, NSKernAttributeName:@1.5f
};
    
    CGSize size = [str boundingRectWithSize:CGSizeMake(width, HEIGHT) options:NSStringDrawingUsesLineFragmentOrigin attributes:dic context:nil].size;
    return size.height;
}

http://blog.csdn.net/luco2008/article/details/50977718

3.CTFramesetterSuggestFrameSizeWithConstraints 行高

 

1)CFMutableAttributedStringRef/NSAttributedString

2)CTParagraphStyleRef/NSMutableParagraphStyle

 

NSString  *text = @"This
is
some
multi-line
sample
text."
UIFont    *uiFont = [UIFont fontWithName:@"Helvetica" size:17.0];
CTFontRef ctFont = CTFontCreateWithName((CFStringRef) uiFont.fontName, uiFont.pointSize, NULL);

//  When you create an attributed string the default paragraph style has a leading 
//  of 0.0. Create a paragraph style that will set the line adjustment equal to
//  the leading value of the font.
CGFloat leading = uiFont.lineHeight - uiFont.ascender + uiFont.descender;
CTParagraphStyleSetting paragraphSettings[1] = { kCTParagraphStyleSpecifierLineSpacingAdjustment, sizeof (CGFloat), &leading };

CTParagraphStyleRef  paragraphStyle = CTParagraphStyleCreate(paragraphSettings, 1);
CFRange textRange = CFRangeMake(0, text.length);

//  Create an empty mutable string big enough to hold our test
CFMutableAttributedStringRef string = CFAttributedStringCreateMutable(kCFAllocatorDefault, text.length);

//  Inject our text into it
CFAttributedStringReplaceString(string, CFRangeMake(0, 0), (CFStringRef) text);

//  Apply our font and line spacing attributes over the span
CFAttributedStringSetAttribute(string, textRange, kCTFontAttributeName, ctFont);
CFAttributedStringSetAttribute(string, textRange, kCTParagraphStyleAttributeName, paragraphStyle);

CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString(string);
CFRange fitRange;

CGSize frameSize = CTFramesetterSuggestFrameSizeWithConstraints(framesetter, textRange, NULL, bounds, &fitRange);

CFRelease(framesetter);
CFRelease(string);

http://stackoverflow.com/questions/3374591/ctframesettersuggestframesizewithconstraints-sometimes-returns-incorrect-size

http://blog.sina.com.cn/s/blog_6308b98c0101byh9.html

4.yytext

http://www.cnblogs.com/lujianwenance/p/5716804.html

5.nsattributedstring 转nsstring

6.UILabel和Scrollview结合用，label高度自适应

https://my.oschina.net/langzhouzhou1/blog/648748

7.计算高度

- (CGFloat)boundingRectWithSize:(CGFloat)width
           withAttributedString:(NSMutableAttributedString *)attrt {
  CGFloat height = 0;
  NSStringDrawingOptions options =
      NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading;
  CGRect rect = [attrt boundingRectWithSize:CGSizeMake(width, CGFLOAT_MAX)
                                    options:options
                                    context:nil];
  height = ceilf(rect.size.height);
  return height;
}

- (CGFloat)stringWidthWithSize:(CGSize)size font:(UIFont *)font {
  CGFloat width;

  if ([PAUntils isAtLeastIOS_7_0]) {
    CGRect rect =
        [self boundingRectWithSize:size
                           options:NSStringDrawingUsesLineFragmentOrigin
                        attributes:@{
                          NSFontAttributeName : font
                        }
                           context:nil];
    width = rect.size.width;
  } else {
    CGSize strSize = [self sizeWithFont:font constrainedToSize:size];
    width = strSize.width;
  }

  return width;
}