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UILabel 字体间距和行间距,计算高度,首行缩进, 多个UI

UILabel 字体间距和行间距,计算高度,首行缩进, 多个UI

作者: zombieEngineer | 来源:发表于2017-03-10 18:53 被阅读10817次

    开发中经常有要求一段文字要有显示隔开多大的行间距,字跟字之间也要有间距,首行还要有缩进,想想也是真苛刻。那么废话不多说,下面就给大家上方法。

    已封装好方法 可以加入到自己的Category

    1、UILabel 设置行间距 和 字间距

    52C5D9D2-039B-45C6-914A-CAE7465B1DF8.png
    /**
     *  给UILabel设置行间距和字间距
     *  @param space 间距
     *  @param text  内容
     *  @param font  字体
     *  @param zpace  字间距 --> @10 这样设置  默认的话设置 0 就ok
     */
    -(void)LW_setLineSpace:(CGFloat)space withLabelText:(NSString*)text withFont:(UIFont*)font withZspace:(NSNumber *)space
    {
        NSMutableParagraphStyle *paraStyle = [[NSMutableParagraphStyle alloc] init];
        paraStyle.lineBreakMode =NSLineBreakByCharWrapping;
        paraStyle.alignment =NSTextAlignmentLeft;
        paraStyle.lineSpacing = 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;
        if (zpace == 0) {
            dic =@{NSFontAttributeName:font,NSParagraphStyleAttributeName:paraStyle,NSKernAttributeName:@1.5f
                                 };
        }else {
            dic =@{NSFontAttributeName:font,NSParagraphStyleAttributeName:paraStyle,NSKernAttributeName:zpace
                   };
        }
        NSAttributedString *attributeStr = [[NSAttributedString alloc] initWithString:text attributes:dic];
        self.attributedText = attributeStr;
    }
    
    使用方法:[label1 LW_setLineSpace:5 withLabelText:@"我是字间距为5和行间距为5的字符串哦,我是字间距为5和行间距为5的字符串哦,我是字间距为5和行间距为5的字符串哦" withFont:[UIFont systemFontOfSize:17] withZspace:@5];
    

    那么行间距和字间距设置好之后,下面来看看计算一下设置间距后的UILabel 的高度

    2、UILabel 设置行间距 和 字间距 后的高度计算

    /**
     *  计算UILabel的高度(带有行间距的情况)
     *  @param text  内容
     *  @param font  字体
     *  @param width 宽度
     *  @return 高度
     *  @param zpace  字间距 --> @10 这样设置  默认的话设置 0 就ok
     */
    -(CGFloat)LW_getSpaceLabelHeight:(NSString*)text withFont:(UIFont*)font withWidth:(CGFloat)width withSpace:(CGFloat)space withZspace:(NSNumber *)zpace{
        NSMutableParagraphStyle *paraStyle = [[NSMutableParagraphStyle alloc] init];
        paraStyle.lineBreakMode =NSLineBreakByCharWrapping;
        paraStyle.alignment =NSTextAlignmentLeft;
        paraStyle.lineSpacing = space;
        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;
        if (zpace == 0) {
            dic =@{NSFontAttributeName:font,NSParagraphStyleAttributeName:paraStyle,NSKernAttributeName:@1.5f
                   };
        }else {
            dic =@{NSFontAttributeName:font,NSParagraphStyleAttributeName:paraStyle,NSKernAttributeName:zpace
                   };
        }
        
        CGSize size = [text boundingRectWithSize:CGSizeMake(width,MAXFLOAT) options:NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading attributes:dic context:nil].size;
        return size.height;
    }
    
    使用方法: CGFloat height = [label1 LW_getSpaceLabelHeight:@"我是字间距为5和行间距为5的字符串哦,我是字间距为5和行间距为5的字符串哦,我是字间距为5和行间距为5的字符串哦" withFont:[UIFont systemFontOfSize:17] withWidth:LWSCREEN_WIDTH-20 withSpace:5 withZspace:@5];
    

    3、接下来,再看看 UILabel 的首行缩进如何 缩进并且返回高度

    2C666B39-AE85-40C1-9918-41042694FE3C.png

    PS: 如果高度计算失败,可以提前设置下frame 不然可能会高度计算失败 label 要设置换行显示

    /**
     *  首行缩进 计算字符串高度
     *  @param text     内容
     *  @param indentationNum 要缩进几个字符
     *  @param alignment   对齐格式
     *  @param fontSize 字体大小
     *  @param width    宽度
     *  @return 返回高度
     */
    - (CGFloat)LW_getIndentationLabelHeight:(NSString *)text withStrIndentationNum:(int)indentationNum withNSTextAlignment:(NSTextAlignment )alignment withFontSize:(CGFloat)fontSize withWidth:(CGFloat)width
    {
        NSMutableParagraphStyle *paraStyle01 = [[NSMutableParagraphStyle alloc] init];
        paraStyle01.alignment = alignment;  //对齐
        paraStyle01.headIndent = 0.0f;//行首缩进
        //参数:(字体大小17号字乘以2,34f即首行空出两个字符)
        CGFloat emptylen = fontSize * indentationNum;
        paraStyle01.firstLineHeadIndent = emptylen;//首行缩进
        paraStyle01.tailIndent = 0.0f;//行尾缩进
        paraStyle01.lineSpacing = 2.0f;//行间距
        
        NSAttributedString *attrText = [[NSAttributedString alloc] initWithString:text attributes:@{NSParagraphStyleAttributeName:paraStyle01}];
        self.attributedText = attrText;
        CGFloat height = [self sizeThatFits:CGSizeMake([UIScreen mainScreen].bounds.size.width, CGFLOAT_MAX)].height;
        return height;
    }
    
    使用方法:CGFloat height = [label1 LW_getIndentationLabelHeight:@"首行缩进并且计算字符串高度,首行缩进并且计算字符串高度,首行缩进并且计算字符串高度,首行缩进并且计算字符串高度,首行缩进并且计算字符串高度,首行缩进并且计算字符串高度" withStrIndentationNum:2 withNSTextAlignment:NSTextAlignmentLeft withFontSize:17 withWidth:LWSCREEN_WIDTH-20];
    

    4、UILabel文字对齐

    B0569B40-1BCF-4C09-AE88-6E7BA07E023C.png
    - (void)LW_labelTextAlignment
    {
        NSMutableAttributedString *attributeString =  [[NSMutableAttributedString alloc] initWithString:self.text];
        CGSize attributeSize = [attributeString.string sizeWithAttributes:@{NSFontAttributeName:self.font}];
        CGSize adjustedSize = CGSizeMake(ceilf(attributeSize.width), ceilf(attributeSize.height));
        CGSize frame = self.frame.size;
        NSNumber *wordSpace = [NSNumber numberWithInt:((frame.width-adjustedSize.width)/(attributeString.length-1))];
        [attributeString addAttribute:NSKernAttributeName value:wordSpace range:NSMakeRange(0, attributeString.length-1)];
        self.attributedText = attributeString;
    }
    
    使用方法: [label LW_labelTextAlignment];
    

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