UIlabel设置行间距,字间距

2017-04-10

在iOS开发中经常会用到UIlabel来展示一些文字性的内容，但是默认的文字排版会觉得有些挤，为了更美观也更易于阅读我们可以通过某些方法将UIlabel的行间距和字间距按照需要调节。
代码如下：

- (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;
}