问屏幕上垂直和水平的离子中心文本的问题？

- (NSMutableAttributedString *)styleSalePriceLabel:(NSString *)salePrice withFont:(UIFont *)font
{
    if ([salePrice rangeOfString:@"."].location == NSNotFound) {
        return [[NSMutableAttributedString alloc] initWithString:salePrice];
    } else {
        NSRange range = [salePrice rangeOfString:@"."];
        range.length = (salePrice.length - range.location);
        NSMutableAttributedString *stylizedPriceLabel = [[NSMutableAttributedString alloc] initWithString:salePrice];
        UIFont *smallFont = [UIFont fontWithName:font.fontName size:(font.pointSize / 2)];
        NSNumber *offsetAmount = @(font.capHeight - smallFont.capHeight);
        [stylizedPriceLabel addAttribute:NSFontAttributeName value:smallFont range:range];
        [stylizedPriceLabel addAttribute:NSBaselineOffsetAttributeName value:offsetAmount range:range];
        return stylizedPriceLabel;
    }
}

//Make sure the labels hug their contents
[self.bigTextLabel sizeToFit];
[self.smallTextLabel sizeToFit];

//Figure out the "blank" space above normal character height for the big text
UIFont *bigFont = self.bigTextLabel.font;
CGFloat bigAscenderSpace = (bigFont.ascender - bigFont.capHeight);

//Move the small text down by that ammount
CGFloat smallTextOrigin = CGRectGetMinY(self.bigTextLabel.frame) + bigAscenderSpace;

//Figure out the "blank" space above normal character height for the little text
UIFont *smallFont = self.smallTextLabel.font;
CGFloat smallAscenderSpace = smallFont.ascender - smallFont.capHeight;

//Move the small text back up by that ammount
smallTextOrigin -= smallAscenderSpace;

//Actually assign the frames
CGRect smallTextFrame = self.smallTextLabel.frame;
smallTextFrame.origin.y = smallTextOrigin;
self.smallTextLabel.frame = smallTextFrame;