NSAttributedString绘制按钮上图下字体

/// 使用图像和文本生成上下排列的属性文本
///
/// @param image      图像
/// @param imageWH    图像宽高
/// @param title      标题文字
/// @param fontSize   标题字体大小
/// @param titleColor 标题颜色
/// @param spacing    图像和标题间距
///
/// @return 属性文本
+ (instancetype)imageTextWithImage:(UIImage *)image imageWH:(CGFloat)imageWH title:(NSString *)title fontSize:(CGFloat)fontSize titleColor:(UIColor *)titleColor spacing:(CGFloat)spacing {
// 文本字典
NSDictionary *titleDict = @{NSFontAttributeName : [UIFont systemFontOfSize:fontSize],
NSForegroundColorAttributeName : titleColor};
NSDictionary *spacingDict = @{NSFontAttributeName : [UIFont systemFontOfSize:spacing]};

// 图片文本
NSTextAttachment *attachment = [[NSTextAttachment alloc] init];
attachment.image = image;
attachment.bounds = CGRectMake(0, 0, imageWH, imageWH);
NSAttributedString *imageText = [NSAttributedString attributedStringWithAttachment:attachment];

// 换行文本
NSAttributedString *lineText = [[NSAttributedString alloc] initWithString:@"\n\n" attributes:spacingDict];

// 按钮文字
NSAttributedString *text = [[NSAttributedString alloc] initWithString:title attributes:titleDict];

// 合并文字
NSMutableAttributedString *attM = [[NSMutableAttributedString alloc] initWithAttributedString:imageText];
[attM appendAttributedString:lineText];
[attM appendAttributedString:text];

return attM.copy;
}