iOS--UIButton图片在上，文字在下

- (void)setup
{
    // 调整图片
    self.imageView.xm_x = 0;
    self.imageView.xm_y = 0;
    self.imageView.xm_width = self.xm_width;
    self.imageView.xm_height = self.imageView.xm_width;
    
    // 调整文字
    self.titleLabel.xm_x = 0;
    self.titleLabel.xm_y = self.imageView.xm_height;
    self.titleLabel.xm_width = self.xm_width;
    self.titleLabel.xm_height = self.xm_height - self.titleLabel.xm_y;
}