iOS - 给文字添加阴影

   NSString *str = @"分享";
  NSMutableAttributedString *attributedString=[[NSMutableAttributedString alloc]initWithString:str];
 NSShadow *shadow = [[NSShadow alloc]init];
 shadow.shadowBlurRadius = 1.0;
shadow.shadowOffset = CGSizeMake(1, 1);
 shadow.shadowColor = [UIColor blackColor];
 [attributedString addAttribute:NSShadowAttributeName value:shadow  range:NSMakeRange(0, attributedString.length)];
self.shareLabel.attributedText = attributedString;

摘自 ：https://www.jianshu.com/p/3c558d2fa250