ios图文混排

NSMutableAttributedString *str=[[NSMutableAttributedString alloc] initWithString:@"fdsahfjdsafkdhafjkhadjksfhjk" attributes:nil];

NSTextAttachment *attachment=[[NSTextAttachment alloc] initWithData:nil ofType:nil];
UIImage *img=[UIImage imageNamed:@"xxx.png"];
attachment.image=img;
attachment.bounds=CGRectMake(0, -10, 20, 20);
NSAttributedString *text=[NSAttributedString attributedStringWithAttachment:attachment];

[str insertAttributedString:text atIndex:2];
self.textView.attributedText=str;