NSMutableParagraphStyle从UITextView中删除旧的NSMutableAttributedString

Question

我尝试在文本开头的UITextView中添加项目符号，但是当我使用此代码添加时，旧的attributionString和字体和大小都没有保存。

在此代码中：

 NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:currentTextViewEdit.text];

        NSMutableParagraphStyle *paragrahStyle = [[NSMutableParagraphStyle alloc] init];
        [paragrahStyle setParagraphSpacing:4];
        [paragrahStyle setParagraphSpacingBefore:3];
        [paragrahStyle setFirstLineHeadIndent:0.0f];  // First line is the one with bullet point
        [paragrahStyle setHeadIndent:10.5f];    // Set the indent for given bullet character and size font


        [attributedString addAttribute:NSParagraphStyleAttributeName value:paragrahStyle range:NSMakeRange(0, [currentTextViewEdit.text length])];


        currentTextViewEdit.attributedText = attributedString;

        currentTextViewEdit.text = [NSString stringWithFormat:@"1.%@",currentTextViewEdit.text];

我尝试添加一个NSMutableParagraphStyle但它删除了之前文本所具有的旧NSMutableAttributedString。