使用换行符附加NSAttributedString会返回格式错误的属性字符串

Question

我正在使用NSMutableAttributedString并NSAttributedString以两种不同的字体大小显示标签文本.我的方法是:

NSMutableAttributedString *muAtrStr = [[NSMutableAttributedString alloc]initWithString:@"2"];
NSAttributedString *atrStr = [[NSAttributedString alloc]initWithString:@"days" attributes:@{NSFontAttributeName : [UIFont fontWithName:@"HelveticaNeue-Bold" size:8]}];
[muAtrStr appendAttributedString:atrStr];

它返回一个归因字符串,字体大小为12,字符大小为"2",字体大小为8.

但是,另一种情况是在2之后添加换行符.我使用以下代码:

NSMutableAttributedString *muAtrStr = [[NSMutableAttributedString alloc]initWithString:@"2"];
NSAttributedString *atrStr = [[NSAttributedString alloc]initWithString:@"\ndays" attributes:@{NSFontAttributeName : [UIFont fontWithName:@"HelveticaNeue-Bold" size:8]}];
[muAtrStr appendAttributedString:atrStr];

此时属性字符串应用全文的属性.我得到一个字体大小为8的"2 \ndays"的属性字符串.

Answer 1

试试下面的代码,它工作正常: -

NSMutableAttributedString *muAtrStr = [[NSMutableAttributedString alloc]initWithString:@"2"];
NSAttributedString *atrStr = [[NSAttributedString alloc]initWithString:@"\ndays" attributes:@{NSFontAttributeName : [UIFont fontWithName:@"HelveticaNeue-Bold" size:8]}];
[muAtrStr appendAttributedString:atrStr];
self.lbl.numberOfLines = 0;
[self.lbl setAttributedText:muAtrStr];

注意: - 同时将numberOfLines设置为0以允许任意数量的行

Answer 2

这适用于Swift:

let attributedText = NSAttributedString(string: "Happy \nDays")
label.numberOfLines = 0
label.lineBreakMode = .byWordWrapping
label.attributedText = attributedText