Question

我正在尝试将属性字符串设置为iOS 6中的UITextView。问题是，如果我尝试在属性字符串上设置font属性，则会忽略行间距。但是，如果我没有设置字体，并且使用了默认字体，则行间距可以工作。

NSString *string = @" Hello \n world";
attrString = [[NSMutableAttributedString alloc] initWithString:string];
NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle defaultParagraphStyle] mutableCopy];

paragraphStyle.minimumLineHeight = 50;
// setting the font below makes line spacing become ignored
[attrString addAttribute:NSFontAttributeName value:[UIFont boldSystemFontOfSize:20] range:NSMakeRange(0, string.length)];
[attrString addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0, string.length)];

mainTextView.attributedText = attrString;

知道发生了什么事吗？

Answer 1

Attributed String Programming Guide:

UIFont *font = [UIFont fontWithName:@"Palatino-Roman" size:14.0];
NSDictionary *attrsDictionary = [NSDictionary dictionaryWithObject:font
                                forKey:NSFontAttributeName];
NSAttributedString *attrString = [[NSAttributedString alloc] initWithString:@"strigil" attributes:attrsDictionary];

更新：我尝试在自己的应用中使用addAttribute:方法，但它似乎无法在iOS 6模拟器上运行：

NSLog(@"%@", textView.attributedText);

日志似乎显示正确添加的属性，但iOS模拟器上的视图未显示属性。

Answer 2

我发现了你的问题，因为我还在与NSAttributedString战斗。对我来说，beginEditing和endEditing方法就像Changing an Attributed String中所说的那样。除此之外，lineSpacing在paragraphStyle上设置为setLineSpacing。

因此，您可能需要尝试将代码更改为：

NSString *string = @" Hello \n world";
attrString = [[NSMutableAttributedString alloc] initWithString:string];
NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle defaultParagraphStyle] mutableCopy];

[paragraphStyle setLineSpacing:20]  // Or whatever (positive) value you like...    
[attrSting beginEditing];

[attrString addAttribute:NSFontAttributeName value:[UIFont boldSystemFontOfSize:20] range:NSMakeRange(0, string.length)];
[attrString addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0, string.length)];

[attrString endEditing];

mainTextView.attributedText = attrString;

虽然没有测试这个确切的代码，顺便说一句，但我看起来几乎一样。

编辑：

与此同时，我已对其进行了测试，如果我错了，请更正我，- beginEditing和- endEditing来电似乎非常重要。

Answer 3

iOS 6中存在一个错误，导致在设置字体时忽略行高。请参阅NSParagraphStyle line spacing ignored的答案以及Radar: UITextView Ignores Minimum/Maximum Line Height in Attributed String处的较长错误分析。

Answer 4

//For proper line spacing

NSString *text1 = @"Hello";
NSString *text2 = @"\nWorld";
UIFont *text1Font = [UIFont fontWithName:@"HelveticaNeue-Medium" size:10];
NSMutableAttributedString *attributedString1 =
[[NSMutableAttributedString alloc] initWithString:text1 attributes:@{ NSFontAttributeName : text1Font }];
NSMutableParagraphStyle *paragraphStyle1 = [[NSMutableParagraphStyle alloc] init];
[paragraphStyle1 setAlignment:NSTextAlignmentCenter];
[paragraphStyle1 setLineSpacing:4];
[attributedString1 addAttribute:NSParagraphStyleAttributeName value:paragraphStyle1 range:NSMakeRange(0, [attributedString1 length])];

UIFont *text2Font = [UIFont fontWithName:@"HelveticaNeue-Medium" size:16];
NSMutableAttributedString *attributedString2 =
[[NSMutableAttributedString alloc] initWithString:text2 attributes:@{NSFontAttributeName : text2Font }];
NSMutableParagraphStyle *paragraphStyle2 = [[NSMutableParagraphStyle alloc] init];
[paragraphStyle2 setLineSpacing:4];
[paragraphStyle2 setAlignment:NSTextAlignmentCenter];
[attributedString2 addAttribute:NSParagraphStyleAttributeName value:paragraphStyle2 range:NSMakeRange(0, [attributedString2 length])];

[attributedString1 appendAttributedString:attributedString2];

Answer 5

您可以使用this example并按以下方式更改其实现：

[self enumerateAttribute:NSParagraphStyleAttributeName
                 inRange:NSMakeRange(0, self.length)
                 options:0
              usingBlock:^(id  _Nullable value, NSRange range, BOOL * _Nonnull stop) {
                  NSMutableParagraphStyle *paragraphStyle = [[NSParagraphStyle defaultParagraphStyle] mutableCopy];

                  //add your specific settings for paragraph
                  //...
                  //...

                  [self removeAttribute:NSParagraphStyleAttributeName range:range];
                  [self addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:range];
              }];

在UITextView上设置NSAttributedString上的字体忽略行间距

5 个答案:

编辑：