NSTextAlignmentJustified到iOS上的UILable textAligment将崩溃

Question

我现在使用Xcode4.5和iOS6,iOS6更改了UILable的textAlignment,

label.textAlignment = NSTextAlignmentJustified;

使用ios6 SDK,代码将在iPhone 6.0 Simulator上崩溃.但不会在iOS 5.0 SDK的iPhone 5.0模拟器上崩溃.

iOS6支持NSTextAlignmentJustified,但为什么会崩溃？

Answer 1

编辑1:

使用NSAttributedString我们可以证明文本.

NSMutableParagraphStyle *paragraphStyles = [[NSMutableParagraphStyle alloc] init];
paragraphStyles.alignment                = NSTextAlignmentJustified;
paragraphStyles.firstLineHeadIndent      = 0.05;    // Very IMP

NSString *stringTojustify                = @"We are what our thoughts have made us; so take care about what you think. Words are secondary. Thoughts live; they travel far.";
NSDictionary *attributes                 = @{NSParagraphStyleAttributeName: paragraphStyles};
NSAttributedString *attributedString     = [[NSAttributedString alloc] initWithString:stringTojustify attributes:attributes];

self.lblQuote.attributedText             = attributedString;
self.lblQuote.numberOfLines              = 0;
[self.lblQuote sizeToFit];

UITextAlignmentJustify在iOS 6下不再可用的弃用.

在此SO链接中给出了所有可能的合理文本解决方案,还可以查看此页面和iOS6预发布文档.

Answer 2

我有种找到了一种方法,使标签Justifiy在iOS的7:我简单地设置NSBaselineOffsetAttributeName为0.

不知道为什么你需要在iOS 7上添加这个基线设置(它在iOS 6上运行正常).

NSMutableParagraphStyle *paragraph = [[NSMutableParagraphStyle alloc] init];
        paragraph.alignment = NSTextAlignmentJustified;

NSDictionary *attributes = @{ NSParagraphStyleAttributeName : paragraph,
                                        NSFontAttributeName : self.textLabel.font,
                              NSBaselineOffsetAttributeName : [NSNumber numberWithFloat:0] };

NSAttributedString *str = [[NSAttributedString alloc] initWithString:content 
                                                          attributes:attributes];

self.textLabel.attributedText = str;

希望有所帮助;)