ios 6與ios 5.1之間的核心文本差異？

Question

它似乎有在IOS 5.1和iOS 6的CoreText實現一定的差異，你可以從這兩個截圖看到：

IOS 6：

IOS 5：

首先，文本顏色沒有正確應用。看來在ios 5.1上kCTForegroundColorAttributeName要求你給它一個CGColor，而在iOS 6上，傳遞一個UIColor就足夠了。所以我通過更改我的代碼來解決問題：

[attributes setObject:(id)[color CGColor] 
       forKey:(NSString*)kCTForegroundColorAttributeName]; 

其次，段落間距稍微偏離。 「視力」和「根據」之間的距離是11px vs 25px（在屏幕截圖中測量）。在這兩種情況下，段落間距設置爲5：在控制檯的paragraphStyleRef

NSMutableData *styleSettingsArray = [NSMutableData data]; 
CGFloat spaceBefore,spaceAfter; 
... 
CTParagraphStyleSetting styleSettingB = {kCTParagraphStyleSpecifierParagraphSpacingBefore ,sizeof(CGFloat),&spaceBefore}; 
CTParagraphStyleSetting styleSettingA = {kCTParagraphStyleSpecifierParagraphSpacing   ,sizeof(CGFloat),&spaceAfter}; 
[styleSettingsArray appendBytes:&styleSettingB length:sizeof(styleSettingB)]; 
[styleSettingsArray appendBytes:&styleSettingA length:sizeof(styleSettingA)]; 
... 
if(styleSettingsArray.length > 0) 
{ 
    CTParagraphStyleRef paragraphStyleRef = CTParagraphStyleCreate([styleSettingsArray bytes], [styleSettingsArray length]/sizeof(CTParagraphStyleSetting)); 
    [dictionary setObject:(__bridge id)(paragraphStyleRef) forKey:(NSString*)kCTParagraphStyleAttributeName]; 
    CFRelease(paragraphStyleRef); 
} 

說明：

iOS 6: 
CTParagraphStyle: 
base writing direction = -1, alignment = 3, line break mode = 0, default tab interval = 0 
first line head indent = 0, head indent = 0, tail indent = 0 
line height multiple = 0, maximum line height = 0, minimum line height = 0 
line spacing adjustment = 0, paragraph spacing = 5, paragraph spacing before = 5 


iOS 5: 

CTParagraphStyle: 
writing direction = -1, alignment = 3, line break mode = 0, default tab interval = 0 
first line head indent = 0, head indent = 0, tail indent = 0 
line height multiple = 0, maximum line height = 0, minimum line height = 0 
line spacing adjustment = 0, paragraph spacing = 5, paragraph spacing before = 5 

這似乎同樣給​​我，所以我不知道是什麼問題。除了段落之間的間距之外，它們是相同的。

那麼我該如何解決這個問題？還有什麼我應該知道的事情可能會導致文本顯示不同？

編輯： 經過一番調查，它地調出該段造型的差異實際上是由它印有「\ r \ n」我的換行符造成的。將其改爲「\ n」解決了間距問題。

Answer 1

核心文本在iOS 6中進行了檢修。如果您擁有Apple開發人員帳戶，請通過觀看免費提供的WWDC 2012視頻來查看所有更改。

因此，現在在iOS 6中，不能使用任何低級核心文本屬性，如kCTForegroundColorAttributeName或kCTParagraphStyleAttributeName。

而是使用新的高級屬性集，如NSForegroundColorAttributeName & NSParagraphStyle。

所以，你的代碼將變爲：

/*Note that you have use the Foundation class 
    for the attribute value instead of it's Core-Foundation counterpart.*/ 

[attributes setObject:color 
      forKey:NSForegroundColorAttributeName]; 

CGFloat spaceBefore, spaceAfter; 

NSMutableParagraphStyle *mutableParagraphStyle = [NSMutableParagraphStyle defaultParagraphStyle]; 
mutableParagraphStyle.paragraphSpacing = spaceAfter; 
mutableParagraphStyle.paragraphSpacingBefore = spaceBefore; 

[attributes setObject:mutableParagraphStyle 
      forKey:NSParagraphStyleAttributeName]; 

您可以在文檔中的所有新屬性這裏： http://developer.apple.com/library/ios/#documentation/uikit/reference/NSAttributedString_UIKit_Additions/Reference/Reference.html