NSAttributedString添加文本对齐方式

Question

如何将文本对齐属性添加到NSAttributedString以使文本居中？

编辑:我做错了什么？它似乎没有改变对齐方式.

CTParagraphStyleSetting setting;
setting.spec = kCTParagraphStyleSpecifierAlignment;
setting.valueSize = kCTCenterTextAlignment;

CTParagraphStyleSetting settings[1] = {
    {kCTParagraphStyleSpecifierAlignment, sizeof(CGFloat), &setting},           
};

CTParagraphStyleRef paragraph = CTParagraphStyleCreate(settings, sizeof(setting));

NSMutableAttributedString *mutableAttributed = [[NSMutableAttributedString alloc] initWithAttributedString:self.attributedString];
[mutableAttributed addAttributes:[NSDictionary dictionaryWithObjectsAndKeys:(NSObject*)paragraph ,(NSString*) kCTParagraphStyleAttributeName, nil] range:_selectedRange];

Answer 1

 NSMutableParagraphStyle *paragraphStyle = NSMutableParagraphStyle.new;
 paragraphStyle.alignment                = NSTextAlignmentCenter;

 NSAttributedString *attributedString   = 
[NSAttributedString.alloc initWithString:@"someText" 
                              attributes:
         @{NSParagraphStyleAttributeName:paragraphStyle}];

Answer 2

我正在搜索相同的问题,并能够以这种方式将文本居中对齐NSAttributedString:

NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc]init] ;
[paragraphStyle setAlignment:NSTextAlignmentCenter];

NSMutableAttributedString *attribString = [[NSMutableAttributedString alloc]initWithString:string];
[attribString addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0, [string length])];

Answer 3

Swift 3.0+

let titleParagraphStyle = NSMutableParagraphStyle()
titleParagraphStyle.alignment = .center

let titleFont = UIFont.preferredFont(forTextStyle: UIFontTextStyle.headline)
let title = NSMutableAttributedString(string: "You Are Registered", 
    attributes: [.font: titleFont,    
    .foregroundColor: UIColor.red, 
    .paragraphStyle: titleParagraphStyle])

(原答案如下)

Swift 2.0+

let titleParagraphStyle = NSMutableParagraphStyle()
titleParagraphStyle.alignment = .center

let titleFont = UIFont.preferredFont(forTextStyle: UIFontTextStyle.headline)
let title = NSMutableAttributedString(string: "You Are Registered", 
    attributes: [NSFontAttributeName:titleFont,    
    NSForegroundColorAttributeName:UIColor.red, 
    NSParagraphStyleAttributeName: titleParagraphStyle])

Answer 4

由于NSAttributedString主要用于iOS上的Core Text,您必须使用CTParagraphStyle而不是NSParagraphStyle.没有可变的变体.

例如:

CTTextAlignment alignment = kCTCenterTextAlignment;

CTParagraphStyleSetting alignmentSetting;
alignmentSetting.spec = kCTParagraphStyleSpecifierAlignment;
alignmentSetting.valueSize = sizeof(CTTextAlignment);
alignmentSetting.value = &alignment;

CTParagraphStyleSetting settings[1] = {alignmentSetting};

size_t settingsCount = 1;
CTParagraphStyleRef paragraphRef = CTParagraphStyleCreate(settings, settingsCount);
NSDictionary *attributes = @{(__bridge id)kCTParagraphStyleAttributeName : (__bridge id)paragraphRef};
NSAttributedString *attributedString = [[NSAttributedString alloc] initWithString:@"Hello World" attributes:attributes];

Answer 5

斯威夫特4回答:

// Define paragraph style - you got to pass it along to NSAttributedString constructor
let paragraphStyle = NSMutableParagraphStyle()
paragraphStyle.alignment = .center

// Define attributed string attributes
let attributes = [NSAttributedStringKey.paragraphStyle: paragraphStyle]

let attributedString = NSAttributedString(string:"Test", attributes: attributes)