在NSString或nsmutablestring中不可能有多种颜色。我听说过一点NSAttributedString,它是在iPad SDK 3.2(或大约3.2)中引入的,并且在iPhone SDK 4.0 beta版中可用。

我想要一根有三种颜色的绳子。

我不使用3个独立的NSString的原因,是因为三个NSAttributedString子字符串的长度经常改变,所以我宁愿,不使用任何计算重新定位3个独立的NSString对象。

如果使用NSAttributedString是可能的,我怎么做以下-(如果不可能使用NSAttributedString,你会怎么做):

编辑: 记住,@"first", @"second"和@"third"随时会被其他字符串替换。所以使用硬编码的NSRange值是行不通的。


当前回答

我认为,使用正则表达式来查找应用属性的范围是一种非常方便的方法。我是这样做的:

NSMutableAttributedString *goodText = [[NSMutableAttributedString alloc] initWithString:articleText];

NSRange range = [articleText rangeOfString:@"\\[.+?\\]" options:NSRegularExpressionSearch|NSCaseInsensitiveSearch];
if (range.location != NSNotFound) {
    [goodText addAttribute:NSFontAttributeName value:[UIFont fontWithName:@"Georgia" size:16] range:range];
    [goodText addAttribute:NSForegroundColorAttributeName value:[UIColor brownColor] range:range];
}

NSString *regEx = [NSString stringWithFormat:@"%@.+?\\s", [self.article.titleText substringToIndex:0]];
range = [articleText rangeOfString:regEx options:NSRegularExpressionSearch|NSCaseInsensitiveSearch];
if (range.location != NSNotFound) {
    [goodText addAttribute:NSFontAttributeName value:[UIFont fontWithName:@"Georgia-Bold" size:20] range:range];
    [goodText addAttribute:NSForegroundColorAttributeName value:[UIColor blueColor] range:range];
}

[self.textView setAttributedText:goodText];

我正在搜索可用属性的列表,但在这里和类引用的第一页中都没有找到它们。所以我决定在这里发布相关信息。

标准属性

带属性字符串支持以下文本的标准属性。如果键不在字典中,则使用下面描述的默认值。

NSString *NSFontAttributeName;
NSString *NSParagraphStyleAttributeName;
NSString *NSForegroundColorAttributeName;
NSString *NSUnderlineStyleAttributeName;
NSString *NSSuperscriptAttributeName;
NSString *NSBackgroundColorAttributeName;
NSString *NSAttachmentAttributeName;
NSString *NSLigatureAttributeName;
NSString *NSBaselineOffsetAttributeName;
NSString *NSKernAttributeName;
NSString *NSLinkAttributeName;
NSString *NSStrokeWidthAttributeName;
NSString *NSStrokeColorAttributeName;
NSString *NSUnderlineColorAttributeName;
NSString *NSStrikethroughStyleAttributeName;
NSString *NSStrikethroughColorAttributeName;
NSString *NSShadowAttributeName;
NSString *NSObliquenessAttributeName;
NSString *NSExpansionAttributeName;
NSString *NSCursorAttributeName;
NSString *NSToolTipAttributeName;
NSString *NSMarkedClauseSegmentAttributeName;
NSString *NSWritingDirectionAttributeName;
NSString *NSVerticalGlyphFormAttributeName;
NSString *NSTextAlternativesAttributeName;

NSAttributedString编程指南

完整的类参考在这里。

其他回答

问题已经有了答案……但是我想展示如何用NSAttributedString添加阴影和改变字体,这样当人们搜索这个主题时,他们就不用一直找了。

#define FONT_SIZE 20
#define FONT_HELVETICA @"Helvetica-Light"
#define BLACK_SHADOW [UIColor colorWithRed:40.0f/255.0f green:40.0f/255.0f blue:40.0f/255.0f alpha:0.4f]

NSString*myNSString = @"This is my string.\nIt goes to a second line.";                

NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
               paragraphStyle.alignment = NSTextAlignmentCenter;
             paragraphStyle.lineSpacing = FONT_SIZE/2;
                     UIFont * labelFont = [UIFont fontWithName:FONT_HELVETICA size:FONT_SIZE];
                   UIColor * labelColor = [UIColor colorWithWhite:1 alpha:1];
                       NSShadow *shadow = [[NSShadow alloc] init];
                 [shadow setShadowColor : BLACK_SHADOW];
                [shadow setShadowOffset : CGSizeMake (1.0, 1.0)];
            [shadow setShadowBlurRadius : 1];

NSAttributedString *labelText = [[NSAttributedString alloc] initWithString : myNSString
                      attributes : @{
   NSParagraphStyleAttributeName : paragraphStyle,
             NSKernAttributeName : @2.0,
             NSFontAttributeName : labelFont,
  NSForegroundColorAttributeName : labelColor,
           NSShadowAttributeName : shadow }];

这是一个Swift版本…

警告! 这适用于4s。

5s你必须改变所有的Float值为Double值(因为编译器还没有正确工作)

字体选择的Swift枚举:

enum FontValue: Int {
    case FVBold = 1 , FVCondensedBlack, FVMedium, FVHelveticaNeue, FVLight, FVCondensedBold, FVLightItalic, FVUltraLightItalic, FVUltraLight, FVBoldItalic, FVItalic
}

用于enum访问的Swift数组(因为enum不能使用'-'):

func helveticaFont (index:Int) -> (String) {
    let fontArray = [
    "HelveticaNeue-Bold",
    "HelveticaNeue-CondensedBlack",
    "HelveticaNeue-Medium",
    "HelveticaNeue",
    "HelveticaNeue-Light",
    "HelveticaNeue-CondensedBold",
    "HelveticaNeue-LightItalic",
    "HelveticaNeue-UltraLightItalic",
    "HelveticaNeue-UltraLight",
    "HelveticaNeue-BoldItalic",
    "HelveticaNeue-Italic",
    ]
    return fontArray[index]
}

Swift属性文本函数:

func myAttributedText (myString:String, mySize: Float, myFont:FontValue) -> (NSMutableAttributedString) {

    let shadow = NSShadow()
    shadow.shadowColor = UIColor.textShadowColor()
    shadow.shadowOffset = CGSizeMake (1.0, 1.0)
    shadow.shadowBlurRadius = 1

    let paragraphStyle = NSMutableParagraphStyle.alloc()
    paragraphStyle.lineHeightMultiple = 1
    paragraphStyle.lineBreakMode = NSLineBreakMode.ByWordWrapping
    paragraphStyle.alignment = NSTextAlignment.Center

    let labelFont = UIFont(name: helveticaFont(myFont.toRaw()), size: mySize)
    let labelColor = UIColor.whiteColor()

    let myAttributes :Dictionary = [NSParagraphStyleAttributeName : paragraphStyle,
                                              NSKernAttributeName : 3, // (-1,5)
                                              NSFontAttributeName : labelFont,
                                   NSForegroundColorAttributeName : labelColor,
                                            NSShadowAttributeName : shadow]

    let myAttributedString = NSMutableAttributedString (string: myString, attributes:myAttributes)

    // add new color 
    let secondColor = UIColor.blackColor()
    let stringArray = myString.componentsSeparatedByString(" ")
    let firstString: String? = stringArray.first
    let letterCount = countElements(firstString!)
    if firstString {
        myAttributedString.addAttributes([NSForegroundColorAttributeName:secondColor], range:NSMakeRange(0,letterCount))
    }

    return  myAttributedString
}

第一个和最后一个扩展名用于查找字符串数组中的范围:

extension Array {
    var last: T? {
        if self.isEmpty {
            NSLog("array crash error - please fix")
            return self [0]
        } else {
            return self[self.endIndex - 1]
        }
    }
}

extension Array {
    var first: T? {
        if self.isEmpty {
            NSLog("array crash error - please fix")
            return self [0]
        } else {
            return self [0]
        }
    }
}

新的颜色:

extension UIColor {
    class func shadowColor() -> UIColor {
        return UIColor(red: 0.0/255.0, green: 0.0/255.0, blue: 0.0/255.0, alpha: 0.3)
    }
    class func textShadowColor() -> UIColor {
        return UIColor(red: 50.0/255.0, green: 50.0/255.0, blue: 50.0/255.0, alpha: 0.5)
    }
    class func pastelBlueColor() -> UIColor {
        return UIColor(red: 176.0/255.0, green: 186.0/255.0, blue: 255.0/255.0, alpha: 1)
    }
    class func pastelYellowColor() -> UIColor {
        return UIColor(red: 255.0/255.0, green: 238.0/255.0, blue: 140.0/255.0, alpha: 1)
    }
}

我的宏替换:

enum MyConstants: Float {
    case CornerRadius = 5.0
}

我的按钮制造商w/带属性的文本:

func myButtonMaker (myView:UIView) -> UIButton {

    let myButton = UIButton.buttonWithType(.System) as UIButton
    myButton.backgroundColor = UIColor.pastelBlueColor()
    myButton.showsTouchWhenHighlighted = true;
    let myCGSize:CGSize = CGSizeMake(100.0, 50.0)
    let myFrame = CGRectMake(myView.frame.midX - myCGSize.height,myView.frame.midY - 2 * myCGSize.height,myCGSize.width,myCGSize.height)
    myButton.frame = myFrame
    let myTitle = myAttributedText("Button",20.0,FontValue.FVLight)
    myButton.setAttributedTitle(myTitle, forState:.Normal)

    myButton.layer.cornerRadius = myButton.bounds.size.width / MyConstants.CornerRadius.toRaw()
    myButton.setTitleColor(UIColor.whiteColor(), forState: .Normal)
    myButton.tag = 100
    myButton.bringSubviewToFront(myView)
    myButton.layerGradient()

    myView.addSubview(myButton)

    return  myButton
}

我的UIView/UILabel maker w/带属性的文本,阴影和圆角:

func myLabelMaker (myView:UIView) -> UIView {

    let myFrame = CGRectMake(myView.frame.midX / 2 , myView.frame.midY / 2, myView.frame.width/2, myView.frame.height/2)
    let mylabelFrame = CGRectMake(0, 0, myView.frame.width/2, myView.frame.height/2)

    let myBaseView = UIView()
    myBaseView.frame = myFrame
    myBaseView.backgroundColor = UIColor.clearColor()

    let myLabel = UILabel()
    myLabel.backgroundColor=UIColor.pastelYellowColor()
    myLabel.frame = mylabelFrame

    myLabel.attributedText = myAttributedText("This is my String",20.0,FontValue.FVLight)
    myLabel.numberOfLines = 5
    myLabel.tag = 100
    myLabel.layer.cornerRadius = myLabel.bounds.size.width / MyConstants.CornerRadius.toRaw()
    myLabel.clipsToBounds = true
    myLabel.layerborders()

    myBaseView.addSubview(myLabel)

    myBaseView.layerShadow()
    myBaseView.layerGradient()

    myView.addSubview(myBaseView)

    return myLabel
}

通用阴影添加:

func viewshadow<T where T: UIView> (shadowObject: T)
{
    let layer = shadowObject.layer
    let radius = shadowObject.frame.size.width / MyConstants.CornerRadius.toRaw();
    layer.borderColor = UIColor.whiteColor().CGColor
    layer.borderWidth = 0.8
    layer.cornerRadius = radius
    layer.shadowOpacity = 1
    layer.shadowRadius = 3
    layer.shadowOffset = CGSizeMake(2.0,2.0)
    layer.shadowColor = UIColor.shadowColor().CGColor
}

视图样式的视图扩展:

extension UIView {
    func layerborders() {
        let layer = self.layer
        let frame = self.frame
        let myColor = self.backgroundColor
        layer.borderColor = myColor.CGColor
        layer.borderWidth = 10.8
        layer.cornerRadius = layer.borderWidth / MyConstants.CornerRadius.toRaw()
    }

    func layerShadow() {
        let layer = self.layer
        let frame = self.frame
        layer.cornerRadius = layer.borderWidth / MyConstants.CornerRadius.toRaw()
        layer.shadowOpacity = 1
        layer.shadowRadius = 3
        layer.shadowOffset = CGSizeMake(2.0,2.0)
        layer.shadowColor = UIColor.shadowColor().CGColor
    }

    func layerGradient() {
        let layer = CAGradientLayer()
        let size = self.frame.size
        layer.frame.size = size
        layer.frame.origin = CGPointMake(0.0,0.0)
        layer.cornerRadius = layer.bounds.size.width / MyConstants.CornerRadius.toRaw();

        var color0 = CGColorCreateGenericRGB(250.0/255, 250.0/255, 250.0/255, 0.5)
        var color1 = CGColorCreateGenericRGB(200.0/255, 200.0/255, 200.0/255, 0.1)
        var color2 = CGColorCreateGenericRGB(150.0/255, 150.0/255, 150.0/255, 0.1)
        var color3 = CGColorCreateGenericRGB(100.0/255, 100.0/255, 100.0/255, 0.1)
        var color4 = CGColorCreateGenericRGB(50.0/255, 50.0/255, 50.0/255, 0.1)
        var color5 = CGColorCreateGenericRGB(0.0/255, 0.0/255, 0.0/255, 0.1)
        var color6 = CGColorCreateGenericRGB(150.0/255, 150.0/255, 150.0/255, 0.1)

        layer.colors = [color0,color1,color2,color3,color4,color5,color6]
        self.layer.insertSublayer(layer, atIndex: 2)
    }
}

实际视图didload函数:

func buttonPress (sender:UIButton!) {
    NSLog("%@", "ButtonPressed")
}

override func viewDidLoad() {
    super.viewDidLoad()

    let myLabel = myLabelMaker(myView)
    let myButton = myButtonMaker(myView)

    myButton.addTarget(self, action: "buttonPress:", forControlEvents:UIControlEvents.TouchUpInside)

    viewshadow(myButton)
    viewshadow(myLabel)

}

我认为,使用正则表达式来查找应用属性的范围是一种非常方便的方法。我是这样做的:

NSMutableAttributedString *goodText = [[NSMutableAttributedString alloc] initWithString:articleText];

NSRange range = [articleText rangeOfString:@"\\[.+?\\]" options:NSRegularExpressionSearch|NSCaseInsensitiveSearch];
if (range.location != NSNotFound) {
    [goodText addAttribute:NSFontAttributeName value:[UIFont fontWithName:@"Georgia" size:16] range:range];
    [goodText addAttribute:NSForegroundColorAttributeName value:[UIColor brownColor] range:range];
}

NSString *regEx = [NSString stringWithFormat:@"%@.+?\\s", [self.article.titleText substringToIndex:0]];
range = [articleText rangeOfString:regEx options:NSRegularExpressionSearch|NSCaseInsensitiveSearch];
if (range.location != NSNotFound) {
    [goodText addAttribute:NSFontAttributeName value:[UIFont fontWithName:@"Georgia-Bold" size:20] range:range];
    [goodText addAttribute:NSForegroundColorAttributeName value:[UIColor blueColor] range:range];
}

[self.textView setAttributedText:goodText];

我正在搜索可用属性的列表,但在这里和类引用的第一页中都没有找到它们。所以我决定在这里发布相关信息。

标准属性

带属性字符串支持以下文本的标准属性。如果键不在字典中,则使用下面描述的默认值。

NSString *NSFontAttributeName;
NSString *NSParagraphStyleAttributeName;
NSString *NSForegroundColorAttributeName;
NSString *NSUnderlineStyleAttributeName;
NSString *NSSuperscriptAttributeName;
NSString *NSBackgroundColorAttributeName;
NSString *NSAttachmentAttributeName;
NSString *NSLigatureAttributeName;
NSString *NSBaselineOffsetAttributeName;
NSString *NSKernAttributeName;
NSString *NSLinkAttributeName;
NSString *NSStrokeWidthAttributeName;
NSString *NSStrokeColorAttributeName;
NSString *NSUnderlineColorAttributeName;
NSString *NSStrikethroughStyleAttributeName;
NSString *NSStrikethroughColorAttributeName;
NSString *NSShadowAttributeName;
NSString *NSObliquenessAttributeName;
NSString *NSExpansionAttributeName;
NSString *NSCursorAttributeName;
NSString *NSToolTipAttributeName;
NSString *NSMarkedClauseSegmentAttributeName;
NSString *NSWritingDirectionAttributeName;
NSString *NSVerticalGlyphFormAttributeName;
NSString *NSTextAlternativesAttributeName;

NSAttributedString编程指南

完整的类参考在这里。

斯威夫特4

let combination = NSMutableAttributedString()

var part1 = NSMutableAttributedString()
var part2 = NSMutableAttributedString()
var part3 = NSMutableAttributedString()

let attrRegular = [NSAttributedStringKey.font : UIFont(name: "Palatino-Roman", size: 15)]

let attrBold:Dictionary = [NSAttributedStringKey.font : UIFont(name: "Raleway-SemiBold", size: 15)]

let attrBoldWithColor: Dictionary = [NSAttributedStringKey.font : UIFont(name: "Raleway-SemiBold", size: 15),
                                 NSAttributedStringKey.foregroundColor: UIColor.red]

if let regular = attrRegular as? [NSAttributedStringKey : NSObject]{
    part1 = NSMutableAttributedString(string: "first", attributes: regular)

}
if let bold = attrRegular as? [NSAttributedStringKey : NSObject]{
    part2 = NSMutableAttributedString(string: "second", attributes: bold)
}

if let boldWithColor = attrBoldWithColor as? [NSAttributedStringKey : NSObject]{
    part3 = NSMutableAttributedString(string: "third", attributes: boldWithColor)
}

combination.append(part1)
combination.append(part2)
combination.append(part3)

属性列表请参见这里的NSAttributedStringKey在苹果文档

带属性字符串扩展的更简单的解决方案。

extension NSMutableAttributedString {

    // this function attaches color to string    
    func setColorForText(textToFind: String, withColor color: UIColor) {
        let range: NSRange = self.mutableString.range(of: textToFind, options: .caseInsensitive)
        self.addAttribute(NSAttributedStringKey.foregroundColor, value: color, range: range)
    }

}

试试这个,看看(在Swift 3和4中测试)

let label = UILabel()
label.frame = CGRect(x: 120, y: 100, width: 200, height: 30)
let first = "first"
let second = "second"
let third = "third"
let stringValue = "\(first)\(second)\(third)"  // or direct assign single string value like "firstsecondthird"

let attributedString: NSMutableAttributedString = NSMutableAttributedString(string: stringValue)
attributedString.setColorForText(textToFind: first, withColor: UIColor.red)   // use variable for string "first"
attributedString.setColorForText(textToFind: "second", withColor: UIColor.green) // or direct string like this "second"
attributedString.setColorForText(textToFind: third, withColor: UIColor.blue)
label.font = UIFont.systemFont(ofSize: 26)
label.attributedText = attributedString
self.view.addSubview(label)

以下是预期结果:

- (void)changeColorWithString:(UILabel *)uilabel stringToReplace:(NSString *) stringToReplace uiColor:(UIColor *) uiColor{
    NSMutableAttributedString *text =
    [[NSMutableAttributedString alloc]
     initWithAttributedString: uilabel.attributedText];

    [text addAttribute: NSForegroundColorAttributeName value:uiColor range:[uilabel.text rangeOfString:stringToReplace]];

    [uilabel setAttributedText: text];

}