如何在UILabel中包含粗体和非粗体文本?
我不想使用UIWebView...我也读到可能可以使用NSAttributedString实现这个目标,但我不知道该如何使用。有任何想法吗?
苹果在他们的一些应用程序中实现了这一点;
示例截图:
谢谢! - Dom
如何在UILabel中包含粗体和非粗体文本?
我不想使用UIWebView...我也读到可能可以使用NSAttributedString实现这个目标,但我不知道该如何使用。有任何想法吗?
苹果在他们的一些应用程序中实现了这一点;
示例截图:
谢谢! - Dom
在Swift中,除了语法更短,因此一切变得非常简单外,我们不必再处理iOS5的旧东西:
Swift 5
func attributedString(from string: String, nonBoldRange: NSRange?) -> NSAttributedString {
let fontSize = UIFont.systemFontSize
let attrs = [
NSAttributedString.Key.font: UIFont.boldSystemFont(ofSize: fontSize),
NSAttributedString.Key.foregroundColor: UIColor.black
]
let nonBoldAttribute = [
NSAttributedString.Key.font: UIFont.systemFont(ofSize: fontSize),
]
let attrStr = NSMutableAttributedString(string: string, attributes: attrs)
if let range = nonBoldRange {
attrStr.setAttributes(nonBoldAttribute, range: range)
}
return attrStr
}
Swift 3
func attributedString(from string: String, nonBoldRange: NSRange?) -> NSAttributedString {
let fontSize = UIFont.systemFontSize
let attrs = [
NSFontAttributeName: UIFont.boldSystemFont(ofSize: fontSize),
NSForegroundColorAttributeName: UIColor.black
]
let nonBoldAttribute = [
NSFontAttributeName: UIFont.systemFont(ofSize: fontSize),
]
let attrStr = NSMutableAttributedString(string: string, attributes: attrs)
if let range = nonBoldRange {
attrStr.setAttributes(nonBoldAttribute, range: range)
}
return attrStr
}
使用方法:
let targetString = "Updated 2012/10/14 21:59 PM"
let range = NSMakeRange(7, 12)
let label = UILabel(frame: CGRect(x:0, y:0, width:350, height:44))
label.backgroundColor = UIColor.white
label.attributedText = attributedString(from: targetString, nonBoldRange: range)
label.sizeToFit()
有些人评论了国际化的问题。我个人认为这超出了本问题的范围,但出于教学目的,以下是我的解决方案。
// Date we want to show
let date = Date()
// Create the string.
// I don't set the locale because the default locale of the formatter is `NSLocale.current` so it's good for internationalisation :p
let formatter = DateFormatter()
formatter.dateStyle = .medium
formatter.timeStyle = .short
let targetString = String(format: NSLocalizedString("Update %@", comment: "Updated string format"),
formatter.string(from: date))
// Find the range of the non-bold part
formatter.timeStyle = .none
let nonBoldRange = targetString.range(of: formatter.string(from: date))
// Convert Range<Int> into NSRange
let nonBoldNSRange: NSRange? = nonBoldRange == nil ?
nil :
NSMakeRange(targetString.distance(from: targetString.startIndex, to: nonBoldRange!.lowerBound),
targetString.distance(from: nonBoldRange!.lowerBound, to: nonBoldRange!.upperBound))
// Now just build the attributed string as before :)
label.attributedText = attributedString(from: targetString,
nonBoldRange: nonBoldNSRange)
结果(假设有英语和日语的Localizable.strings可用)
在iOS6中,UILabel
,UIButton
,UITextView
和UITextField
支持属性字符串,这意味着我们不需要创建CATextLayer
作为属性字符串的接收者。此外,为了创建属性字符串,我们不再需要使用CoreText :) 我们在obj-c Foundation.framework中有新的类,如NSParagraphStyle
和其他常量,这将使我们的生活更轻松。耶!
因此,如果我们有这个字符串:
NSString *text = @"Updated: 2012/10/14 21:59"
if ([_label respondsToSelector:@selector(setAttributedText:)])
{
// iOS6 and above : Use NSAttributedStrings
// Create the attributes
const CGFloat fontSize = 13;
NSDictionary *attrs = @{
NSFontAttributeName:[UIFont boldSystemFontOfSize:fontSize],
NSForegroundColorAttributeName:[UIColor whiteColor]
};
NSDictionary *subAttrs = @{
NSFontAttributeName:[UIFont systemFontOfSize:fontSize]
};
// Range of " 2012/10/14 " is (8,12). Ideally it shouldn't be hardcoded
// This example is about attributed strings in one label
// not about internationalisation, so we keep it simple :)
// For internationalisation example see above code in swift
const NSRange range = NSMakeRange(8,12);
// Create the attributed string (text + attributes)
NSMutableAttributedString *attributedText =
[[NSMutableAttributedString alloc] initWithString:text
attributes:attrs];
[attributedText setAttributes:subAttrs range:range];
// Set it in our UILabel and we are done!
[_label setAttributedText:attributedText];
} else {
// iOS5 and below
// Here we have some options too. The first one is to do something
// less fancy and show it just as plain text without attributes.
// The second is to use CoreText and get similar results with a bit
// more of code. Interested people please look down the old answer.
// Now I am just being lazy so :p
[_label setText:text];
}
这里有一对很好的入门博客文章在这里,由invasivecode的人撰写,用更多示例解释了NSAttributedString
的用途,可以查看"iOS 6下NSAttributedString简介"和"使用Interface Builder创建带属性的字符串(iOS)" :)
附注:上述代码应该能够正常工作,但它是脑部编译的。我希望这已经足够了:)
使用带有NSAttributedString的CATextLayer!比两个UILabel更轻巧和简单。 (iOS 3.2及以上)
示例。
不要忘记添加QuartzCore框架(CALayers所需),以及CoreText(属性字符串所需)。
#import <QuartzCore/QuartzCore.h>
#import <CoreText/CoreText.h>
以下示例将向导航控制器的工具栏添加一个子层,类似于 iPhone 上的 Mail.app。 :)
- (void)setRefreshDate:(NSDate *)aDate
{
[aDate retain];
[refreshDate release];
refreshDate = aDate;
if (refreshDate) {
/* Create the text for the text layer*/
NSDateFormatter *df = [[NSDateFormatter alloc] init];
[df setDateFormat:@"MM/dd/yyyy hh:mm"];
NSString *dateString = [df stringFromDate:refreshDate];
NSString *prefix = NSLocalizedString(@"Updated", nil);
NSString *text = [NSString stringWithFormat:@"%@: %@",prefix, dateString];
[df release];
/* Create the text layer on demand */
if (!_textLayer) {
_textLayer = [[CATextLayer alloc] init];
//_textLayer.font = [UIFont boldSystemFontOfSize:13].fontName; // not needed since `string` property will be an NSAttributedString
_textLayer.backgroundColor = [UIColor clearColor].CGColor;
_textLayer.wrapped = NO;
CALayer *layer = self.navigationController.toolbar.layer; //self is a view controller contained by a navigation controller
_textLayer.frame = CGRectMake((layer.bounds.size.width-180)/2 + 10, (layer.bounds.size.height-30)/2 + 10, 180, 30);
_textLayer.contentsScale = [[UIScreen mainScreen] scale]; // looks nice in retina displays too :)
_textLayer.alignmentMode = kCAAlignmentCenter;
[layer addSublayer:_textLayer];
}
/* Create the attributes (for the attributed string) */
CGFloat fontSize = 13;
UIFont *boldFont = [UIFont boldSystemFontOfSize:fontSize];
CTFontRef ctBoldFont = CTFontCreateWithName((CFStringRef)boldFont.fontName, boldFont.pointSize, NULL);
UIFont *font = [UIFont systemFontOfSize:13];
CTFontRef ctFont = CTFontCreateWithName((CFStringRef)font.fontName, font.pointSize, NULL);
CGColorRef cgColor = [UIColor whiteColor].CGColor;
NSDictionary *attributes = [NSDictionary dictionaryWithObjectsAndKeys:
(id)ctBoldFont, (id)kCTFontAttributeName,
cgColor, (id)kCTForegroundColorAttributeName, nil];
CFRelease(ctBoldFont);
NSDictionary *subAttributes = [NSDictionary dictionaryWithObjectsAndKeys:(id)ctFont, (id)kCTFontAttributeName, nil];
CFRelease(ctFont);
/* Create the attributed string (text + attributes) */
NSMutableAttributedString *attrStr = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
[attrStr addAttributes:subAttributes range:NSMakeRange(prefix.length, 12)]; //12 is the length of " MM/dd/yyyy/ "
/* Set the attributes string in the text layer :) */
_textLayer.string = attrStr;
[attrStr release];
_textLayer.opacity = 1.0;
} else {
_textLayer.opacity = 0.0;
_textLayer.string = nil;
}
}
[NSDictionary dictionaryWithObjectsAndKeys: boldFont, NSFontAttributeName, foregroundColor, NSForegroundColorAttributeName, nil]
可以变成 @{ NSFontAttributeName: boldFont, NSForegroundColorAttributeName: foregroundColor }
。 - PatrickNLT{
),而不是方括号([
)。 - PatrickNLT尝试一下UILabel上的类别:
以下是它的使用方法:
myLabel.text = @"Updated: 2012/10/14 21:59 PM";
[myLabel boldSubstring: @"Updated:"];
[myLabel boldSubstring: @"21:59 PM"];
这是分类的部分。
UILabel+Boldify.h
- (void) boldSubstring: (NSString*) substring;
- (void) boldRange: (NSRange) range;
UILabel+Boldify.m
- (void) boldRange: (NSRange) range {
if (![self respondsToSelector:@selector(setAttributedText:)]) {
return;
}
NSMutableAttributedString *attributedText = [[NSMutableAttributedString alloc] initWithAttributedString:self.attributedText];
[attributedText setAttributes:@{NSFontAttributeName:[UIFont boldSystemFontOfSize:self.font.pointSize]} range:range];
self.attributedText = attributedText;
}
- (void) boldSubstring: (NSString*) substring {
NSRange range = [self.text rangeOfString:substring];
[self boldRange:range];
}
请注意,此功能仅适用于 iOS 6 及更高版本。在 iOS 5 及以下版本中将被忽略。
@ {NSFontAttributeName:[UIFont boldSystemFontOfSize:self.font.pointSize]}
我已经点赞。 - Vivienne Fosh[UIFont boldSystemFontOfSize:self.font.pointSize]
为 [UIFont fontWithName:self.font.fontName size:self.font.pointSize]
。 - lee这在界面构建器(Interface Builder)中很容易实现:
1) 在属性检查器(Attributes Inspector)中使 UILabel 变成 富文本(Attributed)
2) 选择要加粗的短语部分
3) 修改字体 (或同一字体的加粗字型) 在 字体选择器(font selector) 中
就是这样了!
基于bbrame的分类,有一些类别。它的功能类似,但允许您多次使用带有累积结果的相同UILabel
。
UILabel+Boldify.h
@interface UILabel (Boldify)
- (void) boldSubstring: (NSString*) substring;
- (void) boldRange: (NSRange) range;
@end
UILabel+Boldify.m
@implementation UILabel (Boldify)
- (void)boldRange:(NSRange)range {
if (![self respondsToSelector:@selector(setAttributedText:)]) {
return;
}
NSMutableAttributedString *attributedText;
if (!self.attributedText) {
attributedText = [[NSMutableAttributedString alloc] initWithString:self.text];
} else {
attributedText = [[NSMutableAttributedString alloc] initWithAttributedString:self.attributedText];
}
[attributedText setAttributes:@{NSFontAttributeName:[UIFont boldSystemFontOfSize:self.font.pointSize]} range:range];
self.attributedText = attributedText;
}
- (void)boldSubstring:(NSString*)substring {
NSRange range = [self.text rangeOfString:substring];
[self boldRange:range];
}
@end
有了这些更正,您可以多次使用它,例如:
myLabel.text = @"Updated: 2012/10/14 21:59 PM";
[myLabel boldSubstring: @"Updated:"];
[myLabel boldSubstring: @"21:59 PM"];
将会产生以下结果: "更新时间:2012/10/14 21:59 PM"。
这个方法对我有用:
CGFloat boldTextFontSize = 17.0f;
myLabel.text = [NSString stringWithFormat:@"%@ 2012/10/14 %@",@"Updated:",@"21:59 PM"];
NSRange range1 = [myLabel.text rangeOfString:@"Updated:"];
NSRange range2 = [myLabel.text rangeOfString:@"21:59 PM"];
NSMutableAttributedString *attributedText = [[NSMutableAttributedString alloc] initWithString:myLabel.text];
[attributedText setAttributes:@{NSFontAttributeName:[UIFont boldSystemFontOfSize:boldTextFontSize]}
range:range1];
[attributedText setAttributes:@{NSFontAttributeName:[UIFont boldSystemFontOfSize:boldTextFontSize]}
range:range2];
myLabel.attributedText = attributedText;
若要查看Swift版本,请参见此处
。extension UILabel {
func boldRange(_ range: Range<String.Index>) {
if let text = self.attributedText {
let attr = NSMutableAttributedString(attributedString: text)
let start = text.string.characters.distance(from: text.string.startIndex, to: range.lowerBound)
let length = text.string.characters.distance(from: range.lowerBound, to: range.upperBound)
attr.addAttributes([NSFontAttributeName: UIFont.boldSystemFont(ofSize: self.font.pointSize)], range: NSMakeRange(start, length))
self.attributedText = attr
}
}
func boldSubstring(_ substr: String) {
if let text = self.attributedText {
var range = text.string.range(of: substr)
let attr = NSMutableAttributedString(attributedString: text)
while range != nil {
let start = text.string.characters.distance(from: text.string.startIndex, to: range!.lowerBound)
let length = text.string.characters.distance(from: range!.lowerBound, to: range!.upperBound)
var nsRange = NSMakeRange(start, length)
let font = attr.attribute(NSFontAttributeName, at: start, effectiveRange: &nsRange) as! UIFont
if !font.fontDescriptor.symbolicTraits.contains(.traitBold) {
break
}
range = text.string.range(of: substr, options: NSString.CompareOptions.literal, range: range!.upperBound..<text.string.endIndex, locale: nil)
}
if let r = range {
boldRange(r)
}
}
}
}
也许Range和NSRange之间的转换不太好,但我没有找到更好的方法。
boldSubstring(_:)
的第二行更改为 var range = text.string.range(of: substr, options: .caseInsensitive)
,以使具有不同大小写的字符串也可以加粗。 - heyfrank看看TTTAttributedLabel。它是UILabel的替代品,通过将NSAttributedString设置为标签的文本,允许您在单个标签中具有混合字体和颜色。
UILabel *displayLabel = [[UILabel alloc] initWithFrame:/*label frame*/];
displayLabel.font = [UIFont boldSystemFontOfSize:/*bold font size*/];
NSMutableAttributedString *notifyingStr = [[NSMutableAttributedString alloc] initWithString:@"Updated: 2012/10/14 21:59 PM"];
[notifyingStr beginEditing];
[notifyingStr addAttribute:NSFontAttributeName
value:[UIFont systemFontOfSize:/*normal font size*/]
range:NSMakeRange(8,10)/*range of normal string, e.g. 2012/10/14*/];
[notifyingStr endEditing];
displayLabel.attributedText = notifyingStr; // or [displayLabel setAttributedText: notifyingStr];
NSRange range1 = [lblTermsAndCondition.text rangeOfString:NSLocalizedString(@"bold_terms", @"")];
NSRange range2 = [lblTermsAndCondition.text rangeOfString:NSLocalizedString(@"bold_policy", @"")];
NSMutableAttributedString *attributedText = [[NSMutableAttributedString alloc] initWithString:lblTermsAndCondition.text];
[attributedText setAttributes:@{NSFontAttributeName:[UIFont fontWithName:fontBold size:12.0]}
range:range1];
[attributedText setAttributes:@{NSFontAttributeName:[UIFont fontWithName:fontBold size:12.0]}
range:range2];
[attributedText addAttribute:(NSString*)kCTUnderlineStyleAttributeName
value:[NSNumber numberWithInt:kCTUnderlineStyleSingle]
range:range1];
[attributedText addAttribute:(NSString*)kCTUnderlineStyleAttributeName
value:[NSNumber numberWithInt:kCTUnderlineStyleSingle]
range:range2];
lblTermsAndCondition.attributedText = attributedText;
NSString *needToChangeStr=@"BOOK";
NSString *display_string=[NSString stringWithFormat:@"This is %@",book];
NSMutableAttributedString *attri_str=[[NSMutableAttributedString alloc]initWithString:display_string];
int begin=[display_string length]-[needToChangeStr length];
int end=[needToChangeStr length];
[attri_str addAttribute:NSFontAttributeName value:[UIFont fontWithName:@"HelveticaNeue-Bold" size:30] range:NSMakeRange(begin, end)];