我有一个UILabel,我想在顶部和底部添加空格。在限制最小高度的情况下,我将其修改为:

为了做到这一点,我使用了:

override func drawTextInRect(rect: CGRect) {
    var insets: UIEdgeInsets = UIEdgeInsets(top: 0.0, left: 10.0, bottom: 0.0, right: 10.0)
    super.drawTextInRect(UIEdgeInsetsInsetRect(rect, insets))
}

但我必须找到不同的方法,因为如果我写了超过两行,问题是一样的:


当前回答

根据Swift 4.2 (Xcode 10 beta 6)"UIEdgeInsetsInsetRect"已弃用。 我还将类声明为public以使其更有用。

public class UIPaddedLabel: UILabel {

    @IBInspectable var topInset: CGFloat = 5.0
    @IBInspectable var bottomInset: CGFloat = 5.0
    @IBInspectable var leftInset: CGFloat = 7.0
    @IBInspectable var rightInset: CGFloat = 7.0

    public override func drawText(in rect: CGRect) {
        let insets = UIEdgeInsets.init(top: topInset, left: leftInset, bottom: bottomInset, right: rightInset)
        super.drawText(in: rect.inset(by: insets))
    }

    public override var intrinsicContentSize: CGSize {
        let size = super.intrinsicContentSize
        return CGSize(width: size.width + leftInset + rightInset,
                      height: size.height + topInset + bottomInset)
    }

    public override func sizeToFit() {
        super.sizeThatFits(intrinsicContentSize)
    }
}

其他回答

只需使用一个UIView作为一个superview,并定义一个固定的边距标签与自动布局。

如果你想坚持使用UILabel,而不子类化它,Mundi已经给了你一个明确的解决方案。

如果你想避免用UIView来包装UILabel,你可以使用UITextView来支持UIEdgeInsets (padding)或者子类UILabel来支持UIEdgeInsets。

使用UITextView只需要提供insets (Objective-C):

textView.textContainerInset = UIEdgeInsetsMake(10, 0, 10, 0);

另外,如果你子类化UILabel,这种方法的一个例子是重写drawTextInRect方法 (objective - c)

- (void)drawTextInRect:(CGRect)uiLabelRect {
    UIEdgeInsets myLabelInsets = {10, 0, 10, 0};
    [super drawTextInRect:UIEdgeInsetsInsetRect(uiLabelRect, myLabelInsets)];
}

您还可以为您的新子类UILabel提供带有insets变量的TOP, LEFT, BOTTOM和RIGHT。

一个示例代码可以是:

In .h (Objective-C)

float topInset, leftInset,bottomInset, rightInset;

在。m (Objective-C)中

- (void)drawTextInRect:(CGRect)uiLabelRect {
    [super drawTextInRect:UIEdgeInsetsInsetRect(uiLabelRect, UIEdgeInsetsMake(topInset,leftInset,bottomInset,rightInset))];
}

从我所看到的,似乎你必须在子类化UILabel时重写它的intrinsicContentSize。

所以你应该像这样重写intrinsicContentSize:

- (CGSize) intrinsicContentSize {
    CGSize intrinsicSuperViewContentSize = [super intrinsicContentSize] ;
    intrinsicSuperViewContentSize.height += topInset + bottomInset ;
    intrinsicSuperViewContentSize.width += leftInset + rightInset ;
    return intrinsicSuperViewContentSize ;
}

并添加以下方法来编辑您的嵌入,而不是单独编辑它们:

- (void) setContentEdgeInsets:(UIEdgeInsets)edgeInsets {
    topInset = edgeInsets.top;
    leftInset = edgeInsets.left;
    rightInset = edgeInsets.right;
    bottomInset = edgeInsets.bottom;
    [self invalidateIntrinsicContentSize] ;
}

它将更新UILabel的大小,以匹配边缘插入并覆盖您提到的多行需求。

经过搜索,我找到了一个IPInsetLabel的Gist。如果这些方法都不起作用,你可以尝试一下。

关于这件事,还有一个类似的问题(重复)。 有关可用解决方案的完整列表,请参阅以下答案:UILabel文本边距

objective - c

基于Tai Le的回答,它在一个Interface Builder Designable中实现了这个特性,下面是Objective-C版本。

把这个放在YourLabel.h文件中:

@interface YourLabel : UILabel

@property IBInspectable CGFloat topInset;
@property IBInspectable CGFloat bottomInset;
@property IBInspectable CGFloat leftInset;
@property IBInspectable CGFloat rightInset;

@end

这个会放在yourlabel。m文件中:

IB_DESIGNABLE

@implementation YourLabel

#pragma mark - Super

- (instancetype)initWithCoder:(NSCoder *)aDecoder {
    self = [super initWithCoder:aDecoder];
    if (self) {
        self.topInset = 0;
        self.bottomInset = 0;
        self.leftInset = 0;
        self.rightInset = 0;
    }
    return self;
}

- (void)drawTextInRect:(CGRect)rect {
    UIEdgeInsets insets = UIEdgeInsetsMake(self.topInset, self.leftInset, self.bottomInset, self.rightInset);
    [super drawTextInRect:UIEdgeInsetsInsetRect(rect, insets)];
}

- (CGSize)intrinsicContentSize {
    
    CGSize size = [super intrinsicContentSize];
    return CGSizeMake(size.width + self.leftInset + self.rightInset,
                      size.height + self.topInset + self.bottomInset);
}

@end

然后,在XIB文件或故事板中指定类后,您可以直接在Interface Builder中修改YourLabel嵌入,嵌入的默认值为零。

使用UILabel扩展的Swift 5示例

使用下面的代码,设置你的边距就像label. setmargin(15)一样简单。

extension UILabel {
    func setMargins(_ margin: CGFloat = 10) {
        if let textString = self.text {
            let paragraphStyle = NSMutableParagraphStyle()
            paragraphStyle.firstLineHeadIndent = margin
            paragraphStyle.headIndent = margin
            paragraphStyle.tailIndent = -margin
            let attributedString = NSMutableAttributedString(string: textString)
            attributedString.addAttribute(.paragraphStyle, value: paragraphStyle, range: NSRange(location: 0, length: attributedString.length))
            attributedText = attributedString
        }
    }
}

简单的方法

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.

        self.view.addSubview(makeLabel("my title",x: 0, y: 100, w: 320, h: 30))
    }

    func makeLabel(title:String, x:CGFloat, y:CGFloat, w:CGFloat, h:CGFloat)->UILabel{
        var myLabel : UILabel = UILabel(frame: CGRectMake(x,y,w,h))
        myLabel.textAlignment = NSTextAlignment.Right

        // inser last char to right
        var titlePlus1char = "\(title)1"
        myLabel.text = titlePlus1char
        var titleSize:Int = count(titlePlus1char)-1

        myLabel.textColor = UIColor(red:1.0, green:1.0,blue:1.0,alpha:1.0)
        myLabel.backgroundColor = UIColor(red: 214/255, green: 167/255, blue: 0/255,alpha:1.0)


        // create myMutable String
        var myMutableString = NSMutableAttributedString()

        // create myMutable font
        myMutableString = NSMutableAttributedString(string: titlePlus1char, attributes: [NSFontAttributeName:UIFont(name: "HelveticaNeue", size: 20)!])

        // set margin size
        myMutableString.addAttribute(NSFontAttributeName, value: UIFont(name: "HelveticaNeue", size: 10)!, range: NSRange(location: titleSize,length: 1))

        // set last char to alpha 0
        myMutableString.addAttribute(NSForegroundColorAttributeName, value: UIColor(red:1.0, green:1.0,blue:1.0,alpha:0), range: NSRange(location: titleSize,length: 1))

        myLabel.attributedText = myMutableString

        return myLabel
    }


    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

}