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
斯威夫特3
import UIKit
class PaddingLabel: UILabel {
@IBInspectable var topInset: CGFloat = 5.0
@IBInspectable var bottomInset: CGFloat = 5.0
@IBInspectable var leftInset: CGFloat = 5.0
@IBInspectable var rightInset: CGFloat = 5.0
override func drawText(in rect: CGRect) {
let insets = UIEdgeInsets(top: topInset, left: leftInset, bottom: bottomInset, right: rightInset)
super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
}
override var intrinsicContentSize: CGSize {
get {
var contentSize = super.intrinsicContentSize
contentSize.height += topInset + bottomInset
contentSize.width += leftInset + rightInset
return contentSize
}
}
}
其他回答
我的解决方案与人们回答的类似，但添加了sizeThatFits来帮助UIKit找出正确的大小。
class InsetLabel : UILabel {
@objc var textInsets: UIEdgeInsets = .zero
override func drawText(in rect: CGRect) {
super.drawText(in: rect.inset(by: textInsets))
}
override func sizeThatFits(_ size: CGSize) -> CGSize {
var s = super.sizeThatFits(CGSize(width: size.width - (textInsets.left + textInsets.right), height: size.height - (textInsets.top + textInsets.bottom)))
s.height += textInsets.top + textInsets.bottom
return s
}
}
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)
}
}
在Swift 3中
最好最简单的方法
class UILabelPadded: UILabel {
override func drawText(in rect: CGRect) {
let insets = UIEdgeInsets.init(top: 0, left: 5, bottom: 0, right: 5)
super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
}
}
斯威夫特 4+
let paragraphStyle = NSMutableParagraphStyle()
paragraphStyle.firstLineHeadIndent = 10
// Swift 4.2++
label.attributedText = NSAttributedString(string: "Your text", attributes: [NSAttributedString.Key.paragraphStyle: paragraphStyle])
// Swift 4.1--
label.attributedText = NSAttributedString(string: "Your text", attributes: [NSAttributedStringKey.paragraphStyle: paragraphStyle])
Swift 3代码及其实现示例
class UIMarginLabel: UILabel {
var topInset: CGFloat = 0
var rightInset: CGFloat = 0
var bottomInset: CGFloat = 0
var leftInset: CGFloat = 0
override func drawText(in rect: CGRect) {
let insets: UIEdgeInsets = UIEdgeInsets(top: self.topInset, left: self.leftInset, bottom: self.bottomInset, right: self.rightInset)
self.setNeedsLayout()
return super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
}
}
class LabelVC: UIViewController {
//Outlets
@IBOutlet weak var labelWithMargin: UIMarginLabel!
override func viewDidLoad() {
super.viewDidLoad()
//Label settings.
labelWithMargin.leftInset = 10
view.layoutIfNeeded()
}
}
不要忘记在故事板标签对象中添加类名UIMarginLabel。 编码快乐!
