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
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
}
}
}
其他回答
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
}
}
}
斯威夫特4
易于使用的解决方案，可用于项目中的所有UILabel子。
例子:
let label = UILabel()
label.<Do something>
label.padding = UIEdgeInsets(top: 0, left: 16, bottom: 0, right: 0)
UILabel扩展
import UIKit
extension UILabel {
private struct AssociatedKeys {
static var padding = UIEdgeInsets()
}
public var padding: UIEdgeInsets? {
get {
return objc_getAssociatedObject(self, &AssociatedKeys.padding) as? UIEdgeInsets
}
set {
if let newValue = newValue {
objc_setAssociatedObject(self, &AssociatedKeys.padding, newValue as UIEdgeInsets?, objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN_NONATOMIC)
}
}
}
override open func draw(_ rect: CGRect) {
if let insets = padding {
self.drawText(in: rect.inset(by: insets))
} else {
self.drawText(in: rect)
}
}
override open var intrinsicContentSize: CGSize {
guard let text = self.text else { return super.intrinsicContentSize }
var contentSize = super.intrinsicContentSize
var textWidth: CGFloat = frame.size.width
var insetsHeight: CGFloat = 0.0
var insetsWidth: CGFloat = 0.0
if let insets = padding {
insetsWidth += insets.left + insets.right
insetsHeight += insets.top + insets.bottom
textWidth -= insetsWidth
}
let newSize = text.boundingRect(with: CGSize(width: textWidth, height: CGFloat.greatestFiniteMagnitude),
options: NSStringDrawingOptions.usesLineFragmentOrigin,
attributes: [NSAttributedString.Key.font: self.font], context: nil)
contentSize.height = ceil(newSize.size.height) + insetsHeight
contentSize.width = ceil(newSize.size.width) + insetsWidth
return contentSize
}
}
只需使用自动布局:
let paddedWidth = myLabel.intrinsicContentSize.width + 2 * padding
myLabel.widthAnchor.constraint(equalToConstant: paddedWidth).isActive = true
完成了。
简单的填充:
import UIKit
class NewLabel: UILabel {
override func textRectForBounds(bounds: CGRect, limitedToNumberOfLines numberOfLines: Int) -> CGRect {
return CGRectInset(self.bounds, CGFloat(15.0), CGFloat(15.0))
}
override func drawRect(rect: CGRect) {
super.drawTextInRect(CGRectInset(self.bounds,CGFloat(5.0), CGFloat(5.0)))
}
}
我在任何地方都没有看到这个答案。我的技巧是在标签上设置宽度限制，并在设置标签文本时调整宽度。
self.myLabel.text = myString;
UIFont * const font = [UIFont systemFontOfSize:17 weight:UIFontWeightRegular]; // Change to your own label font.
CGSize const size = CGSizeMake(INFINITY, 18); // 18 is height of label.
CGFloat const textWidth = [myString boundingRectWithSize:size options:NSStringDrawingUsesLineFragmentOrigin attributes:@{NSFontAttributeName: font} context:nil].size.width;
self.myLabelWidthConstraint.constant = textWidth + 20; // 10 padding on each side. Also, set text alignment to centre.
