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
就像其他答案一样，但它修复了一个bug:
当标签。宽度由自动布局控制，有时文本会被裁剪。
@IBDesignable
class InsetLabel: UILabel {
@IBInspectable var topInset: CGFloat = 4.0
@IBInspectable var leftInset: CGFloat = 4.0
@IBInspectable var bottomInset: CGFloat = 4.0
@IBInspectable var rightInset: CGFloat = 4.0
var insets: UIEdgeInsets {
get {
return UIEdgeInsets.init(top: topInset, left: leftInset, bottom: bottomInset, right: rightInset)
}
set {
topInset = newValue.top
leftInset = newValue.left
bottomInset = newValue.bottom
rightInset = newValue.right
}
}
override func sizeThatFits(_ size: CGSize) -> CGSize {
var adjSize = super.sizeThatFits(size)
adjSize.width += leftInset + rightInset
adjSize.height += topInset + bottomInset
return adjSize
}
override var intrinsicContentSize: CGSize {
let systemContentSize = super.intrinsicContentSize
let adjustSize = CGSize(width: systemContentSize.width + leftInset + rightInset, height: systemContentSize.height + topInset + bottomInset)
if adjustSize.width > preferredMaxLayoutWidth && preferredMaxLayoutWidth != 0 {
let constraintSize = CGSize(width: bounds.width - (leftInset + rightInset), height: .greatestFiniteMagnitude)
let newSize = super.sizeThatFits(constraintSize)
return CGSize(width: systemContentSize.width, height: ceil(newSize.height) + topInset + bottomInset)
} else {
return adjustSize
}
}
override func drawText(in rect: CGRect) {
super.drawText(in: rect.inset(by: insets))
}
}
其他回答
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
}
}
}
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。
斯威夫特 4+
class EdgeInsetLabel: UILabel {
var textInsets = UIEdgeInsets.zero {
didSet { invalidateIntrinsicContentSize() }
}
override func textRect(forBounds bounds: CGRect, limitedToNumberOfLines numberOfLines: Int) -> CGRect {
let textRect = super.textRect(forBounds: bounds, limitedToNumberOfLines: numberOfLines)
let invertedInsets = UIEdgeInsets(top: -textInsets.top,
left: -textInsets.left,
bottom: -textInsets.bottom,
right: -textInsets.right)
return textRect.inset(by: invertedInsets)
}
override func drawText(in rect: CGRect) {
super.drawText(in: rect.inset(by: textInsets))
}
}
用法:
let label = EdgeInsetLabel()
label.textInsets = UIEdgeInsets(top: 2, left: 6, bottom: 2, right: 6)
另一个没有子类化的选项是:
设置标签文本 sizeToFit () 然后稍微增加标签高度以模拟填充 标签。text = "someText" 标签。textAlignment = .center label.sizeToFit () label.frame = CGRect(x: label.frame.x, y: label.frame.y,width: label.frame.width + 20,height: label.frame.height + 8)
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.
