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
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。
其他回答
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)
}
}
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。
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))
}
}
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。
Swift 3、iOS10解决方案:
open class UIInsetLabel: UILabel {
open var insets : UIEdgeInsets = UIEdgeInsets() {
didSet {
super.invalidateIntrinsicContentSize()
}
}
open override var intrinsicContentSize: CGSize {
var size = super.intrinsicContentSize
size.width += insets.left + insets.right
size.height += insets.top + insets.bottom
return size
}
override open func drawText(in rect: CGRect) {
return super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
}
}
