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
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
}
}
其他回答
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。
斯威夫特5
在layoutSubviews()方法上，更改UILabel的插入，如下所示。
override func layoutSubviews() {
super.layoutSubviews()
label.frame = label.frame.inset(by: UIEdgeInsets(top: 5, left: 10, bottom: 5, right: 10))
}
如果你不想或需要在Storyboard中使用@IBInspectable / @IBDesignable UILabel(我认为那些渲染太慢了)，那么使用UIEdgeInsets而不是4个不同的cgfloat会更干净。
Swift 4.2的代码示例:
class UIPaddedLabel: UILabel {
var padding = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
public override func drawText(in rect: CGRect) {
super.drawText(in: rect.inset(by: padding))
}
public override var intrinsicContentSize: CGSize {
let size = super.intrinsicContentSize
return CGSize(width: size.width + padding.left + padding.right,
height: size.height + padding.top + padding.bottom)
}
}
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))
}
}
