系统的UILabel附上文字后后自动给出一定的内边距,按照UI的设计图需求,标签附着文字后不能留有边距,只能自己自定义一个没有内边距的UILabel。
OC版本
#import <UIKit/UIKit.h>
IB_DESIGNABLE
@interface InsetLabel : UILabel
@property (nonatomic, assign) IBInspectable CGFloat leftEdge;
@property (nonatomic, assign) IBInspectable CGFloat rightEdge;
@property (nonatomic, assign) IBInspectable CGFloat topEdge;
@property (nonatomic, assign) IBInspectable CGFloat bottomEdge;
@property (nonatomic, assign) UIEdgeInsets edgeInsets;
@end
#import "InsetLabel.h"
@implementation InsetLabel
- (id)initWithFrame:(CGRect)frame {
self = [super initWithFrame:frame];
if (self) {
self.edgeInsets = UIEdgeInsetsMake(self.topEdge, self.leftEdge, self.bottomEdge, self.rightEdge);
}
return self;
}
// 文字区域
- (void)drawTextInRect:(CGRect)rect {
self.edgeInsets = UIEdgeInsetsMake(self.topEdge, self.leftEdge, self.bottomEdge, self.rightEdge);
[super drawTextInRect:UIEdgeInsetsInsetRect(rect, self.edgeInsets)];
}
// UILabel的内容区域
- (CGSize)intrinsicContentSize {
self.edgeInsets = UIEdgeInsetsMake(self.topEdge, self.leftEdge, self.bottomEdge, self.rightEdge);
CGSize size = [super intrinsicContentSize];
size.width += self.edgeInsets.left + self.edgeInsets.right;
size.height += self.edgeInsets.top + self.edgeInsets.bottom;
return size;
}
@end
swift版本
class UILabelPadding : UILabel {
private var padding = UIEdgeInsetsZero
@IBInspectable
var paddingLeft: CGFloat {
get { return padding.left }
set { padding.left = newValue }
}
@IBInspectable
var paddingRight: CGFloat {
get { return padding.right }
set { padding.right = newValue }
}
@IBInspectable
var paddingTop: CGFloat {
get { return padding.top }
set { padding.top = newValue }
}
@IBInspectable
var paddingBottom: CGFloat {
get { return padding.bottom }
set { padding.bottom = newValue }
}
// 文字区域
override func drawTextInRect(rect: CGRect) {
super.drawTextInRect(UIEdgeInsetsInsetRect(rect, padding))
}
// UILabel的内容区域
override func textRectForBounds(bounds: CGRect, limitedToNumberOfLines numberOfLines: Int) -> CGRect {
let insets = self.padding
var rect = super.textRectForBounds(UIEdgeInsetsInsetRect(bounds, insets), limitedToNumberOfLines: numberOfLines)
rect.origin.x -= insets.left
rect.origin.y -= insets.top
rect.size.width += (insets.left + insets.right)
rect.size.height += (insets.top + insets.bottom)
return rect
}
}