ios 類似微信紅點顯示功能，ios類似顯示功能

ios 類似紅點顯示功能，ios類似顯示功能

設計思路：給UIView增加一個分類 所有的視圖都可以根據需要來進行紅點顯示

#import <UIKit/UIKit.h>@interface UIView (CHRRedDot)@property (readonly, nonatomic) CALayer * chr_redDotLayer;/** 紅點圓心的位置，與各個邊之間的距離。如果距離<=0，則忽略距離 */@property (nonatomic, assign) UIEdgeInsets chr_redDotEdgeInsets;/** 紅點的半徑，預設為4 */@property (nonatomic, assign) CGFloat chr_redDotRadius;/** 紅點的顏色，預設為0xFF5A5A */@property (nonatomic, strong) UIColor * chr_redDotColor;/** 紅點是否顯示 */@property (nonatomic, assign) BOOL chr_redDotShow;@end#pragma mark - method- (void)chr_updateRedDot {    CALayer *redDot = self.chr_redDotLayer;    if (self.chr_redDotShow) {        if (redDot == nil) {            redDot = [CALayer layer];            self.chr_redDotLayer = redDot;            [self.layer addSublayer:redDot];        }        redDot.backgroundColor = self.chr_redDotColor.CGColor;        [self chr_layoutRedDot];    } else {        [redDot removeFromSuperlayer];        self.chr_redDotLayer = nil;    }}- (void)chr_layoutRedDot {    CALayer *redDot = self.chr_redDotLayer;    if (redDot == nil) return;    CGFloat radius = self.chr_redDotRadius;    redDot.cornerRadius = radius;    UIEdgeInsets edgeInsets = self.chr_redDotEdgeInsets;    CGFloat originX = edgeInsets.right <= 0 ? edgeInsets.left - radius : self.bounds.size.width - edgeInsets.right + radius;    CGFloat originY = edgeInsets.bottom <= 0 ? edgeInsets.top - radius : self.bounds.size.height - edgeInsets.bottom + radius;    CGFloat length = radius * 2;    redDot.frame = CGRectMake(originX, originY, length, length);}