实现原理：
其实是自定义一个view，将view添加到UITabBar上面，也可以是一个按钮，设置背景图片，和label。
废话少说直接上代码
搞一个UITabBar的分类
#import <UIKit/UIKit.h> @interface UITabBar (badge) - (void)showBadgeOnItemIndex:(int)index;
- (void)hideBadgeOnItemIndex:(int)index; @end
#import "UITabBar+badge.h" #define TabbarItemNums 5.0 @implementation UITabBar (badge) // 显示红点
- (void)showBadgeOnItemIndex:(int)index { [self removeBadgeOnItemIndex:index];
// 新建小红点
UIView *bview = [[UIView alloc]init];
bview.tag = 888 + index;
bview.layer.cornerRadius = ;
bview.clipsToBounds = YES;
bview.backgroundColor = [UIColor redColor];
CGRect tabFram = self.frame; float percentX = (index+0.6) / TabbarItemNums;
CGFloat x = ceilf(percentX * tabFram.size.width);
CGFloat y = ceilf(0.1 * tabFram.size.height);
bview.frame = CGRectMake(x, y, , );
[self addSubview:bview];
[self bringSubviewToFront:bview];
} // 隐藏红点
- (void)hideBadgeOnItemIndex:(int)index { [self removeBadgeOnItemIndex:index];
}
// 移除控件
- (void)removeBadgeOnItemIndex:(int)index { for (UIView *subView in self.subviews) {
if (subView.tag == 888 + index) {
[subView removeFromSuperview];
}
}
}
@end
最后在子控制器调用就可以啦
#import "UITabBar+badge.h" [self.tabBarController.tabBar showBadgeOnItemIndex:];
swift版带消息个数
import UIKit
extension UITabBar {
func showBadgeOnItem(index:Int, count:Int) {
removeBadgeOnItem(index: index)
let bview = UIView.init()
bview.tag = +index
bview.layer.cornerRadius =
bview.clipsToBounds = true
bview.backgroundColor = UIColor.red
let tabFrame = self.frame
let percentX = (Float(index)+0.6) / 5.0(tabBar的总个数)
let x = CGFloat(ceilf(percentX*Float(tabFrame.width)))
let y = CGFloat(ceilf(0.1*Float(tabFrame.height)))
bview.frame = CGRect(x: x, y: y, width: , height: )
let cLabel = UILabel.init()
cLabel.text = "\(count)"
cLabel.frame = CGRect(x: , y: , width: , height: )
cLabel.font = UIFont.systemFont(ofSize: )
cLabel.textColor = UIColor.white
cLabel.textAlignment = .center
bview.addSubview(cLabel)
addSubview(bview)
bringSubview(toFront: bview)
}
// 隐藏红点
func hideBadgeOnItem(index:Int) {
removeBadgeOnItem(index: index)
}
// 移除控件
func removeBadgeOnItem(index:Int) {
for subView:UIView in subviews {
if subView.tag == +index {
subView.removeFromSuperview()
}
}
}
}