给 UITabBar 写个分类，搞定！
上代码:
// UITabBar+JHBadge.h
@interface UITabBar (JHBadge)
/// Show red dot.
- (void)jh_showRedDot:(NSInteger)index;
/// Hide red dot.
- (void)jh_hideRedDot:(NSInteger)index;
@end
// UITabBar+JHBadge.m
#import "UITabBar+JHBadge.h"
@implementation UITabBar (JHBadge)
- (void)jh_showRedDot:(NSInteger)index{
[[self reddotForIndex:index] setHidden:NO];
}
- (void)jh_hideRedDot:(NSInteger)index{
[[self reddotForIndex:index] setHidden:YES];
}
#pragma mark - private
- (UIView *)reddotForIndex:(NSInteger)index
{
NSInteger tag = 666 + index;
UIView *reddot = [self viewWithTag:tag];
if (!reddot) {
// If add custom button in 'Tabbar', 'count' should +1.
// 如果添加了自定义按钮，这里应该 +1.
NSInteger count = self.items.count;
CGFloat X = CGRectGetWidth(self.bounds)*((index+0.65)/count);
CGFloat Y = CGRectGetHeight(self.bounds)*0.1;
UIView *view = [[UIView alloc] init];
view.backgroundColor = [UIColor redColor];
view.layer.cornerRadius = 5;
view.tag = tag;
view.frame = CGRectMake(X, Y, 10, 10);
[self addSubview:view];
reddot = view;
}
return reddot;
}
@end
