小红点

一.系统自带

 [super viewDidLoad];

    // Do any additional setup after loading the view, typically from a nib.

    self.view.backgroundColor = [UIColor whiteColor];

    self.navigationItem.title = @"首页";

    UITabBarItem *item = [[UITabBarItem alloc]initWithTabBarSystemItem:UITabBarSystemItemBookmarks tag:1];

    self.tabBarItem = item;

    

//    NSArray *tabBarItems = self.navigationController.tabBarController.tabBar.items;

//    // 获取到需要展示消息的tabbarItem，属性badgeValue（标记个数）就是消息的条数

//    UITabBarItem *personCenterTabBarItem = [tabBarItems objectAtIndex:3];

//    personCenterTabBarItem.badgeValue = @"2"；//显示消息条数为 2

    item.badgeValue = @"99+";  

二.自定义

//    自定义方法：

//    自己将小红点图标放在想要显示的位置，控制UIImageView的hidden属性即可。实现思路如下：

    // 创建一个UIImageView，存放小红点图片

    UIImageView *dotImage = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"red_point_small"]];

    dotImage.backgroundColor = [UIColor redColor];

    // 获取tabbarItame的frame

    CGRect tabFrame =self.navigationController.tabBarController.tabBar.frame;

    CGFloat x =ceilf(0.5 * tabFrame.size.width);

    CGFloat y =ceilf(0.1 * tabFrame.size.height);

    // 设置小红点图标的frame

    dotImage.frame =CGRectMake(x, y, 8,8);

    // 将小红点imageView添加到tabbar上面

    [self.navigationController.tabBarController.tabBar addSubview:dotImage];

 

三.桌面icon图标红点

//获取用户授权

    if ([[UIDevice currentDevice].systemVersion floatValue] >= 8.0) {

        UIUserNotificationSettings *settings = [UIUserNotificationSettings settingsForTypes:UIUserNotificationTypeBadge categories:nil];

        [[UIApplication sharedApplication] registerUserNotificationSettings:settings];

    }

    //注册消息推送

    if ([[UIDevice currentDevice].systemVersion floatValue] >= 8.0) {

        UIUserNotificationSettings *settings = [UIUserNotificationSettings settingsForTypes:UIUserNotificationTypeBadge categories:nil];

        [[UIApplication sharedApplication] registerUserNotificationSettings:settings];

        [[UIApplication sharedApplication] registerForRemoteNotifications];

    }

    //设置推送消息个数

    [[UIApplication sharedApplication] setApplicationIconBadgeNumber:10];