1.ios设置角标个数的方法
方法1：
[[UIApplication sharedApplication] setApplicationIconBadgeNumber:99];
[[UIApplication sharedApplication] setApplicationIconBadgeNumber:count];
方法2：
[UIApplication sharedApplication].applicationIconBadgeNumber = 99
当角标个数为0的时候，设置个数为0，系统会自动设置角标不显示
2.角标设置之后不显示的原因
如果项目中集成了友盟的推送，那就是友盟推送默认清空角标，需要将默认清空关闭。调用此方法：
[UMessage setBadgeClear:NO];
3.需要提前设置权限
UIUserNotificationSettings *settings = [UIUserNotificationSettings settingsForTypes:UIUserNotificationTypeBadge categories:nil];
[[UIApplication sharedApplication] registerUserNotificationSettings:settings];
[application registerForRemoteNotifications];
if (@available(iOS 10.0, *)) {
UNUserNotificationCenter *center = [UNUserNotificationCenter currentNotificationCenter];
center.delegate = self;
[center requestAuthorizationWithOptions:(UNAuthorizationOptionBadge|UNAuthorizationOptionSound) completionHandler:^(BOOL granted, NSError * _Nullable error) {
if (!error) {
NSLog(@"请求权限成功!");
}
}];
[center getNotificationSettingsWithCompletionHandler:^(UNNotificationSettings * _Nonnull settings) {
NSLog(@"%@",settings);
}];
[[UIApplication sharedApplication] registerForRemoteNotifications];
} else {
// Fallback on earlier versions
}