iOS开发之旅--本地通知的发送与取消

现在有时间，就把之前学习的使用过的本地通知的基本过程给大家分享一下。

解释一下本地通知是程序员在应用中给用户手动推送的消息。（与远程推送的具体区别，后期会更新。）

本地通知的具体实现如下：

首先， 我创建了一个本地通知的Demo：AmerLocationNotification：

在Main.storyboard中拖一个switch并脱线出Change事件：

接下来，我们要将具体实现写在该事件中。

- (IBAction)changed:(UISwitch *)sender
{
UIApplication *app = [UIApplication sharedApplication];

if (sender.on)
{
// 初始化本地通知对象
UILocalNotification *notification = [[UILocalNotification alloc] init];

if (notification)
{
// 使用本地时区
notification.timeZone = [NSTimeZone defaultTimeZone];

//设置出发时间
notification.fireDate = [NSDate dateWithTimeIntervalSinceNow:10.0];

// 设置重复间隔
notification.repeatInterval = kCFCalendarUnitMinute;

// 设置锁屏时，提醒文字title
notification.alertAction = @"查水表";

// 设置提醒的文字内容
notification.alertBody   = @"你妈妈叫你回家吃饭";

// 通知提示音 使用默认的
notification.soundName= UILocalNotificationDefaultSoundName;

// 设置应用程序右上角的提醒个数
notification.applicationIconBadgeNumber = 1;

// 设定通知的userInfo，用来标识该通知
NSDictionary *infor = @{@"amer.org" : @"key"};

notification.userInfo = infor;

/*这里也可以设置alertLaunchImage*/

// 将通知添加到系统中
[app scheduleLocalNotification:notification];
}
}
else
{
//获取所有除与调度中的数组
NSArray *locationArr = app.scheduledLocalNotifications;
if (locationArr)
{
for (UILocalNotification *ln in locationArr)
{
NSDictionary *dict =  ln.userInfo;

if (dict)
{
NSString *obj = [dict objectForKey:@"amer.org"];

if ([obj isEqualToString:@"key"])
{
//取消调度通知
[app cancelLocalNotification:ln];
}
}
}
}
}
}

注意：这种状态的通知，是只有你的应用进入后台才会有提示。

else中得代码是要取消通知，一定要实现，否则你会被不停的通知烦死。因为如果你不取消通知，即使你将应用卸载重装，通知依旧存在，仍然会给你弹。

下一步，我们要实现让通知在应用在前台显示时也可以提醒,代码位于appDelegate中.

-(void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notification
{
    NSLog(@"接收到通知");
    
    [[[UIAlertView alloc] initWithTitle:notification.alertAction
                               message:notification.alertBody
                              delegate:nil
                     cancelButtonTitle:@"确定"
                     otherButtonTitles:nil] show];
    
    application.applicationIconBadgeNumber = 0;
}

- (void)applicationWillEnterForeground:(UIApplication *)application
{
    //如果app在前台运行
    application.applicationIconBadgeNumber = 0;
}

最后最重要的一步，千万不要漏掉，否则你什么通知也收不到。

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    
    UIApplication *app = [UIApplication sharedApplication];
    //是否响应registerUserNotificationSettings（ios8以后）
    if ([app respondsToSelector:@selector(registerUserNotificationSettings:)])
    {
        UIUserNotificationSettings *settings = [UIUserNotificationSettings
                                                settingsForTypes:UIUserNotificationTypeBadge|UIUserNotificationTypeSound|UIUserNotificationTypeAlert categories:nil];
        
        [app registerUserNotificationSettings:settings];
    }
    else       //如果不适配iOS8之前的设备，这个else可以省略
    {
        UIRemoteNotificationType myTypes = UIRemoteNotificationTypeBadge |
                                           UIRemoteNotificationTypeAlert |
                                           UIRemoteNotificationTypeSound;
        
        [app registerForRemoteNotificationTypes:myTypes];
    }
    return YES;
}
-(void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notification{
    
    [application registerForRemoteNotifications]; // <================== 新添加
    
    NSLog(@"接收到通知");
    
    [[[UIAlertView alloc] initWithTitle:notification.alertAction
                               message:notification.alertBody
                              delegate:nil
                     cancelButtonTitle:@"确定"
                     otherButtonTitles:nil] show];
    
    application.applicationIconBadgeNumber = 0;
}

文档原话：

// In iOS 8.0 and later, your application must register for user notifications using -[UIApplication registerUserNotificationSettings:]
 before being able to schedule and present UILocalNotifications