iOS之点击通知栏跳转应用的相关页面

当远程推送通知到达应用，有3个相关的方法是用来处理这个通知的。

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo
- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler 


在处理远程推送的情况下，这3个方法都干什么用的呢？请让我一一说来。
首先说说- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo 这个方法。为什么呢？因为它是推送到来的时候第一个调用的方法：
当推送消息到来的时候：
（1）如果应用处于运行状态，那么这个方法就会被调用，用来处理接收到的推送消息
（2）如果应用不在运行状态。这个方法就会启动应用，并且为应用提供相应的信息（这些信息放在启动项字典里------也就是application:willFinishLaunchingWithOptions: 或者application:didFinishLaunchingWithOptions: 的(NSDictionary *)launchOptions这个参数里）。但是这个方法并不会被应用调用来处理这个推送信息，应用会调用application:willFinishLaunchingWithOptions: 或者application:didFinishLaunchingWithOptions: 这两个方法来处理接收到推送消息。
 
接下来说说跟- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo相似的
- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler
其实
- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler
的作用跟- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo是一样的。两者的区别在于：（1）
- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo是iOS 3.0推出的，基于iOS 6.0 及以下的系统版本。而- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler则是在iOS 7.0推出的。基于iOS 7.0 及以上的系统版本。
（2）- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo只有在应用运行在前台的时候才会被调用。而- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler方法则无论应用运行在前台或者后台，在推送消息来到的时候都会被调用。
 
接下来说说- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
由前面的叙述可以知道，这个函数是在应用没有被启动的情况下，当推送消息到达的时候，由上述两个函数中的一个调用的。用来处理接收到推送消息。
 
最后，说说使用注意事项：
- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo 
和
- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler这两个函数都要实现。（如果这两个函数都实现，则应用会调用- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler）
 
最后的最后就是说说如何实现页面的跳转：
在上述两个函数里实现页面跳转：我这里的是：有一个TabBarController的单例，当推送到达，点击通知栏，跳转到第一个标签，并且第一个标签里面的数据要刷新
 
//接收到远程通知就会调用  点击横幅 就相当于接收新通知

- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo { 
[XTabBarControllershared].selectedIndex =0;
UINavigationController *navVC = [XTabBarControllershared].childViewControllers[0];
UIViewController *VC = navVC.viewControllers[0];
if([VCrespondsToSelector:@selector(refreshData)]){
[VCperformSelector:@selector(refreshData)];
}
// Required ----下面是极光推送的代码
[APServicehandleRemoteNotification:userInfo];
[selfactivePushMessage:application userInfo:userInfo];
}



- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler {    
    [XTabBarControllershared].selectedIndex =0;  
   UINavigationController *navVC = [XTabBarControllershared].childViewControllers[0];
   UIViewController *VC = navVC.viewControllers[0];
   if([VCrespondsToSelector:@selector(refreshData)]){
        [VCperformSelector:@selector(refreshData)];
    } 
   // iOS 7 Support Required  ---下面是极光推送的代码
    [APServicehandleRemoteNotification:userInfo];
    completionHandler(UIBackgroundFetchResultNewData);
    [selfactivePushMessage:application userInfo:userInfo];
}