我按照这个教程 https://developers.google.com/cloud-messaging/ios/client 实现了在我的 iOS 应用程序中使用 GCM。我的应用服务器是使用 Java 编写的 Google App Engine，我使用了 gcm-server.jar 库 https://github.com/google/gcm。我认为我的证书没问题，我可以注册、获取令牌，甚至接收由我的应用服务器发送的消息内容。但是，当应用程序处于后台时，我不会收到任何通知提醒，只有当我点击应用程序图标重新启动它时才会收到通知。
我以为这是因为我只实现了
我以为这是因为我只实现了
didReceiveRemoteNotification: 而没有实现 didReceiveRemoteNotification:fetchCompletionHandler: ，所以我改为使用后者进行实现，但是当应用程序在后台时，我仍然无法收到通知，更糟糕的是，应用程序会崩溃，提示类似“未识别的选择器发送到实例 didReceiveRemoteNotification:”之类的错误，好像 userInfo 中出现了一些问题。我已经在 xCode 中允许了后台模式，代码如下：AppDelegate ()
@property (nonatomic, strong) NSDictionary *registrationOptions;
@property (nonatomic, strong) GGLInstanceIDTokenHandler registrationHandler;
@end
@implementation AppDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
//-- Set Notification
[[GCMService sharedInstance] startWithConfig:[GCMConfig defaultConfig]];
if ([application respondsToSelector:@selector(isRegisteredForRemoteNotifications)])
{
NSLog(@"Case iOS8");
// iOS 8 Notifications
[application registerUserNotificationSettings:[UIUserNotificationSettings settingsForTypes:(UIUserNotificationTypeSound | UIUserNotificationTypeAlert | UIUserNotificationTypeBadge) categories:nil]];
[application registerForRemoteNotifications];
}
else
{
NSLog(@"Case iOS7");
// iOS < 8 Notifications
[application registerForRemoteNotificationTypes:
(UIRemoteNotificationTypeBadge | UIRemoteNotificationTypeAlert | UIRemoteNotificationTypeSound)];
}
self.registrationHandler = ^(NSString *registrationToken, NSError *error){
if (registrationToken != nil) {
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setObject:registrationToken forKey:TOKENGCM];
NSLog(@"Registration Token: %@", registrationToken);
//some code
} else {
NSLog(@"Registration to GCM failed with error: %@", error.localizedDescription);
}
};
return YES;
}
- (void)applicationWillResignActive:(UIApplication *)application {
}
- (void)applicationDidEnterBackground:(UIApplication *)application {
[[GCMService sharedInstance] disconnect];
}
- (void)applicationWillEnterForeground:(UIApplication *)application {
}
- (void)applicationDidBecomeActive:(UIApplication *)application {
// Connect to the GCM server to receive non-APNS notifications
[[GCMService sharedInstance] connectWithHandler:^(NSError *error) {
if (error) {
NSLog(@"Could not connect to GCM: %@", error.localizedDescription);
} else {
NSLog(@"Connected to GCM");
// ...
}
}];
}
- (void)applicationWillTerminate:(UIApplication *)application {
}
- (void)application:(UIApplication *)application
didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken {
// Start the GGLInstanceID shared instance with the default config and request a registration
// token to enable reception of notifications
[[GGLInstanceID sharedInstance] startWithConfig:[GGLInstanceIDConfig defaultConfig]];
self.registrationOptions = @{kGGLInstanceIDRegisterAPNSOption:deviceToken,
kGGLInstanceIDAPNSServerTypeSandboxOption:@NO};
[[GGLInstanceID sharedInstance] tokenWithAuthorizedEntity:SENDER_ID
scope:kGGLInstanceIDScopeGCM
options:self.registrationOptions
handler:self.registrationHandler];
}
- (void)application:(UIApplication *)app didFailToRegisterForRemoteNotificationsWithError:(NSError *)err {
NSLog(@"Error in registration. Error: %@", err);
}
- (void)onTokenRefresh {
// A rotation of the registration tokens is happening, so the app needs to request a new token.
NSLog(@"The GCM registration token needs to be changed.");
[[GGLInstanceID sharedInstance] tokenWithAuthorizedEntity:SENDER_ID
scope:kGGLInstanceIDScopeGCM
options:self.registrationOptions
handler:self.registrationHandler];
}
- (void)application:(UIApplication *)application
didReceiveRemoteNotification:(NSDictionary *)userInfo {
NSLog(@"Notification received: %@", userInfo);//This does print the content of my message in the console if the app is in foreground
UIApplicationState state = [application applicationState];
if (state == UIApplicationStateActive) {
NSString *cancelTitle = @"Close";
NSString *showTitle = @"Show";
NSString *message = [[userInfo valueForKey:@"aps"] valueForKey:@"alert"];
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"Some title"
message:message
delegate:self
cancelButtonTitle:cancelTitle
otherButtonTitles:showTitle, nil];
[alertView show];
}
else{
NSLog(@"Notification received while inactive");
[[UIApplication sharedApplication] setApplicationIconBadgeNumber: 99];
UIAlertView *BOOM = [[UIAlertView alloc] initWithTitle:@"BOOM"
message:@"app was INACTIVE"
delegate:self
cancelButtonTitle:@"a-ha!"
otherButtonTitles:nil];
[BOOM show];
NSLog(@"App was NOT ACTIVE");
[[NSNotificationCenter defaultCenter] postNotificationName:@"Notification!"
object:nil
userInfo:userInfo];
}
// This works only if the app started the GCM service
[[GCMService sharedInstance] appDidReceiveMessage:userInfo];
}
//Implement that causes unrecognized selector crash
- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))handler {
NSLog(@"Notification received: %@", userInfo);
// This works only if the app started the GCM service
[[GCMService sharedInstance] appDidReceiveMessage:userInfo];
// Handle the received message
// Invoke the completion handler passing the appropriate UIBackgroundFetchResult value
// [START_EXCLUDE]
[[NSNotificationCenter defaultCenter] postNotificationName:@"notif"
object:nil
userInfo:userInfo];
handler(UIBackgroundFetchResultNoData);
// [END_EXCLUDE]
}
@end
有人能够解决我在不在前台时为什么无法收到通知的问题吗？
编辑：用于发送GCM消息的服务器端Java代码：
public static MulticastResult sendViaGCM(String tag, String message, List<String> deviceIdsList) throws IOException {
Sender sender = new Sender(Constantes.API_KEY);
// This message object is a Google Cloud Messaging object
Message msg = new Message.Builder().addData("tag",tag).addData("message", message).build();
MulticastResult result = sender.send(msg, deviceIdsList, 5);
return result;
}
public static void sendGCMMessage(String tag, String message, List<String> deviceIdsList) {
String request = "https://gcm-http.googleapis.com/gcm/send";
try{
URL url = new URL(request);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setDoOutput(true);
//conn.setInstanceFollowRedirects(false);
conn.setRequestMethod("POST");
//Les deux headers obligatoires:
conn.setRequestProperty("Content-Type", "application/json");
conn.setRequestProperty("Authorization", "key=" + API_KEY);
//Construction du JSON:
JSONObject fullJSON = new JSONObject();
JSONObject data=new JSONObject();
JSONObject notification=new JSONObject();
data.put("tag", tag);
data.put("message", message);
notification.put("sound", "default");
notification.put("badge", "1");
notification.put("title", "default");
notification.put("body", message);
fullJSON.put("registration_ids", deviceIdsList);
fullJSON.put("notification", notification);
fullJSON.put("content_available", "true");
fullJSON.put("data", data);
//Phase finale:
OutputStreamWriter wr= new OutputStreamWriter(conn.getOutputStream());
wr.write(fullJSON.toString());
wr.flush();
wr.close();//pas obligatoire
//conn.setUseCaches(false);
}
catch(Exception e){
e.printStackTrace();
}
self.registrationOptions = @{kGGLInstanceIDRegisterAPNSOption:deviceToken, kGGLInstanceIDAPNSServerTypeSandboxOption:@NO};中的“NO”更改为“YES”，最终在后台接收到了消息。现在，我只需要按照您建议的在Java示例中进行更改，但问题是我只有一个JAR文件，因此无法访问Message类并对其进行修改。请问我该如何执行这个操作？ - Gannicus