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Question

In an iOS app using remote notifications (coming from Parse.com) I have the following issue: While it is often appreciated to see a little note telling the user that something new has arrived, there are also times when silence is much more appreciated. Knowing that the app is doing its job as it should (in the background), without being told about every single event is what we want.

How can I achieve that?

Browsing the net I've read about UIBackgroundModes in Info.plist; but when I tried I didn't get the result I was hoping for. I guess I must either be using the wrong tool or missusing it. I've also read that Apple may be picky about the usage of these UIBackgroundModes when reviewing apps. So I may as well avoid looking for trouble if possible.

To avoid misunderstanding I put the code below, which is working; except for the fact that it is "noisy". Meaning the app is happy to receive notifications (and this works); but the user would be happy not to know about it, meaning not to see "ABC" on the phone all the time.

On the cloud:

function pushNotification()
{
    var pushQuery = new Parse.Query(Parse.Installation);
    pushQuery.equalTo(‘fieldXZY’, 'ios');

    Parse.Push.send({
                    where: pushQuery,
                    data: {
                    alert: “ABC"
                    }
                    }, {
                    success: function() {},
                    error: function(error) {
                    throw "Got an error " + error.code + " : " + error.message;
                    }
                    });
}

Inside the app:

- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo
{
    NSString *notifString=[[userInfo valueForKey:@"aps"] valueForKey:@"alert"];

    if ([notifString isEqualToString:@“ABC"]) // The Notification has come.
        [self doTheWorkForABCNotif];
}

Answer 1

Don't send sound key in aps if you want no voice for receiving notification. aps should be similar as below

aps = {
  alert = "You have received a message";
  badge = 3;
  "content-available" : 1,// this key will allow to receive payload data even if app is in background
};

remove alert also if you don't want to show alert . do what ever you want in custom payload keys

Answer 2

As far as I know, there is no api to disable the push notification sound in native code. The user may disable or enable it through Settings->Notifications->your app

However I suppose it is possible to achieve this with custom sound specification. Check this apple doc if you don't know. To do this, put an custom sound file which contains no sounds at all. And then, if you don't want the user to receive the sound, just specify the sound file in the JSON payload before you send it to Apple Push Notification Service

Answer 3

Silent notifications are mighty useful if you want to trigger something in the app (like a background fetch, data clearing in the database, updating sync dates etc.) To successfully achieve this you will need three things

1) Background modes

In your app's Info.plist , you need to add App downloads content in response to push notifications as one of the Required background modes

2) Delegate callback

In your app delegate you need to implement

 - (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler{
// Do your stuff here 
}

Note the additional

fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler

block in the callback

and also implement

-(void)application:(UIApplication *)application performFetchWithCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler{
// Run your background fetch here
}

3) Notification Payload

The payload needs to be in the following structure (in addition to any custom payload)

 {
        "aps" : {
            "content-available" : 1,
            "sound" : ""
        }
        "customPayloadKey":3,
        "additionalPayload": {
                               "customKey":"customValue"
                             }
    }

Cheers !

Answer 4

If you are using Parse, they have an option to send in message via JSON format.

For example : {"message":"Hello World","badge":"1","sound":"silent.mp3"}

You can add an audio file to your app bundle which goes by the name of silent.mp3. This audio file could be just an empty recorded audio.

However, this would require you to update your app to the store as you have to add an audio file to your bundle.When you send in the above JSON, it would try to find the audio file named silent.mp3 in your app bundle and play that file as notification sound.

Since, the audio file is just a silent recording, there won't be any notification sound. You may add various audio files to your bundle and control it via Parse when you send in the Push Notification.

I hope this provides you with a workaround solution.