has anyone gotten VIOP sockets to wake up the app on receipt of new data?
I have been able to do the following:
set plist flag to voip
set the streams as voip type
the sockets remain open when the application moves into the background but messages are not processed.
According to apple the correct behaviour is
" If new data arrives while your application is suspended, the system wakes up your application so that it can process the data. In the case of an incoming phone call, your application would typically alert the user immediately using a local notification. For other noncritical data, or if the user ignores the call, the system returns your application to the suspended state when it finishes processing the data."
anyone able to get that to work?
Are you setting the streams before opening them ?
It won't work unless you do so.
Related
While working with APNS, I was able to have push notifications work flawlessly while device is online.
For any APNS push I send while device is offline, only the last one is received once the device is back online. This seems to be coherent with Apple's Store-and-Forward design.
However - I did notice, that when sending WhatsApp messages to an offline device, once this device goes online it receives all push notifications (one for each message). This is not something based on collapse identifier, but rather independent push notification for each message.
So how did WhatsApp do it?
Tried using Notification Extension and attempt to post multiple local notifications, but this also fails as extensions are not allowed to do that.
Instead of a normal push notification, use a Background Notification, which will not show anything visible, but wake up your app in background. Use this event, to make api call, get relevant data and generate multiple local notifications.
Note the following from the documentation when you implement application(_:didReceiveRemoteNotification:fetchCompletionHandler:) :
system calls this method when your app is running in the foreground or background
system does not automatically launch your app if the user has force-quit it
you must call the block in the handler parameter (fetchCompletionHandler) or your app will be terminated. Your app
has up to 30 seconds of wall-clock time to process the notification
and call the specified completion handler block
Apps that use significant amounts of power when processing remote notifications may not always be woken up early to process future
notifications
Please read relevant documentation completely before making ANY assumptions about how you think this should work.
Maybe someone ever solve the problem with stable connection to server when application is in background? I need to transfer audio data from server to client app.
I know about all hacks for iOS how to keep alive application, but I need legal methods to solve this problem. Maybe you have any idea?
I found that I can send VoIP push to device that will wakeup my app and then establish tcp connect to my server but this socket will be keep alive about 30 seconds (as I see in log, every 3 seconds fires timer in iOS app that send data to server) this is not enough for me.
Maybe this project https://github.com/SmallSharpToolsOpenSource/Speakerbox will be helpful for someone.
And this video https://www.youtube.com/watch?v=lXJ1LDjL4Os
And official answer from Apple tech support:
PushKit is how voip apps can
reliable receive silent notifications, while CallKit is basically a UI
framework voip apps can use to notify the user about calls. Note that there
is NOT any direct connection within the APIs- for example, a voip app can
generate a local notification (instead of using CallKit) or simply do nothing
and “ignore” the notification entirely. Similarly, a voip app could “fake” a
call at anytime by simply telling CallKit that there was an incoming call (our
sample code for CallKit did exactly this).
Anything your app could previously have done when
it received voip socket traffic, it could also do when it received a PushKit
notification.
Standard voip apps
actually operate in two COMPETELY unrelated “modes”:
1) While waiting for an incoming call, the app is suspended until “something”
(PushKit OR a voip socket) wakes the app to tell it about the call.
2) Once a call has started, the app has an active audio session and is relying
an the standard “background audio” behavior of iOS, just like a wide variety
of other audio apps (for example, any streaming music app).
Is there any way to notify my video chat application that there is an incoming video call when the app is in the terminated state? (Like an Android background service.)
I notify of incoming calls via socket when the application is in the running and background states.
App that are using VoIP are treated differently by apple and have more privilieges. In the past, that meant keeping a permanent connection to the server to get notified when a call occurs.
This was not very efficient in terms of energy saving.
Since iOS8 it is recommanded to use PushKit (the push notification API) to notify your user when a call occurs. Apps with VoIP privileges will be notified on the spot and that can wake up your app whatever the state it's in.
Here are the world from apple :
Instead of persistent connections, developers should use the PushKit
framework—APIs that allows an app to receive pushes (notifications
when data is available) from a remote server. Whenever a push is
received, the app is called to action. For example, a VoIP app could
display an alert when a call is received, and provide an option to
accept or reject the call. It could even begin taking precursory steps
to initiate the call, in the event the user decides to accept.
https://developer.apple.com/library/ios/documentation/Performance/Conceptual/EnergyGuide-iOS/OptimizeVoIP.html
Get pushkit payload
Implement pushkit at ios code side
Once you receive silent notification
Schedule local notification
Keep important information in local notification's userinfo
Also keep local notification object in NSUserDefault
If your device gets restart then you can retrieve localnotification userinfo from NSUserDefault object
Once you get silent notification your socket will get active upto your local notification sound plays ( Max 30 seconds )
If you want incoming call ringing more than 30 seconds then server has to send silent notification at each 30 seconds
Delete previous object and reschedule latest on local notification
Let me know if you need any help in push kit implementation.
I was wondering how some existing apps refresh their application data while the app isn't running. Lets say we have a rain alarm application. This application send you a (local?) notification when its about to rain in your current location or location you've manually entered. What's the best way to achieve something like this?
Is the application getting weather data on the device itself (even when the application is killed) to send a local notification when its about to rain? Doesn't this method drains the battery of my device?
Or do I need to create a standalone application which runs 24/7 and always checks the weather? It then searches a database to see who's device needs a remote notification.
Other methods are also appreciated.
In iOS6 and before, your app cannot run all the time you want in the background, the system will stop the app after a few seconds.
A way that your example can be achieved is sending push notifications from a remote server.
Note: In iOS7 it will be possible to wake you app when a notification is received and download content.
Quick question, I am working on an APNS enabled app and I just want to know if there is a way that when the app is not open (not in background) and the app receives a remote notification;
Can I open the app in the background, unbeknownst to the the user, and do do what needs to be done.
I have looked at the docs but it doesnt explicitly say that this can or cannot be done (from what I read), it says that the user has to open the app manually (either from tapping an alert or the app icon).
I think it is clear what I'm looking to do however i'll put an example aswell.
Example)
The default Mail app alerts the user of new emails with a badge icon, showing the number of new emails, aswell as a sound. The user must then tap the app icon to open the app and download the new emails.
I want to be able to have the badge and sound but open the app in the background (silently) and download the new emails, so that when the user does get around to opening the app the emails will already be there, ready to read.
Thanks for any help.
unfortunately, what you describe is not possible.
the only way you could get something like that is to build a voip app. see the relevant section in this document.
Implementing a VoIP Application
A Voice over Internet Protocol (VoIP) application allows the user to make phone calls using an Internet connection instead of the device’s cellular service. Such an application needs to maintain a persistent network connection to its associated service so that it can receive incoming calls and other relevant data. Rather than keep VoIP applications awake all the time, the system allows them to be suspended and provides facilities for monitoring their sockets for them. When incoming traffic is detected, the system wakes up the VoIP application and returns control of its sockets to it.
anyway, I doubt that your app would get into the App Store, then...