I am trying to make a chat app using XMPP protocol. The app is working fine except it doesn't show message notification when the app is in background. In Android I have used a Service for this purpose, however in Windows Phone I couldn't find anything similar to this.
I am trying Background Tasks for this, but as far as I have understood, they're made to run on prespecified trigger and I cannot add any custom trigger to it. In Android I have put my socket connection and parsing message calls in the service itself so that they can run on background too and the socket doesn't get closed even when the app is stopped.
So my question is, is there any similar way to do it in Windows Phone 8.1 (WinRT, not silverlight) or if Background Task is the only option, can you suggest a way to implement the notification functionality. I don't need the exact code, I just need a push to the right direction.
First: You cannot run a network connection in background.
Suggested way is using PushNotifications:
Either directly with a Toast Notification
Or with a PushTrigger to handle a Raw Notification, work out what to do
with it (who was it from, prepare data, etc.) and then create a ShellToast from it. Adds flexibility and improves user experience, but is quite complex.
Known downside: You have to use a server.
Only workarounds: Background-Tasks that checks for new messages about every 30 Minutes.
Related
I know that push notifications are being sent from a backend server. Is it possible to send notification from client itself? My application goes like this: It acquires its position using Location services API. once it enters a specific circle, the trigger calls a callback function. What i want to do is to use the callback function to push a notification to the device. Is there any way to do this?
Thank you very much in advance!
If you just want a notification when the app is active in the background, you can use local notifications: https://github.com/katzer/cordova-plugin-local-notifications. The plug-in Javascript has to be modified somewhat to work with a Worklight app, but with some simple modifications it works great, and allows your app running in the background to raise a notification without going through the server side round trip involved when using push.
That said, I implemented an app that did exactly what you are looking for (in my case, I needed some server side processing to figure out what the text of the push message should be) The geo-fence callback called an adapter, providing it with event details and the device ID. The adapter determined what message to send, and used unicast push to send it back to the device.
You can invoke a procedure in the client side. I tried to invoke in the client side with httpAdapter and its working.
If the notification doesn't need to come from the server, you can also create a service that will run in the background and show a dialogbox once it enters the geofence.
In Android, an app which is not currently running can be notified when certain event happens (like wifi scan results available, boot process completed) through Broadcast Receivers mechanism. Is this possible in anyway so that the wifi/geo triggers can be invoked even if the Worklight app is not running, including not running in the background?
Regarding wifi/connectivity changes notifying your app, that looks possible since it is a standard system event. It would likely take custom native code since you'd need to implement a broadcast receiver. And you'd need to register your receiver in your app's AndroidManifest.xml file. Take a look at http://developer.android.com/reference/android/net/ConnectivityManager.html and http://www.grokkingandroid.com/android-getting-notified-of-connectivity-changes/
Regarding geolocation triggers, it is unclear what sort of triggers you are looking for. This is all I see in the Android docs: http://developer.android.com/reference/android/location/GpsStatus.html and the standard broadcast actions at http://developer.android.com/reference/android/content/Intent.html#constants
If you are looking for something like geofencing, it would take application logic to determine when to fire events, so that means an app or service needs to be running. So although your broadcast receiver's onReceive() method can get called upon a geo event, who is going to fire that event?
Having the triggers activate when the application is not running at all (not even in background) isn't supported through the Worklight APIs.
You could try and use Worklight Android Native SDK together with cmarcelk's suggestions. Or you could use the Worklight Android triggers within a native service, together with the Broadcast Receivers mechanism so that it will run automatically on boot. You could then use an Intent to open the application from the trigger callback.
I have created a web-service app and i want to populate my view controllers according to the response i fetch(via GET) in main thread. But i want to create a scheduled timer which will go and control my server, if there becomes any difference(let's say if the count of an array has changed) i will create a local notification. As far as i read from here and some google results, i cant run my app in background more then ten minutes expect from some special situations(Audio, Vo-IP, GPS).. But i need to control the server at least one per minute.. Can anyone offer some idea-or link please?
EDIT
I will not sell the app in store, just for a local area network. Let's say, from the server i will send some text messages to the users and if a new message comes, the count of messages array will increment, in this situation i will create a notification. I need to keep this 'controlling' routing alive forever, whether in foreground or background. Does GCD give such a solution do anyone have any idea?
Just simply play a mute audio file in loop in the background, OR, ping the user's location in the background. Yes, that will drain the battery a bit, but it's a simple hack for in-home applications. Just remember to enable the background types in your Info.plist!
Note: "[...] I fetch (via GET) in main thread." This is not a good approach. You should never fetch any network resources on the main thread. Why? Because your GUI, which is maintained by the main thread, will become unresponsive whenever a fetch isn't instantaneous. Any lag spike on the network results in a less than desirable user experience.
Answer: Aside from the listed special situations, you can't run background apps. The way I see it:
Don't put the app in the background. (crappy solution)
Try putting another "entity" between the app and the "server". I don't know why you "need to control the server at least one per minute" but perhaps you can delegate this "control" to another process outside the device?
.
iOS app -> some form of proxy server -> server which requires
"babysitting" every minute.
I have a Web-Service application, i need to send scheduled GET methods to my server and if a change has happened with my incoming data i have to inform my user about the changes. When my app is in the foreground(in min thread) i fetch some data and pıpulate my tableview, my problem is, i can't realize how to create a scheduled method to the same data source(mean server) and if a new thing has been added, either my app is on bacground or not, inform user(alert) about the changes. Can anyone please share any idea-link.. Thanks in advance
This is exactly what push notifications were designed for, and are, technically the best way to solve the problem.
It does mean the task of 'checking' for new data is shifted to your server but the user is better suited as a push notification will happen, even if your app is not running.
I recommend using a system like Urban Airship.
I started off on the Win8 metro app (javascript) development recently. For notifications, it is clear how the WNS notifications will be useful for creating live tiles.
However the use case for local notifications is not clear to me. I have these two questions:
is it correct to assume local notifications make sense only for apps that would run in the background e.g. when other apps are running or when the system is locked?
if the above is not true, then kindly suggest some examples of when local notifications will be useful.
regards
CGere
Local notifications are useful to update your tile on the start screen that persist after your app was closed/suspended. For example you might want to update the tile when your app closes with some context, perhaps an image from the last level of the game they were on or such.
When your app goes to the background it has a short period of time to suspend after which your app will no longer be running and thus unable o update the tile. You can however create a background task to run on an event/timer to do some work (such as update your tile).