I have been given multiple solutions to what I thought would be a common scenario. Unfortunately, none seem to work as expected.
I have created a pretty simple android game. The users can invite friends to play and there are a few activities they are routed through during the game lifecycle. All turns and data is stored in a remote server which is exposing the data through web services. Every time an invitation is sent, or the opponents complete their turn, the user is prompted via the service to play their turn.
The service prompts the user using a standard android notification telling them it's their turn. I don't want the service to poll the web service or present notifications while the user is viewing the game (they'll already know if it's there turn).
I have tried the following solutions without any success.
Start the service in the onPause method of the main activity and stop the service in the onResume method of the main activity.
Problem - Each time the user leaves the activity for another one the service starts. The user may be writing something or creating an invitation and they are prompted to take their turn.
Bind each activity to the service and set a boolean (running) flag in the same onPause/onResume methods of all activities.
Problem - This seems logical, but for some reason the service never presents a notification. This is likely user-error, but I'm not sure this is the correct solution anyway.
Start the service in the onPause method of all activities and stop the service in the onResume method of all activities.
Problem - Based on the toasts I'm presenting on the screen showing the state of the service this works as expected. The problem is the user is presented with notifications while the service is off. Apparently my toasts are misleading.
Any help is greatly appreciated. Sample code is not necessary, but would be appreciated if the solution is any more complex than the concept described above.
Thank you.
Don't use a service, use the Google Cloud Messaging and in the receiver of the broadcast, check the state of the game and then decide whether or not to show the notification. Polling is generally bad, uses data and battery unnecessarily.
Related
I know this look like tons of question around SO. But it's not (although I can also be wrong).
I have a long running Service (running in a separate thread using blutooth socket pooling for data in a OBD2 adapter every 5 seconds).
This Service is running in the same process and is a Foreground Service.
The user start this Service through an Activity. It then connect to the Bluetooth device and start pooling and saving data to a SQLiteDataBase.
The user can then minimize the activity and do other stuff.
When he returns (if ever, he can stop the service through a notification area button) to the application it checks if the Service is running and if so, it starts another Activity which show the data that is being pulled from the OBD2.
My question is, between this visualization Activity and the Service should I use and by this I mean the recommended or the right one:
LocalBroadcast? This is actually what I am using. Every time the service pull some data, it sends a broadcast with the data everytime it was pulled. Then in the onReceive method call runOnUiThread to update the respective View.
Messenger? As far as I know (never used it) I should send a Messenger from the Activity to the Service (much like a Handler) and in the Service it should send the Messages with the data pulled. But from this I would get a RemoteObjectException if the Activity was destroyed (like I said, the user could just minimized the activity and then it got GCed). So, I would probably need a way of sending the Messenger to the Service every time the Activity gets created and check if it's ok to use the messenger form the Service every time (if that's even possible, I've never used this).
BindService? Should I bind to the service when I open the Activity and then get the data directly from methods in the Service? But this would probably mean I would have another thread in the Activity gets this data from the Service every time, right?
Handler? (for a moment now I realize don't know the difference between Messenger and Handler, should it be that "use Messenger when Service runs in another process and Handler otherwise)
I've seen/read a lot of answers here in SO and through the web in general.
But in the end I don't see a ultimate answer for my case. But I'm sorry if this is just because I couldn't figure it out.
Thanks in advance!
EDIT: forgot to mention, I would rather make use only support libraries and android framework stuff, I'm still learning Android and I want to understand what's happening within its own classes.
In my application I check to the server some user state in the onCreate() method of the main activity.
I recently notice that doing so is an issue when I run the app from Eclipse while the phone is asleep (screen off, locked). In this situation, the application waits that the screen get unlocked to call the onStart() method and pursue its way. That makes fail the data update.
Maybe I should put it inside onStart?
Can the user do the same process = start an app with locked screen? I though of Tasker but are there other way?
Edit: All the server updates communication are done off main thread, handled by managing classes and I use volley. So it's not a service and though I will put one later, I have not enough time to do it now. Except if you say it's 2 days work to learn and implement. Can a user start an application like a dev can do it ?
This things that you are doing in an Activity must surely be performed in a Service. Android Service provides you with doing background data processing/syncing.
I am currently in the process of writing a music app. Having read around the subject a bit its time to start writing a service and interfacing to it from my main activity. The Google Dec docs seem to indicate that the main activity should for the heavy lifting and the service should be streamlined as much as possible. My main activity does quite a lot of work to maintain a play list of songs. I've been trying (Without success) to pass that play list over to the service when the user clicks play. However, I'm now wondering if I need to do that.
My thinking is that I could let the main activity create the playlist. When user clicks play it sends the first track path, using a string, to the service which handles playing. The service also has the oncomplete listener. When it triggers it sends a broadcast back to the activity. When the broadcast is received it would launch the "next" function, which throws the next track to the service.
Would this work in theory?
I've worked it out for myself. For those that are interested my theory works perfectly. The activity handles the play, next, prev etc and playlists. The service receives instructions from the activity, and requests new instruction via broadcasts.
I have a thread (Updater) inside a service (RefreshTasks) that check if there are some updates on the server. Then I have 4 activities that use those data.
But I have a problem in managing this service...
I would like to keep the service active along the whole application, even if the screen goes off. What is the correct practice to manage a service like this? In this moment I start and stop the service every onResume and onPause method of all activities... but this implies that the service will stop when the screen goes off.
Any suggestion?
Thanks AL.
The Service instance continues to run also when your app is paused.
I suggest you to look also this service provided by Google, which is a good solution for push notification in communication between the device and your service:
https://developers.google.com/android/c2dm/
And this is a good tutorial to start with:
http://blog.mediarain.com/2011/03/simple-google-android-c2dm-tutorial-push-notifications-for-android/
I am making an android app which will have two services that will keep sending data about the usage of the phone by the user every 24 hours.
The user should execute the app, toggle the buttons to enable the logging of the usage of the phone and then the user should be able to do a normal life with his phone, until he starts again the app and disables the toggle button to stop the logging of the info.
What considerations should I take about the life cycle of the services?
What about the interaction of the user with the phone while the services should be sending the data?
All info is very much appreciated, as I my mind is getting a little bit overwhelmed with all this!
Thanks a lot in advance everybody!
The service can be cut at any time through the settings menu. It can also be killed at any time by Android if it decides it needs the resources for the currently running activity. onDestroy() will be called regardless so use that to store anything needed.
The service runs in the background but through the main UI thread. Thus, it is possible to block operation of the phone through a service. It looks like the phone locked up when it's really a service trying to do something. Any blocking procedure should be used in a thread such as Java timer, Java thread, or AsyncTask.
There can only be one running version of the service at any given time. However, calling startService(myService) if "myService" is already running will essentially override the current running service and onStartCommand() will be called again. However, one call to stopService(myService) is needed to stop it no matter how many times startService(myService) was called.
stopService(myService) will not stop a service if the service is bound to anything. It will wait until all bindings are removed before the service stops.