I’m trying to execute custom code that is invoked from a listprefeence radio box elsewhere in the setting UI. Its code that will allow the user to select different styles of battery icons on their phone on the fly without a reboot. I have everything done and the code executes fine with one exception. It takes 10-12 seconds for the change to take place. Kind of like it’s not executing until the system does its own check on battery status. How to I get it to execute immediately upon checking the box? Is this done through the use of a broadcast receiver? I am trying to learn android development and have become pretty good with smali but not so much with actual Java yet. I know it’s backwards but I’m trying….
Any help would be appreciated!
Thanks,
Jimmie
Not exactly broadcast receiver, what you want is to find out the system service which checks on battery status. As soon as the user request is received on the UI, you can call the system service to check on battery status and subsequently change the icon.
Also the system service you are looking for may not necessarily be the battery status checker service, it might be UI updater or some other updater service which runs after some time-out and reflects your change.
So you need to figure out which system service is reflecting your change, and then manually call that system service after user has changed his preferences.
Related
Search engines and Android developer website didn't help and I guess you can help with my problem.
I want to make an app for personal use, which is supposed to run all the time on my old tablet (powered all the time). The app will have several features requiring user interaction but independent of those, it should run a background job to check something continuously (real time!) for instance sound detection. It should also always try to connect another device on the network.
That means that job needs to run almost eternally without being killed. Some comments I have found suggested AlarmManager or BroadcastReceiver. But those are triggered by very defined triggers (either time or broadcast). I don't want that, because it should perform its task continuously all the time. This background job should also be able to communicate with the main Activity of my app to report what it is doing and allow user to interact with it (change settings of the job for instance).
Do you know any way how to accomplish this? Is IntentService correct choice for this (hoping that it won't get killed or maybe I should let the Activity to restart it?)
Thanks!
Do you know any way how to accomplish this?
Build your own custom ROM, with a modified version of Android that contains your code as a native Linux daemon.
Otherwise, what you want is technically impossible.
You can come fairly close by using a foreground Service (not an IntentService) and returning START_STICKY or START_REDELIVER_INTENT from onStartCommand(). Android may terminate your process from time to time, but it should restart your service automatically after a short while. That service can use its own background threads to do whatever it is that you are trying to do.
I did a search before asking so please don't tell me to do that.
I'm relatively new to Android so I get confused easily.
I'm making a simple app that changes the ringer volume according to time. For this purpose, I know I need a service that keeps running in the bg and monitor time. However, I really don't know how to approach this. I have the Professional Android Application Development book but haven't found anything that helps in there.
My question:
How to constantly check time without destroying the battery
If my code is needed (as proof of me actually working on this), I'll post.
You don't need a service. Use the AlarmManager class. Its like an alarm clock and it exactly what you need for this type of app.
need a service that keeps running in the bg and monitor time
No. Actually that's not how to do it. Services on android are different than your normal windows service/unix daemon. They should do their job and then stop themself until they get started again - to save battery.
You should start your service at a certain point in time by using the AlarmManager, it sends the launch intent to run the service. When the service is finished doing what it's supposed to do (change the rintone volume here), use Service.stopSelf() to kill it.
I want to create Event Reminder App, I search and found that I need to use a service and broadcast receiver.
But it is not clear for me what is the role of each components ?
As I understand-but I am not sure- that the App needs an Activity that when starts, it runs the service ( which check the current time with times are stored persistently , for example in database !). when the two times match , the service create a broadcast, and our broadcast receiver receives it and create Alert.
My questions are:
Does this inception is correct ?
How to make the service running and always check the time ( do we need some infinite loop?!!)
thanks in advance,
Activities and Services can be killed off without notice anytime system decides it's low on resources. There is no guarantee that your Service would run all the time. Also, if phone is in sleep mode, your code stops executing.
So:
The premise is wrong, for the reasons stated above.
You cant guarantee that Service would be running all the time.
For your purpose you should be using AlarmManager. It is garanteed to call your code when alarm is triggered. Also important - AlarmManager survives device restarts.
I have a question about Android application status. I want to know that am I able to check whether application is alive or dead, visible or on background. I need to make a decision according to application status in my broadcast receiver.
Thanks in advance..
You determine if your "application" is "alive" by seeing if the data you loaded in your "start up process" exists. If it does, use it. If it does not, run the "start up process".
Basically, when your receive broadcast your application is guaranteed to run. That's because broadcast can not be received without application process started first. And if there were no components active (like activities) when broadcast is sent, then application process is started for the sole purpose of processing this broadcast.
As for the other part, detecting if any Activity is currently active and/or visible - I haven't seen any API calls for this. There are might be some workaround (like manually keeping the counter in a singleton), but as far as I know there is no direct support for this. Though I might be wrong.
Within Android, it is standard practise to track 'changes' to the various states. You can read more about this here. Within the specific lifecycle related methods, you can perform specific actions as deemed appropriate.
I am coding an android application that gets the user position every 5 minutes, stores it in the database and sends it to a server.
I have read many ways of doing it, I was going to do the following:
User starts the application
The main UI activity starts a service.
The service runs in background and keeps turning on and off the gps, and creating new
threads that will save to database,and send the data to the server.
But I have seen that it can be done with a "Remote service" (http://developer.android.com/resources/samples/ApiDemos/src/com/example/android/apis/app/RemoteService.html) or with an AlarmManager that schedules starting this service every 5 minutes.
The service will need to be running always: it is important that after every interval (5 minutes), it is executed.
I think I need some clarity here.
Thank you for your help,
I am coding an android application that gets the user position every 5 minutes, stores it in the database and sends it to a server.
Please allow the user to choose the location provider. Not everybody has GPS on their device. Not everybody has GPS enabled. And, not everybody will want the power hit of GPS being turned on every five minutes.
Please allow the user to choose the polling period, including "never poll -- I'll refresh the information manually from the activity". Also, please honor the background data setting (deprecated as of ICS).
I think I need some clarity here.
If the polling is supposed to go on even if the activity is not in the foreground, use AlarmManager. However, most recipes for using AlarmManager will have the real work (in your case, GPS fix and network I/O) be handled by an IntentService. This will not work in your case, because GPS is asynchronous -- you cannot just get a fix whenever you feel like it. It will take a long time, possibly forever, to get a fix, so you have to deal with the delay and eventually timing out the operation. Writing a Service to do this is possible, but tricky, particularly if you are aiming to collect this information even if the device falls asleep.
If, however, the polling is only supposed to go on while the activity is in the foreground and the device is on, I wouldn't bother with a Service at all. Just have the activity use postDelayed() to set up an every-five-minutes scheduled bit of code to run, then have it do the work.