I have a service in my app along with activity classes. I want to start service as soon as app is installed. I have been able to start service on app launch,on device reboot, but not on app install.
Any idea if it is possible and if possible then how it can be done?
Thanks in advance.
Any idea if it is possible
Upon installation, your app is in the so-called "stopped state" and will remain there until something uses an explicit Intent to start up one of your components. Unless your app is a plugin for some other app that will do this, your app will not run until the user taps on the home screen launcher icon associated with one of your activities.
Related
I have to develop an Android App that starts a service on boot. I have the privilege of creating even a new service in framework for it. But before that I have two question so this might be possible without going to framework.
Can an app (service only) signed with system keys be launched without an app launcher and start on boot without any activity ?
This is really another way of asking the first question : Can an app signed with system keys start for the very first time with BOOT COMPLETED broadcast intent ? I am aware that this is not possible for apps in user app space
Further documentation on the topic can be found here
In an interview recently, the interview asked if it is possible to start service after just installing the app without starting it?
Is it possible to do?
It is not supposed to be possible.
Apps are installed in a "stopped state", the same state that they are in after the user presses "Force Stop" on the app's page in Settings. While in that "stopped state", it takes an explicit Intent to cause any of that app's code to run. In most apps, that means that the user taps the home screen launcher icon for the app.
Yes you can. I don't know if it is enough with the receiver android.intent.action.PACKAGE_INSTALL because I always thought that was related to other app installs. But you can capture the BOOT event, or the connectivity change event or something like that to start a service or whatever you want.
If I'm writing my own Android app, I know how to structure it as a Service so it will start running in the background.
However, is there a way to launch an existing app (for example, any random .apk from the Play Store) so that it starts up in the background, without its screen taking over the display?
Alternatively, I'd be willing to launch the app, force it into the background, and redisplay the window of the previous app (whatever it might have been) that was running in the foreground. I don't know how to programmatically put the current app in the background and then determine the previous app and bring it back to the foreground.
I'm willing to do this any way possible: via Java, via one or more command-line utilities, via a Tasker plugin, via an Xposed module, or whatever.
Thank you in advance for any pointers to docs or any suggestions.
I discovered that the #0 entry of "dumpsys activity recents" gives the currently displayed activity ... at least on my rooted Marshmallow device. This gives me what I need.
My Android application is being restarted when using the launcher to launch it after I have used the app store to launch it (and visa versa). Is there any way to prevent this?
By restarted I mean that the activity stack is lost. This is important as our users are setting up and returning to an activity in the app intermittently over the course of an hour or so. After first install, they will likely have installed and opened the app from the app store, set themselves up and then backgrounded the app. Later they are likely to open the app from the launcher and lose all their state!
The problem is further compounded as we start a foreground service along with the set-up activity. Clicking the services notification should bring the user back to the set-up activity but, as with the launcher, if the user originally opened the app from the Play store, they again lose all their state!
Reproducing the problem
I've made a sample application here:
https://github.com/samskiter/LaunchTest
Note: it uses the BBC weather application package Id in order to allow you to quickly open from the app store (the "Open" button will be shown on the BBC weather application if this app is installed).
Steps are as follows:
Uninstall the BBC weather app if you have it
Install the LaunchTest app
Close the LaunchTest app from recents
Open the LaunchTest app from the BBC weather app page on the Play Store
Click the button to navigate to the Second activity
Background the application (press home)
Open the LaunchTest application from the app launcher
The state is lost! you are back at the First (root) activity
What I've tried
Using singleTask launch mode hasn't helped - it causes the app to be relaunched even if you use the launcher every time.
I've tried alwaysRetainTaskState - I don't really expect this to work as this only really affects things over about a 30 minute wait.
What I think is going on
There is no mechanism in the activity manager / intent system to open a running app in it's current state. Instead, I think the UID of the launching application is taken into account. If it is different then the Intent.FLAG_ACTIVITY_NEW_TASK flag is forced and so created a new task and dropping all my users' lovely state.
Inspecting Google Maps
Google maps has a very similar interaction model to our application: a setup UI, followed by an ongoing process the user is going through for a long period of time (navigation) with a paired, foreground service (the navigation service you can see in your notification bar). BUT GMaps doesn't suffer from this problem. I think this is because it uses only a single activity for all of it's interface and uses singleTask. So now, when you tap on the launcher after originally launching from the play store, the task can be reused.
In my opinion this exposes a hole in the android intent/activity management system. The whole point of the savedInstanceState/activity lifecycle is to prevent dropping state, but here we have a way to dump everything. My current best solution is to detect app restarts by the fact the service is running and try to get the user back to where they were, which is more than a little tricky.
If someone knows a way I can prevent my state being dropped on the floor when reopening from the app launcher after opening from the store, I would really appreciate it.
This is more like a workaround to your problem, but it seems that there may be no real solution.
My first thought was - since the whole setup will take a while anyway - why don't you just save some kind of bookmark ('firstLaunch') to Preferences, post a (delayed?) notification and finish the app, so that the user has to open it again by tapping on the launcher icon. Only then you start the real setup, so you will not lose information due to the installer vs launcher problem.
But the problem seems to have been around for some time and the following SO-posts may help:
Re-launch of Activity on Home button, but…only the first time
After tap on app icon,launcher create a new instance of root activity again & again
Hope this helps!
I'm facing the following problem. I want to make an android device to run only my application. All other apps and phone feautes should not be available to a user.
The reason why I want to achieve this is simple: I want to destribute devices with preinstalled application to my client but I don't want to let them use all phone featues.
This could work this way: just after android boots my application is launched automatically and than somehow all other staff is blocked.
Do you have any suggestions how to achieve that? Is it possible? Do I need to root a device?
I hope you get my problem. Any advice you can give will be greatly appreciated.
This is a bit crude way. But see if it is of any help.
If you create your application as a launcher it will start on boot(using system broadcast BOOT_COMPLETED).
Then you need to override all the three android buttons Home, back and recent apps.
To override back button you just have to override the onBackPressed() method.
For home button you will start a service which will run in background. This service will check if your app is in foreground or not. if not then it will bring it in foreground. so when the user presses home the service will sense the foreground app isnt yours and launch it.
But for this switching back of your app android takes approx 3 to 5sec. In that period of time you can display a warning text which will block the user from stopping the service from settings.Also if you remove the activity animations then it will appear seamless.
For recent apps button the above trick will do. If the user tries to close the app using this button your background service will sense it and launch your app.
so its the background service that does all the trick. if you some how stop the service or uninstall the app you are through :p