Is it possible to detect when an app is executed (i.e., when the user clicks on the app's icon)? I attempted to register an intent of type Intent.ACTION_MAIN using a category of of type Intent.CATEGORY_LAUNCHER hoping this would let me know whenever an app is launched. The problem is, my broadcast receiver is never getting called.
Is this an illegal intent/category combination for which to register? Is there some method I can use to determine when an application launch occurs?
The application start Intent is not a broadcast, so there is no way to register a broadcast receiver and receive it. As previously answered here, there really is no way to detect the launch of the app. You could possibly write a service that polled the running tasks looking for the application's task (using the ActivityManager interface), but that's the best I can think of and it probably wouldn't be very performant.
There aren't any broadcast intent when an application is launched for the general case. If the application you want to detect is yours, you can fire your own intent broadcast, but if not, then no, you can't detect it.
Related
I am developing an app and this app needs to give a clear indication to the user when some event happens.
Only thing I could do until now is giving a notification in the notification area. But, I need to give a more visible notification, similar to the behavior when phone is ringing in an incoming call.
As I can understand, the reason why android is only allowing apps to give a notification is to prevent apps from disturbing the user. But, this app I am developing plays a vital role in the job of the user, so I don't think it is inappropriate to give a such strong notification.
I know it should be doable since apps like Viber can start an activity similar to a incoming phone call, even when the device is sleeping.
Does anyone know how to get this done?
Register a broadcast receiver, and add a custom action to it say CustomAction.Instead of showing notification, throw a broadcast and add CustomAction via intent filter.
Now in the onReceive method of broadcast listener, check
if(intent.getAction.equals("CustomAction"))Intent i = new Intent(context, YourActivity);
context.startActivity(i);
Sorry for not a formatted answer, I'm driving, will update it later for more clarification.
Update
Register broadcast receiver in a sticky service. So that service can be started automatically if killed and register broadcast register again.
Don't forget to unregister broadcast receiver in onDestroy() method of service and also in YourActivity when you purpose is resolved.
Just adding a sticky service (which does nothing) fixed the issue. Adding the service prevented the process getting killed when user exits the app and removes it from recent app list.
Because of the service, the app process is running even when a no UI is visible. In this state, if an activity is shown from the GCM service, it gets shown.
You can trigger a broascast as Vinay mentioned. If it still does not work, try using wake-locks. These wake-locks help in waking the device when it is in sleep mode. It will act like force wake and after calling wake-locks, you can perform your actions.
Hope it helped..
Thanks.
I'm new to android and trying to build a simple app which needs to listen for incoming sms. I know that I need to use the BroadcastReceiver class and I also know how to make my own broadcast receiver. But how do I start it? Does it start automatically if I set the code for it in the manifest? The app just has the Main activity, do I need to somehow add a broadcast receiver in the onCreate of this activity? I searched for an answer, but it's still not clear to me. I know it's not nice to ask, but it would be great if you can share some sample code. Thanks!
If you declare the receiver within your AndroidManifest.xml, then you shouldn't need to do anything more. When a broadcast gets sent, the Android system will look through all installed apps and notify each app that has declared the appropriate Receiver in its manifest, starting the app in the process if necessary. For most cases, such as SMS, that is how you want to declare receivers, because most broadcasts are sent with the intent that you want to open your app when its not currently running to react to the broadcast.
Alternatively, you may declare the broadcast within a running activity, which may be useful if you want the broadcast to directly update the UI in your running app.
BroadcastReceiver Documentation
I want to be able to detect when an application is opened and notify the user of something at the moment related to that same application but I don't know how to do this.
The user opens my app
I intent the service (background / foreground) and it successfully starts
Whenever the user opens another application I want to "catch it" and present a notification to the user
How can this be made? Are there any event listeners i need to use? Thank you very much.
If you are trying to catch "open app" intents in general, then it depends on how the app defined the intent. If it specified a class (explicit intent) then it will generally not be visible to your app unless the device is rooted, for example.
Implicit intents are broadcast and you simply need to define an intent filter in order to receive them. These are intents that allow Android and/or the user to select the appropriate app target based on data sent with the intent.
There are both useful and malicious motivations to do the kind of thing you are asking about. Read this:
Android Intent Security
And also the posted comment on learning about intents overall.
This is really simple. Here I am trying to figure out the solution. When your app goes on onPause() state then broadcast a message using BroadcastReceiver. On the other hand in another app just register for that broadcast.
I'm attempting to write a BroadcastReceiver to be notified when the Android OS kills an app in order to reclaim resources. I've tried filtering on "android.intent.action.PACKAGE_RESTARTED" but I never seem to receive that broadcast, even when I force close an application.
So, am I using the correct intent action filter? If not, what is the proper one? Or is this simply not possible?
Thanks!
Steve,
Unfortunately, if there is such an Action, it is not documented. The closest that you could get to is to run a service in the "foreground" and check if a particular application is running. There is no reason, after all, that you couldn't create such an Intent.
FuzzicalLogic
I have a program that has a broadcast receiver that listens for Phone_State and then sends a user defined intent.
Well, my problem is that the system also sends out an intent (the one that I am trying to replace with my program) .
So I am trying to find a way to CANCEL the systems intent.
I have found that if i have a timer just wait for a little bit, then I can send mine after the systems, but that is not very good, and sometimes defeats the purpose of my program.
Also, i cannot set my program as a default because it is not a full dialer program. Just one action of it.
Someone please help me find how to listen for and cancel a system intent/activity....
Someone please help me find how to
listen for and cancel a system
intent/activity
You cannot "cancel" an activity, period.
You cannot replace the dialer.
If the system Intent was sent via sendOrderedBroadcast(), then you can call abortBroadcast() from your BroadcastReceiver, and any lower-priority receivers will not get the broadcast. However, I have no evidence that ACTION_PHONE_STATE_CHANGED is an ordered broadcast, and I sincerely hope it isn't.
Whatever you are trying to do probably should be accomplished via modifications to your own custom firmware.