How to send my application to Background use code?
How to catch event when "Home key" is pressed?
Many thanks !
Intent i = new Intent();
i.setAction(Intent.ACTION_MAIN);
i.addCategory(Intent.CATEGORY_HOME);
this.startActivity(i);
Home key press event cannot be captured as an android security feature.
You can send your activity into the background using moveTaskToBack.
There's no way to catch a HOME key press, or even to detect that it was pressed. The closest you can come is to write a replacement Home screen that uses android.intent.category.HOME. I believe that the user would have control over which activity should get to handle such an intent.
You can't catch the home key... it would defeat it's purpose after all.
If you simply want to know when your Activity is no longer visible, override the onPause() and/or onStop() methods.
If you want to start doing something in the background at this point, you could create a Service. A Service will run in the background, unlike an Activity which is more likely to be killed.
If you want to send some data to this Service from your Activity, you can use Intents and Extras. If you want to send more than the simple types of data you can send with extras, use the Application class. (Described in more detail here)
Related
I am trying to resume another another android application from the background programmatically. Is it possible ? How can I do it ?
just launch another app.
Intent intent = getActivity().getPackageManager().getLaunchIntentForPackage(another app packagename)
start this intent.
(you can also use intent by URI .And make sure suitable lauchmode)
If you mean something like: when user presses home or back button your application launches another application, then you can use onStop() or onPause() methods.
I have an Activity and assume that has been launched. When the other application use startActivity method to start my Activity, my Activity will show and run the onResume Method, but I can't find any way to get the intent which is used in startActivity method by the other application. I want to get the extra data in the intent. How can I do?
EDIT
My Activity is singleTask, and I want to get the startActivity intents form other applications. I think it is not associate with filters.
Have you tried using getIntent() ?
Then you can do:
this.getIntent().getExtras();
After that if you need new intents just override the onNewIntent function in your activity.
I simply say an example. When we need to share something. We click share button which shows a list of app by which we can share our things.
So, if you want to make that kind of app which can receive other app data then you need make your activity capable of receiving that data. In order to receive implicit intents, you must include the CATEGORY_DEFAULT category in the intent filter in manifest.
Below this link you will get some more information : http://developer.android.com/training/basics/intents/filters.html
I am looking for a way to launch another app from within my app but so that the focus is not changed from my app to the app launched.
I.e currently I have the new app launched via a intent, however when this is carried out the new app is launched and becomes the app in view, I need it to be kept in the background with my app still in view.
The reason for this?
I am developing an application for internal use that will act like a lock-screen to the device so although things must happen in the background the 'lock-screen' must always be on top.
I have done some research into intents and launching other apps but can not find anything about what I need.
Hope you can help thank you!
Currently the terminal is called like this:
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.setComponent(new ComponentName("jackpal.androidterm", "jackpal.androidterm.RemoteInterface"));
intent.setAction("jackpal.androidterm.RUN_SCRIPT");
intent.putExtra("jackpal.androidterm.iInitialCommand", cmdString);
The reason it needs to be running in the background is so that the app can run commands in terminal without the user having access, but then they 'unlock' the screen they need to then be able to view the terminal and what commands are being run etc
You can not startActivity in Background.Instead start the activity and minimise the activity(in your case this activity is of different application) using moveTaskToBack(true);
In your case, put a condition based on your intent and its params and use moveTaskToBack(true); so that activity will be minimised only when your application launches.
This won't be possible, you will have to start a background Service that does the actual work and only launch the Activity you want to navigate to once your foreground Activity is finished. Depending on your architecture, you can store the Activity to call when your foreground Activity is finished and change it from the service. That way you will have your desire behaviour without having to actually call the Activity.
In addition to the answer from #Meher, in the intent for your current starting activity, you can add the flag FLAG_FROM_BACKGROUND.
With this you get rid of the "blinking" effect (the one where your activity shows for one fraction of second while it discovers wether to go to background)
How to close an android app if more than one activity is in active state?
A blog post entitled Exiting Android Application will show how to exit an Android app:
When the user wishes to exit all open activities, they should press a button which loads the first Activity that runs when your app starts, in my case "LoginActivity".
Intent intent = new Intent(getApplicationContext(), LoginActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
intent.putExtra("EXIT", true);
startActivity(intent);
The above code clears all the activities except for LoginActivity. LoginActivity is the first activity that is brought up when the user runs the program. Then put this code inside the LoginActivity's onCreate, to signal when it should self destruct when the 'Exit' message is passed.
if (getIntent().getBooleanExtra("EXIT", false)) {
finish();
}
I got an easy solution for this problem
From the activity you press the exit button go to the first activity using the following source code. Please read the documentation for FLAG_ACTIVITY_CLEAR_TOP also.
Intent intent = new Intent(ExitConfirmationActivity.this, FirstActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);
Now overide onResume() of the first activity using finish()
The answer is simple: You really do not need to 'close' an Android application. If no activity is shown any more, the system will kill the process after some time. The users can close activities by pressing the 'back' button. Reto Meier explains it pretty well here:
http://blog.radioactiveyak.com/2010/05/when-to-include-exit-button-in-android.html
You might also want to read this thread; it is very helpful to say the least: Quitting an Android application - Is it frowned upon?
Well, you shouldn't close your applications, as the system manages that. Refer to the posts/topics in the other answers for more information.
However, if you really, really want to, you can still call System.exit (0); like in any other Java application.
EDIT
ActivityManager actmgr = (ActivityManager) this.getSystemService (Context.ACTIVITY_SERVICE);
actmgr.restartPackage ("com.android.your.package.name");
I remembered something. I was trying to use this code to restart my application, but it only managed to kill my app. You can try it and see if it works for you.
I asked a similar question a couple of weeks back. Do go through the answers and comments for more perspective and possible solutions.
IMO quitting an application depends on what your application does and the user expectations. While I understand the rationale on not having a quit button I also do believe that it's a choice that the application designer has to make based on the situation.
Once your last Activity looses focus, Android will unload your process according to the current system needs / free resources.
You shouldn't really care about that - just use the lifecycle onStart, OnStop etc... to manage your state.
If you want to exit from one Android activity, this will bring you back to the previous activity or another activity from a specific place in current activity.
finish();
System.exit(0);
i have a button to close my app with this code:
finish();
the problem is that this button doesn't exit of my app... it simply closes the current intent ant returns to the previous intent (window) of my app....
how i can do a real exit/close button?
i tryed with this:
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_HOME);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
but it doesn't works, because when i turn back into my app, the app comes in the last opened window, and not in the first window of the app, how i can do that? i need that when i re-open my app it starts on the first window of my app
If you really want your app to die. You could initiate each intent with startActivityForResult(). then before each finish() set the result to send back. in each parent activity you can override onActivityResult() to test whether the result received means the application needs to end. if so you can call another set result and finish(). repeat this in all activities and you will find that your application terminates entirely.
Incidentally I'm writing this from memory. function names may not be exact.
Hope that helps.
p.s. re-read your requirements. you can always stop the finish loop at your first activity.
I would do it this way:
I would define my initial activity (i.e. MainMenu) with a Launch Mode of singleTop
I would then invoke my MainMenu from the activity that is going to close the application.
startActivity(new Intent(this, MainMenu.class).addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP).putExtra("closeProgram", true);
Then override the onNewIntent in the MainMenu activity; check for the extra boolean of "closeProgram", if the value is true, then do a finish();
Haven't tried it but I think it should work.
I recommend you read this: http://blog.radioactiveyak.com/2010/05/when-to-include-exit-button-in-android.html
Chances are, you don't want an exit button. Perhaps a logout button, but that's it.
finish() closes activity (this is what you call intent, but it's not correct), not application. Application can not be finished at all (only forcefully killed like task killers do). You should design your activity stack in such a way that it will suit your needs. May be you should look at stack rearrangement examples in ApiDemos.
you can try this: System.exit(0);