My application has two activities A and B. A is the root of the task, and is the one that is launched from the launch icon. B can be started from A.
As well as starting A from the launch icon, it is possible to launch A by clicking on a file in another application, e.g. clicking on an email attachment or a file in Drive. I have done this by adding actions and categories to the intent filter in the manifest file.
I want to make it so that when A is launched from another application, instead of creating a new task I want the existing task to resume in the same state it was in before. This could be activity A or B, wherever the user happened to be before they pressed home.
I have tried all kinds of launch modes and intent flags but nothing seems to work.
Broadcast an intent that's identical to the launcher intent in your manifest:
Intent intent = new Intent(context, MainActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.setAction(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_LAUNCHER);
I don't know why, but this raises the existing task instead of starting a new one. By contrast, a launcher intent obtained the "official" way will actually start a new task:
Intent intent = context.getPackageManager()
.getLaunchIntentForPackage(context.getPackageName());
change launchmode to singletask. and listening onNewIntent()
Related
When user press "Home Button" my app go to Background, but is still running. I need bring my app to front again. For example i've this code:
Context ctx=getApplicationContext();
Intent i =ctx.getPackageManager().getLaunchIntentForPackage("com.example.test");
ctx.startActivity(i);
but this code is to open app in different activity, there are a method or something to do this "correctly"?
You can simulate the "launching" of the app the same way that Android launches the app when the user selects it from the list of available apps. If the user starts an application that is already running, Android just brings the existing task to the foreground (which is what you want). Do it like this:
Intent intent = new Intent(context, SplashScreen.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); // You need this if starting
// the activity from a service
intent.setAction(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_LAUNCHER);
startActivity(intent);
(Source: https://stackoverflow.com/a/12075313/3529926)
You can set this flag to your intent
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_SINGLE_TOP);
and set the launch mode of your activity to single task in manifest (add this is your activity tags):
android:launchMode="singleTask"
I have a service that once it completes a task it launches an intent to start an activity from my application. Like this:
Intent i = new Intent(MyService.this, MyActivityToBringToFront.class);
i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
//i.addFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
//i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
//i.addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
startActivity(i);
This service can be running even after my application has been closed. When this is the case and my application is closed I need it to bring the activity to the front of whatever the user is currently doing. So if the user is in a different app I need my activity to pop up in front. Is this possible. None of the flags had any effect. Basically I need it to be like the system phone application. When you get a phone call it always brings the phone to the front. How can I do this? Thanks!
First of all you need to keep context in memory to make intent's.
Secondary you need a mechanism that can re-obtaining your context every 24 hours because usually context stay alive in 24 hours.
After.
Launching Activity from service :
Intent dialogIntent = new Intent(getBaseContext(), myActivity.class);
dialogIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
getApplication().startActivity(dialogIntent);
source : https://stackoverflow.com/a/3607934/2956344
To push activity on top add
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_SINGLE_TOP);
Intent i = new Intent();
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
i.setAction("android.intent.action.VIEW");
i.setComponent(ComponentName.unflattenFromString("com.example.package/com.example.package.activityName"));
startActivity(i);
Intent i = new Intent(MyService.this, MyActivityToBringToFront.class);
i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK|Intent.FLAG_ACTIVITY_CLEAR_TOP);
context.startActivity( i);
And API reference is
If set, and the activity being launched is already running in the
current task, then instead of launching a new instance of that
activity, all of the other activities on top of it will be closed and
this Intent will be delivered to the (now on top) old activity as a
new Intent.
For example, consider a task consisting of the activities: A, B, C, D.
If D calls startActivity() with an Intent that resolves to the
component of activity B, then C and D will be finished and B receive
the given Intent, resulting in the stack now being: A, B.
The currently running instance of activity B in the above example will
either receive the new intent you are starting here in its
onNewIntent() method, or be itself finished and restarted with the new
intent. If it has declared its launch mode to be "multiple" (the
default) and you have not set FLAG_ACTIVITY_SINGLE_TOP in the same
intent, then it will be finished and re-created; for all other launch
modes or if FLAG_ACTIVITY_SINGLE_TOP is set then this Intent will be
delivered to the current instance's onNewIntent().
This launch mode can also be used to good effect in conjunction with
FLAG_ACTIVITY_NEW_TASK: if used to start the root activity of a task,
it will bring any currently running instance of that task to the
foreground, and then clear it to its root state. This is especially
useful, for example, when launching an activity from the notification
manager.
launching an activity from a service isn't always a good idea. You may want to use notification for that. If the user clicks on the notification, thats the time you show the Activity.
My application has two activities A and B. A is the root activity and set with singleTop launchMode. B is started from A, i.e. the task stack is (A->B)
I add a status notification to launch the application as long press Home button. The notification intent point to activity A.
When the task stack is (A) only, the intent invokes onNewIntent() from existing A, as expected.
When the task stack is (A->B), the intent create new activity A. But what I wants is resume task (A->B) as switch recent apps by long press Home button.
Is the problem caused by incorrect launch mode used? or any flags need to be added to the notification intent?
Thanks.
You can use the following from your notification manager:
Intent intent = new Intent(context, ActivityA.class);
intent.setAction(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_LAUNCHER);
context.startActivity(intent);
Make sure that your ActivityA is not launched with FLAG_ACTIVITY_NEW_TASK.
On my code I have 2 apps.
the app a that starts app b, like a launcher.
the code app a looks like that:
Intent i = new Intent(Intent.ACTION_MAIN);
PackageManager manager = getPackageManager();
i = manager.getLaunchIntentForPackage("com.test.vayo");
i.addCategory(Intent.CATEGORY_LAUNCHER);
startActivity(i);
finish();
the code on app B:
Intent intent = new Intent(this.context, first.class);
intent.setFlags(intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
context.startActivity(intent);
finish();
my problem that to start task b only if a didnt start the app b.For that I am trying to bring to front the task that already running and not to start all activities from the root one, just to bring to front back stack of the privous task.
for that I am using FLAG_ACTIVITY_REORDER_TO_FRONT its works only if I run first app b and the app a, but if I run a and then run b it isnt working,its starts b from the root activity.
In your manifest file, for launcher activity of B, declare
android:launchMode="singleTask"
You do not need to do anything in B.
I did it with flags one flag on the app a and the other one on the app b, the flag
intent.setFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
Is it possible to create two entry points to an application in Android, I mean can I switch the main activity programmatically?
Every exported activity is a potential entry point into your app; a foreign app can start any of them with an intent. (An intent-filter comes with an implicit android:export.) You can however only have one entry point that the launcher will respect. To simulate a second launch-point, either
Provide a completely separate app with the purpose of starting one of your exported activities, or
Give your 'launch' activity the sole purpose of immediately starting one or another activity based on some logic (a saved preference, a phase-of-moon calculation, anything).
check this one below
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_LAUNCHER);
intent.setComponent(new ComponentName(packageName,mainActivity));
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
ctx.startActivity(intent);
I think you are talking about launching activity decision based on some events, then you need to add a broadcast receiver, like by clicking on app icon on launcher if you want to start Activity1. then add intent filters to this activity Action_MAIN and ACTION_LAUNCHER, if you want to start Activity2 on phone boot up, then add filter to this activity, BOOT_COMPLETED.
If you are talking about to launch other apps from your apps then this can be the code:
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_LAUNCHER);
intent.setComponent(new ComponentName(packageName,mainActivity));
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
ctx.startActivity(intent);