Develop Reference

Remove all activities of an app from every existing task in Activity Back Stack

Is there a way of removing all activities belonging to the app in foreground (my app)?
The activities might be present in different tasks. Also after removing all activities my app should return to home screen which is launcher activity of my app.
Any kind of help would be greatly appreciated.

You need to call your activity like this.
Intent login=new Intent(MainActivity.this,HomeActivity.class);
login.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
login.putExtra("flag",false);
startActivity(login);
finish();

You may need
Intent intent = new Intent(getApplicationContext(), MainActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK|Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
FLAG_ACTIVITY_CLEAR_TASK
Any existing task that would be associated with the current activity to be cleared before the desired activity is started. Simply old activities are finished.
FLAG_ACTIVITY_NEW_TASK
If set, this activity will become the start of a new task on this history stack.
for more details, Intent Flags

Intent i = new Intent(OldActivity.this, NewActivity.class);
// set the new task and clear flags
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(i);
finish();

Closing an android application programatically in android

I have a application that has two activities
Activity1
Activity2
Now i start Activity1 and move to Activity2 now i want to close the application at a moment
If i use finish() i am able to close only Activity2 and not
Activity1
What i want to do ::
i want my application to quit(close all activities and go to
homescreen)
But i don't want my apk to be removed from android system itself
How can i achieve this ?
{Edit}
I used the code(Activity2 has a fragment which launched a dialog on
"ok" condition in positive condition i am performing this condition below)
I am able to launch the previous activity but it is not canceled, its
just reloaded
Intent intent = new Intent(getActivity(), SplashActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
getActivity().finish();

You need to make your Activity2 as "top task" with a Flag when you call it as follows:
Intent intent = new Intent(Activity1.this, Activity2.class);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
See the Reference:
If set in an Intent passed to Context.startActivity(), this flag will cause any existing task that would be associated with the activity to be cleared before the activity is started. That is, the activity becomes the new root of an otherwise empty task, and any old activities are finished.
Then, call finish() in your Activity2. This should do the trick.

There is a way to kill your application process, but it is not recommended
this.finish();
Process.killProcess(Process.myPid());
This will kill your application and releases all the memory associated with it.
Note: Assuming your app has a single process id

Do like this
Intent intent = new Intent(Activity1.this, Activity2.class);
startActivity(intent);
Activity1.this.finish();

Intent intObj=new Intent(this, Homescree.class);
intObj.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP |
Intent.FLAG_ACTIVITY_CLEAR_TASK |
Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intObj);

Clearing all activities in android

I have 4 Activities 1.Home,2.B,3.C and 4.D. Whenever I start Home from Activity D I want to finish all other activities. I Used this code, but when I press back button from Home it brings me to the previous activity. What I did wrong here.?
Intent intent = new Intent(getApplicationContext(), Home.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent)

You can try this,
Intent intent = new Intent(getApplicationContext(), Home.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
Note: As described in FLAG_ACTIVITY_CLEAR_TOP documentation
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.

intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
This will work only for activities which are still in the activity stack. I believe you are finishing the Home Activity when going to B. So that CLEARTOP won't work.
Now try something like this.
You need to set an Extra with intent Of "D" to Home. Then you have to check the Intent extra in Home, call finish() if the extra matching
Intent intent = new Intent(contxt, Home.class);
intent.putExtra("urString",defaultvalue);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);
// Checking the intent extra at "HOME"
if(getIntent().hasExtra("urString")){
// manage your own way
finish();
}

In manifest.xml file set android:nohistroy="true" for all the activities

Finish Current Activity and start a new one

I have a Fragment F. After getting result from a service, F needs to finish the activity it is in and launch a page in the web browser which I do using an intent.
It does seem to work fine if the user presses the back button. However, if he launches the app from recent apps, the activity isn't finished.
I have thought about otherways of doing it. Like finishing the current activity and opening the page from the parent activity. But I'll have to make a lot of changes in the flow. So that would be my last option. Is there any way to make sure that the activity is finished even when I launch it from recent apps?
Intent intent = new Intent(Intent.ACTION_VIEW,Uri.parse(url));
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);
getActivity().finish();
Edit: Added code.

try this code for start browser and clear all the stacks of your application
Intent intent = new Intent(); // need to set your Intent View here
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
getActivity().startActivity(intent);
getActivity().finish();
Updated
Try this attribute in your activity in AndroidManifiest.xml file
<activity android:name=".MainActivity"
android:excludeFromRecents="true" ...

use the following code
Intent intent = new Intent(getApplicationContext(), Home.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);
this.finish();

Android- How to handle application's multiple instances

What the way to manage multiple instances of Android application? I want to close the ruuning application's instance when user launch the same application from Application menu.
Regards,
Android_IT

This is what I use to clear the backstack and start from the beginning if that is what you're looking for
Intent intent = new Intent(this, Main.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);