How can I pass values between Activities on Android?

Question

This is the navigation of my application:

Activity1 calls Activity2 → Activity2.finish(), call Activ

Answer 1

Umesh shows a good technique but I think you want the opposite direction.

Step 1

When starting Activity 2 and 3, use startActivityForResult. This allows you handle the result in the calling activity.

startActivityForResult(MY_REQUEST_ID);

Step 2

In Activities 2 and 3, call setResult(int, Intent) to return a value:

Intent resultData = new Intent();
resultData.putExtra("valueName", "valueData");
setResult(Activity.RESULT_OK, resultData);
finish();

Step 3

In your calling activty, implement onActivityResult and get the data:

protected void onActivityResult(int requestCode, int resultCode,
          Intent data) {
      if (requestCode == MY_REQUEST_ID) {
          if (resultCode == RESULT_OK) {
            String myValue = data.getStringExtra("valueName"); 
            // use 'myValue' return value here
          }
      }
}

Edit:

Technique #2

Yes, you can also use global application state by adding a class to your application that extends Application, see this StackOverflow answer

Answer 2

Use the session id to the signout activity in the intent you're using to start the activity:

Intent intent = new Intent(getBaseContext(), SignoutActivity.class);
intent.putExtra("EXTRA_SESSION_ID", sessionId);
startActivity(intent)

See this tutorial.

Answer 3

Why even bother following that kind of structure... if three returns to one? Just send an intent with your data from three to one and handle it accordingly.

Answer 4

Sending an Intent from activity 3 to 1 would require some trigger like a button or perhaps the onStop lifecycle method to send it. Better to have the result be automatically send with the setResult method.

Answer 5

Also there is other technique, you can call startActivity(new Intent(getApplicationContext(),Activity1.class)) method along with the Bundle class to transfer data from activity3 to activity1.

Answer 6

On Android it is possible to launch another app of a specified package name, passing an argument to it.

public static void launchApp(Context context, String packageName) {
    Intent intent = context.getPackageManager().getLaunchIntentForPackage(packageName);

    if(intent == null) {
        intent = new Intent(Intent.ACTION_VIEW, Uri.parse("market://details?id=" + packageName));
    }
    intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
    intent.putExtra(Intent.EXTRA_TEXT, "*argument to send*");
    context.startActivity(intent);
}

The code below can be used to retrieve the argument in the target app.

public static String getArgument(Activity activity) {
    return activity.getIntent().getStringExtra(Intent.EXTRA_TEXT);
}

Only a reference to Activity is needed, this is useful in Unity where it is messy to subclass Activity.