Android get previous activity
Intent intent = new Intent(this, next.class);
        intent.putExtra("activity","first");
        startActivity(intent);

Intent intent = getIntent();
        String activity = intent.getStringExtra("activity");

Intent i = new Intent(this, deliveries.class);
        i.putExtra("ActivityName", "ActivityOne");
        startActivity(i);

Bundle extra = getIntent().getExtras();
    String activityName= Long.parseLong(extra.getSerializable("ActivityName")
toString());

public ComponentName getCallingActivity()

Intent i = new Intent(Activity1.this, MainActivity.class).putExtra("from", "activity1");
startActivity(i);

if(getIntent().getStringExtra("from").equals("activity1")){
//From Activity 1
}else {
// Activity 2
}

startChildActivity("first", new Intent(this, First.class));

getParent()