Introduction
It's the simplest thing. An Android developer will need some time passing a value from one intent to another, making intents aware of each other.
Using the Code
Intent myIntent = new Intent(this, mySecondActivity.class);
myIntent.putExtra("KeyName", keyValue);
startActivity(myIntent);
Points of Interest
You can pass whatever value you want to the other activity. Using the below code, you can retrieve the values given from the previous activity.
Bundle extras = getIntent().getExtras();
if (extras != null) {
String value = extras.getString("KeyName");
}