Passing Information Between Activities

Hey everyone,

Here’s a little short blurb on how to pass information between Activities (I know this is probably documented, but at least for me it always helpful to see small examples in action):

public class A extends Activity {

@Override

public void onCreate(Bundle savedInstanceState) {

// code here

Intent i = new Intent( this, B.class );

i.putExtra( "int", 5);

i.putExtra( "string", "hello" );

startActivity( i );

}

}

And here’s the code for Class B:

public class B extends Activity {

@Override

public void onCreate(Bundle savedInstanceState) {

// code here

Intent i = getIntent();

int number = i.getIntExtra("int", -1);

String str = i.getStringExtra("string");
// number = 5
// str = "hello"

}

}

So basically the idea is you pass the intent to Class B and the intent acts like a standard Map object. For getIntExtra, if the app can’t find the value with key “integer”, then -1 is returned as the default, and for getStringExtra, if the app can’t find the key then null is returned.

Happy Coding.

– jwei