Using Intent Between Activities, In Reverse - Android

I am quite new to android programming (aswell as java in general) and have run into an issue that has me stumped. I am building a basic app (for practice) that accesses an already

Solution 1:

Source: Getting a Result from an Activity

From Activity1:

publicstaticfinalStringRESULT_REQUEST=1;

When you want to start Activity2:

Intent intent = newIntent(this, Activity2.class);
startActivityForResult(intent, RESULT_REQUEST);

This will be called when Activity2 is finished:

@OverrideprotectedvoidonActivityResult(int requestCode, int resultCode, Intent data) {
    // Check which request we're responding toif (requestCode == RESULT_REQUEST) {
    // Make sure the request was successfulif (resultCode == RESULT_OK) {
        Stringresult= data.getStringExtra("result");
    }
    }
}

And Activity2, when you are done and want to send the string back:

IntentreturnIntent=newIntent();
    returnIntent.putExtra("result","some string");
    setResult(RESULT_OK,returnIntent);
    finish();

We have used the RESULT_REQUEST to uniquely identify our own REQUEST, and you do need to check if the requestCode is the same with the one you have started the second activity.

Solution 2:

Put the value in the intent

Intent i = newIntent(SecondScreen.this, FirstScreen.class);   
i.putExtra("STRING_I_NEED", strName);

Then, to retrieve the value:

Bundleextras= getIntent().getExtras();
    if(extras == null) {
        newString= null;
    } else {
        newString= extras.getString("STRING_I_NEED");
    }