Activity for result | Android

To get data from our other activity (Say SecondActivity) that is opened by an activity(Say MainActivity), use startActivityForResult().  SecondActivity send back result via intent. While sending back intent it will set the response using setResult()

• RESULT_OK : Result send is OK.
• RESULT_CANCELED : Activity cancel to send result.

Finally in MainActivity class will get result in onActivityResult() method and check the request code and result code.

//****** File : MainActivity.java ******
// Start second activity. 2 is request code 
Intent intent = new Intent(MainActivity.this, SecondActivity.class); 
startActivityForResult(intent, 2);

// Call Back method to get the Message form other Activity
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {

  super.onActivityResult(requestCode, resultCode, data);
  
  // Check if the request code is same as what is passed  here it is IntentId
  if (requestCode == IntentId) {
    if (resultCode == RESULT_OK) {

      // Result code is OK
      String message = data.getStringExtra("message");
    }
    else if (resultCode == RESULT_CANCELED){
      // Handle failure case
    }
  }
}

//****** File : SecondActivity.java ******
Intent intent = new Intent();

// Put Message to pass over intent
intent.putExtra("message",message);

// Set result OK
setResult(RESULT_OK,intent);

// Set result CANCEL
setResult(RESULT_CANCELED, intent);

Example

Create a MainActivity, and launch another activity for the result.

public class MainActivity extends AppCompatActivity {

    public static final int ASK_REQUEST =1;
    private static Button getMessageBtn;

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        getMessageBtn = (Button)findViewById(R.id.secondActivityBtn);
        getMessageBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

            // Start SecondActivity with the request code
            Intent in = new Intent(MainActivity.this, SecondActivity.class);
            startActivityForResult(in, ASK_REQUEST);
            }
        });
    }

    // Call Back method to get the Message form other Activity
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        // Check if the request code is same as what is passed  here it is ASK_REQUEST
        if (requestCode == ASK_REQUEST) {

            if (resultCode == RESULT_OK) {
                // Result code is OK, get String extra and set message
                String message = data.getStringExtra("message");
            }
            else if (resultCode == RESULT_CANCELED){

            }
        }
    }
}

Second activity handles the intent, process request and send back the response to the calling activity.

public class SecondActivity  extends AppCompatActivity implements OnClickListener{

    private static Button cancel, submit;

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.second_activity);

        cancel = (Button)findViewById(R.id.cancel);
        submit = (Button)findViewById(R.id.submit);

        cancel.setOnClickListener(this);
        submit.setOnClickListener(this);
    }

    @Override
    public void onClick(View view) {
        switch (view.getId()){
            case R.id.submit: {
                    // Set the resultCode to Activity.RESULT_OK to indicate a success and attach the Intent
                    // which contains result data
                    Intent intent = new Intent();
                    intent.putExtra("message", "Hello World");
                    setResult(RESULT_OK, intent);

                    // Close the SecondActivity return to MainActivity
                    finish();
                break;
            }
            case R.id.cancel: {
                Intent intent = new Intent();
                setResult(RESULT_CANCELED, intent);
                finish();
                break;
            }
        }
    }
}