How to detect if came back from child activity?

Question

How can I detect if an activity came to focus after pressing the back button from a child activity, and how can I execute some code at that time?

Answer 1

You can also override both the onBackPressed() method and the onOptionsItemSelected() method and put some logic there. For example I put this into my BaseActivity which all the other Activities extends from:

@Override
public void onBackPressed() {
    // your logic
    super.onBackPressed();
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    if (item.getItemId() == android.R.id.home) {
        // your logic
    }
    return super.onOptionsItemSelected(item);
}