Make the “up” button behave like the “back” button on Android

Question

The Android app design I\'m working with calls for the \"Up\" button to behave the same way the \"Back\" button behaves, but I\'m not sure how to make that happen.

I

Answer 1

from all three of your activities add the following

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case android.R.id.home:
            onBackPressed();
            return true;
    }

    return(super.onOptionsItemSelected(item));
}

when you press the up button on your app it will invoke onOptionsItemSelected with the id of android.R.id.home just catch that case and manually call onBackPressed()

Answer 2

KOTLIN

For anyone coming here in the age of Kotlin, if you set your toolbar up with the NavController, the "Up" button will behave like the back button.

toolbar.setupWithNavController(findNavController(R.id.nav_host_fragment),findViewById(R.id.full_drawer_layout))