How to implement the Android ActionBar back button?

Question

I have an activity with a listview. When the user click the item, the item \"viewer\" opens:

List1.setOnItemClickListener(new OnItemClickListener() {
    @Ov         


        

Answer 1

Building on Jared's answer, I had to enable and implement the action bar back button behavior in several activities and created this helper class to reduce code duplication.

public final class ActionBarHelper {
    public static void enableBackButton(AppCompatActivity context) {
        if(context == null) return;

        ActionBar actionBar = context.getSupportActionBar();
        if (actionBar == null) return;

        actionBar.setDisplayHomeAsUpEnabled(true);
    }
}

Usage in an activity:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    ...

    ActionBarHelper.enableBackButton(this);
}