Display Back Arrow on Toolbar

If you are using an ActionBarActivity then you can tell Android to use the Toolbar as the ActionBar like so:

Toolbar toolbar = (Toolbar) findViewById(R.id.my_awesome_toolbar);setSupportActionBar(toolbar);

And then calls to

getSupportActionBar().setDisplayHomeAsUpEnabled(true);getSupportActionBar().setDisplayShowHomeEnabled(true);

will work. You can also use that in Fragments that are attached to ActionBarActivities you can use it like this:

((ActionBarActivity) getActivity()).getSupportActionBar().setDisplayHomeAsUpEnabled(true);((ActionBarActivity) getActivity()).getSupportActionBar().setDisplayShowHomeEnabled(true);

If you are not using ActionBarActivities or if you want to get the back arrow on a Toolbar that's not set as your SupportActionBar then you can use the following:

mActionBar.setNavigationIcon(getResources().getDrawable(R.drawable.ic_action_back));mActionBar.setNavigationOnClickListener(new View.OnClickListener() {   @Override   public void onClick(View v) {       //What to do on back clicked   }});

If you are using android.support.v7.widget.Toolbar, then you should add the following code to your AppCompatActivity:

@Overridepublic boolean onSupportNavigateUp() {    onBackPressed();    return true;}

I see a lot of answers but here is mine which is not mentioned before. It works from API 8+.

public class DetailActivity extends AppCompatActivity@Overrideprotected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_detail);    // toolbar    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);    setSupportActionBar(toolbar);    // add back arrow to toolbar    if (getSupportActionBar() != null){        getSupportActionBar().setDisplayHomeAsUpEnabled(true);        getSupportActionBar().setDisplayShowHomeEnabled(true);    }}@Overridepublic boolean onOptionsItemSelected(MenuItem item) {    // handle arrow click here    if (item.getItemId() == android.R.id.home) {        finish(); // close this activity and return to preview activity (if there is any)    }    return super.onOptionsItemSelected(item);}

There are many ways to achieve that, here is my favorite:

Layout:

<android.support.v7.widget.Toolbar    android:id="@+id/toolbar"    android:layout_width="match_parent"    android:layout_height="?attr/actionBarSize"    app:navigationIcon="?attr/homeAsUpIndicator" />

Activity:

Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);toolbar.setNavigationOnClickListener(new View.OnClickListener() {    @Override    public void onClick(View v) {        // back button pressed    }});