https://stackoverflow.com/a/37185334
I think onSupportNavigateUp() is best and Easiest way to do so
check the code below
if you want it programmatically Add this line in onCreate() method
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
Note: make sure Actionbar is not null.
And Override this method
@Override public boolean onSupportNavigateUp(){ finish(); return true; }
thats it
OR Non-programmatically you can add meta to the activity in manifest file as
<meta-data android:name="android.support.PARENT_ACTIVITY" android:value="MainActivity" />
Other solution:
mToolbar.setNavigationOnClickListener (new View.OnClickListener () { @Override public void onClick(View view) { onBackPressed(); } });