Android facebook sdk does not call callback after login

Having the attribute android:noHistory="true" set for your callback activity in the AndroidManifest.xml file will also result with the callback methods not firing.

maybe you forget to handle the results after login...

check the override method onActivityResult..

because it handle the results back to the MainActivity,

maybe this can help your problem..

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    Session.getActiveSession().onActivityResult(this, requestCode,
            resultCode, data);
}

Update 1

For newer SDK use:

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    callbackManager.onActivityResult(requestCode,
            resultCode, data);
}