MainActivity.java

public class MainActivity extends AppCompatActivity
{
    private static final long MOVE_DEFAULT_TIME = 1000;
    private static final long FADE_DEFAULT_TIME = 300;

    private FragmentManager mFragmentManager;

    private Handler mDelayedTransactionHandler = new Handler();
    private Runnable mRunnable = this::performTransition;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        ButterKnife.bind(this);
        mFragmentManager = getSupportFragmentManager();

        loadInitialFragment();
        mDelayedTransactionHandler.postDelayed(mRunnable, 1000);
    }

    private void loadInitialFragment()
    {
        Fragment initialFragment = Fragment1.newInstance();
        FragmentTransaction fragmentTransaction = mFragmentManager.beginTransaction();
        fragmentTransaction.replace(R.id.fragment_container, initialFragment);
        fragmentTransaction.commit();
    }

    private void performTransition()
    {
        // more on this later
    }

    @Override
    protected void onDestroy()
    {
        super.onDestroy();
        mDelayedTransactionHandler.removeCallbacks(mRunnable);
    }
}