content: package com.airbnb.android.react.navigation.example;
  
  import android.os.Bundle;
  import android.support.annotation.Nullable;
  
  import com.airbnb.android.react.navigation.ScreenCoordinatorLayout;
  import com.airbnb.android.react.navigation.ReactAwareActivity;
  import com.airbnb.android.react.navigation.ScreenCoordinator;
  import com.airbnb.android.react.navigation.ScreenCoordinatorComponent;
  
  public class MainActivity extends ReactAwareActivity implements ScreenCoordinatorComponent {
    private static final String TAG = MainActivity.class.getSimpleName();
  
    private ScreenCoordinator screenCoordinator;
  
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      ScreenCoordinatorLayout container = (ScreenCoordinatorLayout) findViewById(R.id.content);
      screenCoordinator = new ScreenCoordinator(this, container, savedInstanceState);
  
      if (savedInstanceState == null) {
        screenCoordinator.presentScreen(MainFragment.newInstance());
      }
    }
  
    @Override
    public ScreenCoordinator getScreenCoordinator() {
      return screenCoordinator;
    }
  
    @Override
    public void onBackPressed() {
      screenCoordinator.onBackPressed();
    }
  }
  