renderRightButton and renderLeftButton are not working

[atn4z7]

Version

• react-native-router-flux v3.2.6
• react-native v0.22

Expected behaviour

renderRightButton and renderLeftButton should be working for scenes that are not tabs

Actual behaviour

renderRightButton and renderLeftButton are only working for scenes that are tabs

Steps to reproduce

1. add renderRightButton={()=>} to loginModal scene in Example.js

  <Scene key="login" direction="vertical"  >
      <Scene key="loginModal" component={Login} title="Login" renderRightButton={()=><Right/>}/>
      <Scene key="loginModal2" hideNavBar={true} component={Login2} title="Login2" panHandlers={null} duration={1}/>
  </Scene>

1. run the example
2. right button is not rendered

[atn4z7]

turned out I just need to specify it at the parent scene like this

      <Scene key="login" direction="vertical"
                  renderLeftButton={ButtonRenderer.back}>
                  <Scene key="loginModal" component={Login} schema="modal" title="Login"
                    navigationBarStyle={styles.navBar}/>

[sneerin]

what's ButtonRenderer.back?