React Native function callback

index.android.js ou index.io.js

 
...
  render() {
    return (
      <Navigator
        initialRoute={{component: Tela1}}

        configureScene={() => {
          return Navigator.SceneConfigs.FloatFromRight;
        }}
        renderScene={(route, navigator) => {
          _navigator = navigator;
          if(route.component){
            // Não esqueça de passar o navigator e o route
            return React.createElement(route.component, {navigator,route});
          }
      }} />
    );
  }
...

Tela1.js

 
...
   goToTela2 = () => {
      this.props.navigator.push({
        component: Tela2,
        callback: this.callback,
      });
    
  };

  callback = () => {
    console.log('callback');
  }
...

Tela2.js

 
...
   goBack(){
     this.props.route.callback();
     this.props.navigator.pop();
   }
...