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Navigator.NavigationBar - cannot set property '_key' of undefined

See original GitHub issue

“react-native”: “0.32.0”,

tested with the example code still getting this error ?

test code

class App extends Component {
  render() {
    const routes = [
      {title: 'First Scene', index: 0},
      {title: 'Second Scene', index: 1},
    ];
    return (
      <Navigator
        initialRoute={routes[0]}
        initialRouteStack={routes}
        renderScene={(route, navigator) =>
          <TouchableHighlight onPress={() => {
            if (route.index === 0) {
              navigator.push(routes[1]);
            } else {
              navigator.pop();
            }
          }}>
          <Text>Hello {route.title}!</Text>
          </TouchableHighlight>
        }
        style={{padding: 100}}
        navigationBar={
           <Navigator.NavigationBar
             routeMapper={{
               LeftButton: (route, navigator, index, navState) =>
                { return (<Text>Cancel</Text>); },
               RightButton: (route, navigator, index, navState) =>
                 { return (<Text>Done</Text>); },
               Title: (route, navigator, index, navState) =>
                 { return (<Text>Awesome Nav Bar</Text>); },
             }}
             style={{backgroundColor: 'gray'}}
           />
        }
      />
    );
  }
}

Issue Analytics

State:
Created 7 years ago
Reactions:4
Comments:9 (1 by maintainers)

Top GitHub Comments

2reactions

samuelkraftcommented, Aug 29, 2016

I have a similar error. undefined is not and object (evaluating '_this._key = guid()') in NavigatorNavigationsBar.js:114 after upgrading to 0.32.

Building with Xcode 8 for iOS 10 - not sure if related.

1reaction

ardavankcommented, Oct 22, 2016

I still have the same issue using RN 0.35.0

 <Navigator
                style = { styles.container }
                navigationBar={
                    <Navigator.NavigationBar
                        routeMapper={{
                            LeftButton: (route, navigator, index, navState) =>
                            { return (<Text>Cancel</Text>); },
                            RightButton: (route, navigator, index, navState) =>
                            { return (<Text>Done</Text>); },
                            Title: (route, navigator, index, navState) =>
                            { return (<Text>Awesome Nav Bar</Text>); },
                        }}
                        style={{backgroundColor: 'gray'}}
                    />
                }
                initialRoute = { { name: ROUTES.TODOS } }
                renderScene = { this.renderScene.bind(this) }
                configureScene = { () => { return Navigator.SceneConfigs.FloatFromRight; } } />