以下是 React Native 应用启动一段时间后，通过杀死 Meteor 服务器断开与 Meteor (DDP) 服务器的连接时的 Android 日志输出。

使用 console.log("<App /> render")指示何时 render App的功能组件被调用时，似乎每当 render在 createContainer 之后再次调用函数传递给它一些新的 props , Key is already defined触发错误。

是什么导致了这个错误/警告，我们该如何解决？该应用程序仍然运行良好，但这里肯定有问题。

12-23 02:27:01.875 31197 19338 I ReactNativeJS: Running application "RNapp" with appParams: {"initialProps":{},"rootTag"
:1}. __DEV__ === true, development-level warning are ON, performance optimizations are OFF
12-23 02:27:01.891 31197 19338 I ReactNativeJS: render
12-23 02:27:01.995 31197 19338 I ReactNativeJS: Connected to DDP server.
12-23 02:27:01.999 31197 19338 I ReactNativeJS: Connected to DDP server.
12-23 02:27:02.012 31197 19338 I ReactNativeJS: render
12-23 02:27:02.013 31197 19338 I ReactNativeJS: Key home is already defined!
12-23 02:27:02.013 31197 19338 I ReactNativeJS: Key welcome is already defined!
12-23 02:27:02.013 31197 19338 I ReactNativeJS: Key loading is already defined!
12-23 02:27:02.013 31197 19338 I ReactNativeJS: Key root is already defined!
12-23 02:27:34.592 31197 19338 I ReactNativeJS: Disconnected from DDP server.
12-23 02:27:34.593 31197 19338 I ReactNativeJS: Disconnected from DDP server.
12-23 02:27:34.599 31197 19338 I ReactNativeJS: <App /> render
12-23 02:27:34.599 31197 19338 I ReactNativeJS: Key home is already defined!
12-23 02:27:34.599 31197 19338 I ReactNativeJS: Key welcome is already defined!
12-23 02:27:34.599 31197 19338 I ReactNativeJS: Key loading is already defined!
12-23 02:27:34.599 31197 19338 I ReactNativeJS: Key root is already defined!
12-23 02:27:34.609 31197 19338 I ReactNativeJS: <Loading /> render
12-23 02:27:35.603 31197 19338 I ReactNativeJS: Disconnected from DDP server.
12-23 02:27:35.613 31197 19338 I ReactNativeJS: <App /> render
12-23 02:27:35.613 31197 19338 I ReactNativeJS: Key home is already defined!
12-23 02:27:35.613 31197 19338 I ReactNativeJS: Key welcome is already defined!
12-23 02:27:35.613 31197 19338 I ReactNativeJS: Key loading is already defined!
12-23 02:27:35.613 31197 19338 I ReactNativeJS: Key root is already defined!
12-23 02:27:45.599 31197 19338 I ReactNativeJS: Disconnected from DDP server.
12-23 02:27:45.616 31197 19338 I ReactNativeJS: <App /> render
12-23 02:27:45.616 31197 19338 I ReactNativeJS: Key home is already defined!
12-23 02:27:45.616 31197 19338 I ReactNativeJS: Key welcome is already defined!
12-23 02:27:45.616 31197 19338 I ReactNativeJS: Key loading is already defined!
12-23 02:27:45.616 31197 19338 I ReactNativeJS: Key root is already defined!

index.android.js

import { AppRegistry } from 'react-native'

import App from './app/App.js'

AppRegistry.registerComponent('RNapp', () => App)

App组件

export class App extends Component {

    constructor(props) {
        super(props);
    }

    componentWillReceiveProps(nextProps) {
        if (nextProps.status.connected == false) {
            Actions.loading();
        } else {
            if (nextProps.user !== null) {
                Actions.home();
            } else {
                Actions.welcome();
            }
        }
    }


    render() {
       console.log('<App /> render')
        return (
            <Router>
                <Scene key="root">
                    <Scene key="home" component={Home} title="Home" hideNavBar={true} />
                    <Scene key="welcome" component={Welcome} title="Welcome" hideNavBar={true} />
                    <Scene key="loading" component={Loading} title="Loading" hideNavBar={true} />
                    <Scene key="profile" component={Profile} title="Home" hideNavBar={true} />
                    <Scene key="history" component={History} title="Home" hideNavBar={true} />
                    <Scene key="search" component={Search} title="Home" hideNavBar={true} />
                </Scene>
            </Router>
        )       
    }

}


export default createContainer(() => {
  return {
    status: Meteor.status(),
    user: Meteor.user(),
    loggingIn: Meteor.loggingIn(),
  };
}, App);

最佳答案

警告不会造成任何伤害，但您可以通过在变量中定义场景然后将它们作为 prop 包含在路由器中来摆脱它们，如下所示:

const scenes = Actions.create(
  <Scene key="root">
    <Scene key="home" component={Home} title="Home" hideNavBar={true} />
    <Scene key="welcome" component={Welcome} title="Welcome" hideNavBar={true} />
    <Scene key="loading" component={Loading} title="Loading" hideNavBar={true} />
    <Scene key="profile" component={Profile} title="Home" hideNavBar={true} />
    <Scene key="history" component={History} title="Home" hideNavBar={true} />
    <Scene key="search" component={Search} title="Home" hideNavBar={true} />
  </Scene>
)

export class App extends Component {

  constructor(props) {
    super(props);
  }

  componentWillReceiveProps(nextProps) {
    if (nextProps.status.connected == false) {
      Actions.loading();
    } else {
      if (nextProps.user !== null) {
        Actions.home();
      } else {
        Actions.welcome();
      }
    }
  }


  render() {
    console.log('<App /> render')
    return (
      <Router scenes={scenes} />
    )
  }

}

参见 docs了解更多信息。

关于javascript - react-native-router-flux 警告 : Key is already defined，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/41354999/