React Native - 使用 AsyncStorage 将数据存储在另一个屏幕中

Question

我正在尝试使用 AsyncStorage 在我的应用程序中存储一些数据，但问题是每当我提交数据然后导航到第二个屏幕（应该存储数据的地方）时它是空的。

navigation button

SendOrder Screen

这是我的代码

SendOrder.js

import Settlement from './Settlement';

export default class SendOrder extends React.Component {

state = {
    text: '',
    storedValue: '',
}

onSave = async () => {
    const { text } = this.state

    try {
        await AsyncStorage.setItem(key, text);
        Alert.alert('Saved', 'Successful');
    } catch (error) {
        Alert.alert('Error', 'There was an error.')
    }
}

onChange = (text) => {
    this.setState({ text });
}

  render() {
    return (
      <View>
        <View>
            <Text>- Noter -</Text>
        </View>
        <View>
            <TextInput
                onChangeText = {this.onChange}
                value = { this.state.text }>
            </TextInput>
        </View>
        <TouchableOpacity onPress = { this.onSave }>
            <Text style = { styles.addButtonText }> + </Text>
        </TouchableOpacity>    
      </View>
    );
  }
}

Settlement.js

import SendOrder from './SendOrder';
const key = '@MyApp:key';

export default class Settlement extends React.Component {

    state = {
        text: '',
        storedValue: '',
    }

    componentWillMount() {
        this.onLoad();
    }

    onLoad = async () => {
        try {
            const storedValue = await AsyncStorage.getItem(key);
        } catch (error) {
            Alert.alert('Error', 'There was an error.')
        }
    }

  render() {
      const { storedValue, text } = this.state;
    return (
        <View>
            <Text>{storedValue}</Text>
            <View>
                <TouchableOpacity onPress = {this.onLoad}>
                    <Text>Load Data</Text>
                </TouchableOpacity>
            </View>
        </View>
    );
  }
}

Answer 1

你需要将storedValue存储到onLoad里面的状态，比如

onLoad = async () => {
    try {
        const storedValue = await AsyncStorage.getItem(key);
        this.setState({ storedValue });
    } catch (error) {
        Alert.alert('Error', 'There was an error.')
    }
}

希望对您有所帮助！

Answer 2

更改此行 " await AsyncStorage.setItem(key, text); " 到 " await AsyncStorage.setItem('key', 文本); " 密钥的名称应该是字符串，所以它应该用单引号引起来。

和改变这一行 “ const storedValue = await AsyncStorage.getItem(key); “到 " const storedValue = await AsyncStorage.getItem('key'); " 调用的设置键的名称应该是字符串，所以它应该在单引号中。

您设置的密钥不同，您获得的密钥也不同

React Native - 使用 AsyncStorage 将数据存储在另一个屏幕中

React Native - Using AsyncStorage to store data in another screen

javascript

react-native

asyncstorage