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当显示数组时,React Native post请求会导致无限循环

[英]React Native post request causes infinite loop when displaying array

I am navigating to this 'History' tab from a side menu in React Native Navigation. 我正在从React Native Navigation的侧边菜单导航到此“历史记录”选项卡。 Got a username for which I get all the 'bookings' made, but I can see in the warning tab that there are countless requests being made even after the component has been mounted, so there's an infinite loop probably caused by setState. 有一个用户名,我得到了所有'预订',但我可以在警告标签中看到,即使在组件安装后仍有无数的请求,因此可能由setState引起无限循环。 Where should I call getHistory(), as in to make only one request, unless of course the component is reloaded. 我应该在哪里调用getHistory(),因为只有一个请求,除非组件被重新加载。 Thank you! 谢谢!

constructor(props){
        super(props);
        this.state = {
            loggedUser: 'none',
            bookingsInfo: []
        }
    }

    getData = async () => {
        try {
          const value = await AsyncStorage.getItem('loggedUser')
          if(value !== null) {
            this.setState({
                loggedUser: value
            })
          }
        } catch(e) {
            console.error(e);
        }
    }

    getHistory() {
            fetch('https://porsche.e-twow.uk/reactnative/istoric.php', {
                method: 'POST',
                headers: {
                    Accept: 'application/json',
                    'Content-Type': 'application/json',
                    'Cache-Control': 'no-cache, no-store'
                },
                body: JSON.stringify({
                    username: this.state.loggedUser
                })
            })
            .then((response) => response.json())
            .then((data) => {
                this.setState({
                    bookingsInfo: data
                });
            })
            .catch((error) => {
                console.error(error);
            });
    }

    componentDidMount() {
        this.getData();
    }

    render() {
        this.getHistory();
        return (
            <View style={styles.view}>
                <ScrollView style={styles.scrollView}>
                    {
                        this.getHistory()
                    }
                    {
                        this.state.bookingsInfo ? this.state.bookingsInfo.map((item, index) => {
                            return (
                                <View style={styles.mainButton} key={item.id_scooter}>
                                    <Text style={styles.mainButtonText}>Scooter-ul {item.id_scooter}</Text>
                                    <Text style={styles.mainButtonText}>Data start: {item.start}</Text>
                                    <Text style={styles.mainButtonText}>Data final: {item.end}</Text>
                                </View>
                            )
                        }) : null
                    }
                </ScrollView>

                <Footer/>
            </View>
        );
    }
}

you are setting state in render.Calling setState here makes your component a contender for producing infinite loops. 你在render中设置状态。在这里调用setState使你的组件成为产生无限循环的竞争者。 place getHistory in componentDidMount . 在componentDidMount中放置getHistory。

  componentDidMount() {
   this.getHistory();
 }

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