如何使的setState在陣營同步過程

Question

在我的應用程序，我需要轉換異步同步（即）一次的setState設置的值，然後我需要在後期調用

logChange(val) { 
    this.setState({ 
     fetchIntentReport: { 
      startDate: this.state.fetchIntentReport.startDate, 
      endDate: this.state.fetchIntentReport.endDate, 
      intents: val.split(','), 
     }, 
    }); 
    this.props.fetchIntentReports({ 
     startDate: this.state.fetchIntentReport.startDate, 
     endDate: this.state.fetchIntentReport.endDate, 
     intents: this.state.fetchIntentReport.intents, 
    }); 
} 

一旦獲取來自API的數據值設置爲意圖，那麼我需要通過REDX調用fetchIntentReports API調用。

Answer 1

我強烈建議不要強制進行同步呼叫。幸運的是，setState允許回調函數，所以你可以做到以下幾點：

logChange(val) { 
    var startDate = this.state.fetchIntentReport.startDate; 
    var endDate = this.state.fetchIntentReport.endDate; 
    var intents = val.split(','); 

    this.setState({ 
     fetchIntentReport: { 
      startDate, 
      endDate, 
      intents 
     } 
    },() => { 
     // if you need the updated state value, use this.state in this callback 
     // note: make sure you use arrow function to maintain "this" context 
     this.props.fetchIntentReports({ 
      startDate, 
      endDate, 
      intents 
     }) 
    ); 
}