react-state

问题 A React.js warning was thrown: IndexPage: It is not recommended to assign props directly to state because updates to props won't be reflected in state. In most cases, it is better to use props directly. I had the following code: class IndexPage extends React.Component<IProps, IState> { constructor(props) { super(props) this.state = props } } But, when I have changed my code to: class IndexPage extends React.Component<IProps, IState> { constructor(props) { super(props) this.state = {...props}

问题 I need a solution for radio buttons, but the options array which is the main array is outside the class component. In this case, I will get OPTIONS array items through props but not hardcoded. How is it possible for me to Pass props outside class component Make OPTIONS state object and then pass it to checkboxes, which is inside state. import React, { Component } from "react"; import Checkbox from "./Checkbox"; const OPTIONS = ["One", "Two", "Three"]; class App extends Component { state = {

问题 I need a solution for radio buttons, but the options array which is the main array is outside the class component. In this case, I will get OPTIONS array items through props but not hardcoded. How is it possible for me to Pass props outside class component Make OPTIONS state object and then pass it to checkboxes, which is inside state. import React, { Component } from "react"; import Checkbox from "./Checkbox"; const OPTIONS = ["One", "Two", "Three"]; class App extends Component { state = {

问题 I have a function called addFunc in my main Class. This class calls the RenderItem function to display a list of items. Each item has an onClick that should execute the addFunc function. I am unable to call the addFunc function from within my RenderItem function because they are in different components. How do I get past this? This is a summary of my code: const selectedData = [] class Search extends Component { constructor(props) { super(props); this.addFunc = this.addFunc.bind(this); }

问题 I have a list of results, and each time I click on a result, it calls my addFunc function to add that particular result's details as an object in the selectedData list. Currently, this works when I console.log my selectedData list. What I want to do is display my selectedData list, and each time a result is clicked, the object will be added to the list, and I want that to be reflected on my screen. I believe I have to use state to do this, but I am not very sure how to. Thank you for your

问题 i am getting error at this.setState({ Url: resp.data.Url }); in GETAPI TypeError: Cannot read property 'setState' of undefined.. Please suggest. The GETAPI is basically used to render the data from the API. My use-case is to store all the URLs in state and pass it to DownloadButton component. I need this URL to download the required data. The hirerachy of code is invokeGetReport which will give all the reports in array. I have looped in and invoked invokeGetReportDetails method. Under

问题 I have a form where user can generate new inputs to the form he wants to submit, however i am stuck on handling the values of the new generated inputs as i need to store them in the state . My code const [supply_detail_data,setSupply_detail_data]=React.useState({ suppCashDetail:[{text : [],val:[]}] }); const addNewSuppDetailInput = () => { setSupply_detail_data( {suppCashDetail: [...supply_detail_data.suppCashDetail,{text : [],val:[]}]} ) } function supply_detail_handler(event){ // should

问题 In my react native 0.59.9 app, the App class has 2 states which may be updated by child components. class App extends React.Component { state = { group_id: this.props.navigation.state.params.data.group_id, result: this.props.navigation.state.params.data.result, }; updateGroup = (group_id) => { console.log("In updateGroup : ", group_id); this.setState({group_id:group_id}); }; updateToken = (token) => { console.log("In updateToken : ", token); this.setState({result: token}); }; const

问题 In my react native 0.59.9 app, the App class has 2 states which may be updated by child components. class App extends React.Component { state = { group_id: this.props.navigation.state.params.data.group_id, result: this.props.navigation.state.params.data.result, }; updateGroup = (group_id) => { console.log("In updateGroup : ", group_id); this.setState({group_id:group_id}); }; updateToken = (token) => { console.log("In updateToken : ", token); this.setState({result: token}); }; const

问题 How can I dynamically set the name of the array in state, to get it from state. onCheckBoxItemClickList(e, value, path) { console.log(e.target.checked) if (e.target.checked) { //append to array this.setState({ [path]: this.state.[path].concat([value]) }) } else { //remove from array this.setState({ [path]: this.state.[path].filter(function (val) { return val !== value }) }) } } I know how to dynamically set and get a key in state, but when I try and do [path]: this.state.[path].concat([value]