reactjs - 道具 onChange 没有触发

Question

每当用户在选择编辑时输入一个值时，我都在努力输入一个值，它不会让我输入一个值。

我怀疑这应该与onChange方法有关，我不确定我应该做什么。我认为onChange方法是对的。

我读了一个与此类似的问题，但没有我正在寻找的解决方案。

PostList.js

import React, { Component } from 'react';
import Paper from '@material-ui/core/Paper';
import Button from '@material-ui/core/Button';
import Typography from '@material-ui/core/Typography';
import moment from 'moment';
import {connect} from 'react-redux';
import {DeletePost} from '../actions/';
import PostItem from './PostItem';
const Styles = {
    myPaper: {
        margin: '20px 0px',
        padding: '20px'
    }
}
class PostList extends Component{
    constructor(props){
        super(props);
        this.state ={
            isEditing:false,
            isEditingId:null
        }
    }
    // Return a new function. Otherwise the DeletePost action will be dispatch each
     // time the Component rerenders.
    removePost = (id) => () => {
        this.props.DeletePost(id);
    }
    // this will be onChange used for the <Editable component/>
    onChange = (e) => {
        e.preventDefault();
        this.setState({
            [e.target.title]: e.target.value
        })
    }

    formEditing = (id) => ()=> {
        this.setState({
            isEditingId: id
          });
    }

    render(){
        const {posts, editForm, isEditing, editChange} = this.props;
        return (
            <div>
                {posts.map((post, i) => (
                    <Paper key={post.id} style={Styles.myPaper}>
                    {/* {...post} prevents us from writing all of the properties out */}
                        <PostItem editChange={this.onChange} editForm={this.formEditing} isEditing={this.state.isEditingId === post.id} removePost={this.removePost} {...post} />
                    </Paper>
                ))}
            </div>
        )
    }
}
const mapDispatchToProps = (dispatch) => ({
    // Pass id to the DeletePost functions.
    DeletePost: (id) => dispatch(DeletePost(id))
});
export default connect(null, mapDispatchToProps)(PostList);

可编辑的.js

import React from 'react';
import Paper from '@material-ui/core/Paper';
import Button from '@material-ui/core/Button';
import Typography from '@material-ui/core/Typography';
import TextField from '@material-ui/core/TextField';

const Editable = (props) => (
    <div>
        <TextField
            id="outlined-name"
            label="Title"
            style={{width: 560}}
            name="title"
            value={props.editField}
            onChange={props.editChange}
            margin="normal"
            variant="outlined"/>

    </div>
)

export default Editable; 

PostItem.js

import React, { Component } from 'react';
import Paper from '@material-ui/core/Paper';
import Button from '@material-ui/core/Button';
import Typography from '@material-ui/core/Typography';
import moment from 'moment';
import Editable from './Editable';
const Styles = {
    myPaper: {
        margin: '20px 0px',
        padding: '20px'
    }
}
// editChange will passed in as an argument. So the <Editable/> component can 
//use it
const PostItem = ({ title, id,  removePost, createdAt, post_content, username, editForm, isEditing, editChange}) => {
    return(
         <div>
                <Typography variant="h6" component="h3">
                {/* if else teneray operator */}
                {isEditing ? (
                    <Editable editField={title} editChange={editChange}/>
                ): (
                    <div>
                        {title}
                    </div>    
                )}         
                </Typography>
                <Typography component="p">
                    {post_content}
                    <h5>
                        by: {username}</h5>
                    <Typography color="textSecondary">{moment(createdAt).calendar()}</Typography>
                </Typography>
                {!isEditing ? (
                    <Button variant="outlined" type="submit" onClick={editForm(id)}>
                        Edit
                    </Button>
                ):(
                    <Button variant="outlined" type="submit" onClick={editForm(null)}>
                        Update
                    </Button>
                )}
                <Button
                    variant="outlined"
                    color="primary"
                    type="submit"
                    onClick={removePost(id)}>
                    Remove
                </Button>
        </div>
    )
}
export default PostItem;

更新（）

我想保留当前的标题值而不是删除该值。

标签： reactjs

Answer 1

我认为您没有正确传递您的标题状态。将这些添加到您的状态以初始化为空：

this.state ={
     isEditing:false,
     isEditingId:null,
     title: ""
}

onChange 到这个

  onChange = (e) => {
        e.preventDefault();
        this.setState({
            title: e.target.value
        })
    }

PostItem到这个

const PostItem = ({ title, id,  removePost, createdAt, post_content, username, editForm, isEditing, editChange }) => {
    return(
         <div>
                <Typography variant="h6" component="h3">
                {/* if else teneray operator */}
                {isEditing ? (
                    <Editable editField={title} editChange={editChange}/>
                ): (
                    <div>
                        {title}
                    </div>    
                )}         
                </Typography>
                <Typography component="p">
                    {post_content}
                    <h5>
                        by: {username}</h5>
                    <Typography color="textSecondary">{moment(createdAt).calendar()}</Typography>
                </Typography>
                {!isEditing ? (
                    <Button variant="outlined" type="submit" onClick={editForm(id)}>
                        Edit
                    </Button>
                ):(
                    <Button variant="outlined" type="submit" onClick={editForm(null)}>
                        Update
                    </Button>
                )}
                <Button
                    variant="outlined"
                    color="primary"
                    type="submit"
                    onClick={removePost(id)}>
                    Remove
                </Button>
        </div>
    )
}
export default PostItem;

然后将标题作为道具传递给您的 PostItem，

例如

 <PostItem title={this.state.title} editChange={this.onChange} editForm={this.formEditing} isEditing={this.state.isEditingId === post.id} removePost={this.removePost} {...post} />

更新

改变这个

<Editable editField={myTitle} editChange={editChange}/>

to（这使得标题附加在值中，而您仍然可以随意编辑值以改进它）它的行为有点错误或奇怪，但它可以工作。

 <Editable editField={title} editChange={editChange}/>