Doubts about the reducer code of react getting started with TODO List

problem description

TODO List case, delete action data of list and do not re-render UI

the environmental background of the problems and what methods you have tried

redux-devtools-extension plug-in, check the data changes after action is triggered, and find that everything is normal.

related codes

reducer

import React, {Fragment } from "react"
import {connect} from "react-redux"


const TodoList = (props) => {
  const {list, inputValue, handleClick, handleDelete, handleInputChange} = props
    return (
      <Fragment>
        <input onChange={handleInputChange} value={inputValue}></input>
        <button onClick={handleClick}></button>
        <ul>
          {
            list.map((item, index) => {
              return <li key={index} onClick={() => {handleDelete(index)}}>{item}</li>
            })
          }
        </ul>
      </Fragment>
    )
}

const mapStateToProps = (state) => {
  return {
    inputValue: state.inputValue,
    list: state.list
  }
}

const mapDispatchToProps = (dispatch) => {
  return {
    handleInputChange(e) {
      const value = e.target.value
      const action = {
        type: "change_input_value",
        value
      }
      dispatch(action)
    },
    handleClick(){
      const action = {
        type: "submit_input_value"
      }
      dispatch(action)
    }, 
    handleDelete(index){      
      const action = {
        type: "delete",
        index
      }
      dispatch(action)
    }
  }
}

export default connect(mapStateToProps, mapDispatchToProps)(TodoList)

what result do you expect? What is the error message actually seen?

there are no errors, but after clicking on the newly added list item, the data state changes, but the page UI does not change.

Mar.13,2022

There is a problem with the writing of

reducer. The new state is returned and the old state is modified at the same time.

return {
    ...state,
    list: [
        ...state.list,
        action.value
    ]
}

the problem lies in defaultValue. List is all the same value, and react uses shallow comparison

.
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1c275b6-54efb.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1c275b6-54efb.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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