stateful class component eventListener

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Fri Feb 18 2022 05:46:14 GMT+0000 (Coordinated Universal Time)

Saved by @Rubel #react.js

import React, { Component } from "react";
import NewTask from "../Presentational/NewTask";
import TasksList from "../Presentational/TasksList";

export default class AppClass extends Component {
  constructor(props) {
    super(props);
    this.state = {
      newTask: {},
      allTasks: []
    };
    this.handleChange = this.handleChange.bind(this);
    this.handleSubmit = this.handleSubmit.bind(this);
    this.handleDelete = this.handleDelete.bind(this);
  }

  handleChange({ target }){
    const { name, value } = target;
    this.setState((prevState) => ({
      ...prevState,
      newTask: {
        ...prevState.newTask,
        [name]: value,
        id: Date.now()
      }
    }));
  }

  handleSubmit(event){
    event.preventDefault();
    if (!this.state.newTask.title) return;
    this.setState((prevState) => ({
      allTasks: [prevState.newTask, ...prevState.allTasks],
      newTask: {}
    }));
  }

  handleDelete(taskIdToRemove){
    this.setState((prevState) => ({
      ...prevState,
      allTasks: prevState.allTasks.filter((task) => task.id !== taskIdToRemove)
    }));
  }

  render() {
    return (
      <main>
        <h1>Tasks</h1>
        <NewTask
          newTask={this.state.newTask}
          handleChange={this.handleChange}
          handleSubmit={this.handleSubmit}
        />
        <TasksList
          allTasks={this.state.allTasks}
          handleDelete={this.handleDelete}
        />
      </main>
    );
  }
}

statefull class component for eventListener handling

https://www.codecademy.com/courses/react-101/lessons/the-state-hook/exercises/lesson-review

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