React 入门学习笔记整理（八）—— todoList

APP.js

import React, { Component,createRef,Fragment} from 'react';
import Todos from './components/todos';
import Footer from './components/footer';
import './main.css';
class App extends Component {
    constructor(props){
        super(props);
        this.state ={
            todoList:[],
            view:'all'
        };
        this.todoInput = createRef();
    }

    //添加todoList
    addTodo = (ev) => {
        let {value} = this.todoInput.current;
        if (ev.keyCode !== 13 || !value) return;
        let {todoList} = this.state;
        this.setState({
            todoList:[
                {
                    id:Math.random(),
                    content:value,
                    hasCompleted:false
                },
                ...todoList
            ]
        },()=>{
            this.todoInput.current.value = '';
        })
    };

    deleteTodo = (id)=>{
        let {todoList} = this.state;
        todoList = todoList.filter((item)=>{
            return item.id !== id;
        });
        this.setState({
            todoList:todoList
        })
    };

    toggleTodo = (id)=>{
        let {todoList} = this.state;
        todoList = todoList.map((item)=>{
            if(item.id === id){
                item.hasCompleted = !item.hasCompleted;
            }
            return item;
        });
        this.setState({
            todoList:todoList
        })
    };
    toggleAll =(ev)=>{
        let {todoList} = this.state;
        todoList = todoList.map((item)=>{
            item.hasCompleted = ev.target.checked;
            return item;
        });
        this.setState({
            todoList:todoList
        })
    };
  changeTodoContent = (id,content) =>{
      let {todoList} = this.state;
      todoList = todoList.map((item)=>{
          if(item.id === id){
              item.content =content;
          }
          return item;
      });
      this.setState({
          todoList:todoList
      })
  };
  clearComponent = ()=>{
      let {todoList} = this.state;
      todoList = todoList.filter((item)=>{
          return !item.hasCompleted;
      });
      this.setState({
          todoList:todoList
      })
  };
   changeView = (view) =>{
        this.setState({
            view:view
        })
   };
  render() {
        let {todoList ,view} = this.state;
        let selectAll = todoList.find((item)=>item.hasCompleted === false);
        let clearComponented = todoList.find((item)=>item.hasCompleted);
        let leftTodoNum = 0; //剩下未完成的条数
        let showTodoList = todoList.filter((item)=>{
            if(!item.hasCompleted) leftTodoNum++;
            switch(view){
                case 'active':
                    return !item.hasCompleted;
                case 'completed':
                    return item.hasCompleted;
                case 'all':
                default:
                    return true;
            }
        });

        let todos = showTodoList.map((item)=>{
            return (
                <Todos key={item.id}
                       {...{
                           id:item.id,
                           content:item.content,
                           deleteTodo:this.deleteTodo,
                           hasCompleted:item.hasCompleted,
                           toggleTodo:this.toggleTodo,
                           changeTodoContent:this.changeTodoContent
                     }}
                 />
            )
        });

    return (
      <div>
          <header className="header">
              <h1>todos</h1>
              {/*输入框*/}
              <input type="text"
                     className="new-todo"
                     placeholder="type something here"
                     onKeyDown={this.addTodo}
                     ref={this.todoInput}
              />
          </header>
          { todoList.length>0 && (
              <Fragment>
                  <section className="main">
                      {/*全选按钮*/}
                      <input type="checkbox"
                             className="toggle-all"
                             checked = {!selectAll && todoList.length}
                             onChange={this.toggleAll}
                      />
                      <ul className="todo-list">
                          {todos}
                      </ul>
                  </section>
                  <Footer
                      {...{
                        showClearBtn:clearComponented,
                        clearComponent:this.clearComponent,
                        view,
                        changeView:this.changeView,
                        leftTodoNum
                      }}
                  />
              </Fragment>)
          }
      </div>
    );
  }
}

export default App;

todos.js

import React, { Component,createRef } from 'react';

export default class extends Component{
    constructor(props){
        super(props);
        this.state = {
            inEdit:false
        }
        this.editInput = createRef();
    }

    inEdit = () =>{
        this.setState({
            inEdit:true
        },()=>{
            this.editInput.current.focus();
            this.editInput.current.value = this.props.content;
        })
    };
    commitContent = () =>{
        let id = this.props.id;
        let content = this.editInput.current.value;
        if(content){
            this.props.changeTodoContent(id,content);
        }else{
            this.props.deleteTodo(id);
        }
        this.editInput.current.value = '';
    };
    //失去焦点时，将input框输入的值，传给标签
    onBlur = () =>{
        //如果已经不处于编辑状态，就不需要继续执行了
        if(!this.state.inEdit) return;
        this.setState({
            inEdit:false
        },()=>{
            this.commitContent();
        })
    };
    onKeyDown = (ev) =>{
        if(ev.keyCode === 27 || ev.keyCode === 13) {
            this.setState({
                inEdit:false
            })
        }
        if(ev.keyCode === 13) this.commitContent();
    };
    render(){
        let {
            content,
            deleteTodo,
            id,
            hasCompleted,
            toggleTodo
        } = this.props;

        let className =  this.state.inEdit ? 'editing':'';
        className = hasCompleted? className +' completed':className;
        return (
            <li className={className}>
                <div className="view">
                    {/*勾选按钮*/}
                    <input type="checkbox"
                           className="toggle"
                           checked={hasCompleted}
                           onChange={()=>toggleTodo(id)}
                    />
                    {/*todo内容*/}
                    <label onDoubleClick={this.inEdit}>{content}</label>
                    {/*删除按钮*/}
                    <button className="destroy" onClick={()=>deleteTodo(id)}></button>
                </div>
                {/*编辑按钮*/}
                <input type="text"
                       className="edit"
                       ref = {this.editInput}
                       onBlur={this.onBlur}
                       onKeyDown={this.onKeyDown}
                />
            </li>
        )
    }
}

footer.js

import React from 'react';

export default function(props){

  let {
    clearCompleted,
    showClearButton,
    changeView
  } = props;

  return (
    <footer className="footer">
      <span className="todo-count">
        <strong> 8 </strong>
        <span>item left</span>
      </span>
      <ul className="filters">
        <li>
          <a
            className="selected"
          >All</a>

        </li>
        <li>
          <a
            className="selected"
          >Active</a>

        </li>
        <li>
          <a
          >Completed</a>

        </li>
      </ul>
      {/* 清除完成按钮 */}
      {showClearButton && (
        <button
          className="clear-completed"
          onClick={clearCompleted}
        >
          clear all completed
        </button>
      )}

    </footer>
  )
}

main.css

html,
body {
    margin: 0;
    padding: 0;
}

button {
    margin: 0;
    padding: 0;
    border: 0;
    background: none;
    font-size: 100%;
    vertical-align: baseline;
    font-family: inherit;
    font-weight: inherit;
    color: inherit;
    -webkit-appearance: none;
    appearance: none;
    -webkit-font-smoothing: antialiased;
    -moz-font-smoothing: antialiased;
    font-smoothing: antialiased;
}

body {
    font: 14px 'Helvetica Neue', Helvetica, Arial, sans-serif;
    line-height: 1.4em;
    background: #f5f5f5;
    color: #4d4d4d;
    min-width: 230px;
    max-width: 550px;
    margin: 0 auto;
    -webkit-font-smoothing: antialiased;
    -moz-font-smoothing: antialiased;
    font-smoothing: antialiased;
    font-weight: 300;
}

button,
input[type="checkbox"] {
    outline: none;
}

.hidden {
    display: none;
}

.todoapp {
    background: #fff;
    margin: 130px 0 40px 0;
    position: relative;
    box-shadow: 0 2px 4px 0 rgba(0, 0, 0, 0.2),
    0 25px 50px 0 rgba(0, 0, 0, 0.1);
}

.todoapp input::-webkit-input-placeholder {
    font-style: italic;
    font-weight: 300;
    color: #e6e6e6;
}

.todoapp input::-moz-placeholder {
    font-style: italic;
    font-weight: 300;
    color: #e6e6e6;
}

.todoapp input::input-placeholder {
    font-style: italic;
    font-weight: 300;
    color: #e6e6e6;
}

.todoapp h1 {
    position: absolute;
    top: -155px;
    width: 100%;
    font-size: 100px;
    font-weight: 100;
    text-align: center;
    color: rgba(175, 47, 47, 0.15);
    -webkit-text-rendering: optimizeLegibility;
    -moz-text-rendering: optimizeLegibility;
    text-rendering: optimizeLegibility;
}

.new-todo,
.edit {
    position: relative;
    margin: 0;
    width: 100%;
    font-size: 24px;
    font-family: inherit;
    font-weight: inherit;
    line-height: 1.4em;
    border: 0;
    outline: none;
    color: inherit;
    padding: 6px;
    border: 1px solid #999;
    box-shadow: inset 0 -1px 5px 0 rgba(0, 0, 0, 0.2);
    box-sizing: border-box;
    -webkit-font-smoothing: antialiased;
    -moz-font-smoothing: antialiased;
    font-smoothing: antialiased;
}

.new-todo {
    padding: 16px 16px 16px 60px;
    border: none;
    background: rgba(0, 0, 0, 0.003);
    box-shadow: inset 0 -2px 1px rgba(0,0,0,0.03);
}

.main {
    position: relative;
    z-index: 2;
    border-top: 1px solid #e6e6e6;
}

label[for='toggle-all'] {
    display: none;
}

.toggle-all {
    position: absolute;
    top: -55px;
    left: -12px;
    width: 60px;
    height: 34px;
    text-align: center;
    border: none; /* Mobile Safari */
}

.toggle-all:before {
    content: '❯';
    font-size: 22px;
    color: #e6e6e6;
    padding: 10px 27px 10px 27px;
}

.toggle-all:checked:before {
    color: #737373;
}

.todo-list {
    margin: 0;
    padding: 0;
    list-style: none;
}

.todo-list li {
    position: relative;
    font-size: 24px;
    border-bottom: 1px solid #ededed;
}

.todo-list li:last-child {
    border-bottom: none;
}

.todo-list li.editing {
    border-bottom: none;
    padding: 0;
}

.todo-list li.editing .edit {
    display: block;
    width: 506px;
    padding: 13px 17px 12px 17px;
    margin: 0 0 0 43px;
}

.todo-list li.editing .view {
    display: none;
}

.todo-list li .toggle {
    text-align: center;
    width: 40px;
    /* auto, since non-WebKit browsers doesn't support input styling */
    height: auto;
    position: absolute;
    top: 0;
    bottom: 0;
    margin: auto 0;
    border: none; /* Mobile Safari */
    -webkit-appearance: none;
    appearance: none;
}

.todo-list li .toggle:after {
    content: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="40" height="40" viewBox="-10 -18 100 135"><circle cx="50" cy="50" r="50" fill="none" stroke="#ededed" stroke-width="3"/></svg>');
}

.todo-list li .toggle:checked:after {
    content: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="40" height="40" viewBox="-10 -18 100 135"><circle cx="50" cy="50" r="50" fill="none" stroke="#bddad5" stroke-width="3"/><path fill="#5dc2af" d="M72 25L42 71 27 56l-4 4 20 20 34-52z"/></svg>');
}

.todo-list li label {
    white-space: pre-line;
    word-break: break-all;
    padding: 15px 60px 15px 15px;
    margin-left: 45px;
    display: block;
    line-height: 1.2;
    transition: color 0.4s;
}

.todo-list li.completed label {
    color: #d9d9d9;
    text-decoration: line-through;
}

.todo-list li .destroy {
    display: none;
    position: absolute;
    top: 0;
    right: 10px;
    bottom: 0;
    width: 40px;
    height: 40px;
    margin: auto 0;
    font-size: 30px;
    color: #cc9a9a;
    margin-bottom: 11px;
    transition: color 0.2s ease-out;
}

.todo-list li .destroy:hover {
    color: #af5b5e;
}

.todo-list li .destroy:after {
    content: '×';
}

.todo-list li:hover .destroy {
    display: block;
}

.todo-list li .edit {
    display: none;
}

.todo-list li.editing:last-child {
    margin-bottom: -1px;
}

.footer {
    color: #777;
    padding: 10px 15px;
    height: 20px;
    text-align: center;
    border-top: 1px solid #e6e6e6;
}

.footer:before {
    content: '';
    position: absolute;
    right: 0;
    bottom: 0;
    left: 0;
    height: 50px;
    overflow: hidden;
    box-shadow: 0 1px 1px rgba(0, 0, 0, 0.2),
    0 8px 0 -3px #f6f6f6,
    0 9px 1px -3px rgba(0, 0, 0, 0.2),
    0 16px 0 -6px #f6f6f6,
    0 17px 2px -6px rgba(0, 0, 0, 0.2);
}

.todo-count {
    float: left;
    text-align: left;
}

.todo-count strong {
    font-weight: 300;
}

.filters {
    margin: 0;
    padding: 0;
    list-style: none;
    position: absolute;
    right: 0;
    left: 0;
}

.filters li {
    display: inline;
}

.filters li a {
    color: inherit;
    margin: 3px;
    padding: 3px 7px;
    text-decoration: none;
    border: 1px solid transparent;
    border-radius: 3px;
}

.filters li a.selected,
.filters li a:hover {
    border-color: rgba(175, 47, 47, 0.1);
}

.filters li a.selected {
    border-color: rgba(175, 47, 47, 0.2);
}

.clear-completed,
html .clear-completed:active {
    float: right;
    position: relative;
    line-height: 20px;
    text-decoration: none;
    cursor: pointer;
    position: relative;
}

.clear-completed:hover {
    text-decoration: underline;
}

.info {
    margin: 65px auto 0;
    color: #bfbfbf;
    font-size: 10px;
    text-shadow: 0 1px 0 rgba(255, 255, 255, 0.5);
    text-align: center;
}

.info p {
    line-height: 1;
}

.info a {
    color: inherit;
    text-decoration: none;
    font-weight: 400;
}

.info a:hover {
    text-decoration: underline;
}

/*
	Hack to remove background from Mobile Safari.
	Can't use it globally since it destroys checkboxes in Firefox
*/
@media screen and (-webkit-min-device-pixel-ratio:0) {
    .toggle-all,
    .todo-list li .toggle {
        background: none;
    }

    .todo-list li .toggle {
        height: 40px;
    }

    .toggle-all {
        -webkit-transform: rotate(90deg);
        transform: rotate(90deg);
        -webkit-appearance: none;
        appearance: none;
    }
}

@media (max-width: 430px) {
    .footer {
        height: 50px;
    }

    .filters {
        bottom: 10px;
    }
}

用路由实现跳转

App.js

   let {location:{pathname}} = this.props;

  switch(pathname){
                case '/active':
                    return !item.hasCompleted;
                case '/completed':
                    return item.hasCompleted;
                case '/':
                default:
                    return true;
            }

 <Link to="/active" className={pathname === '/active'?"selected":''}>Active</Link>