react入门:todo应用

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta http-equiv="X-UA-Compatible" content="ie=edge" />
    <title>To-Do</title>
    <style>
      .to-do-page {
        position: absolute;
        top: 0;
        right: 0;
        left: 0;
        bottom: 0;
        margin: auto;
         400px;
        height: 400px;
      }
      header {
        font-size: 30px;
        font-weight: 200;
        font-family: fantasy;
        text-align: center;
        margin-bottom: 10px;
      }
      main {
        border: 1px solid #dedede;
        border-radius: 10px;
        min-height: 200px;
      }
      footer {
        text-align: center;
        margin-top: 10px;
      }
      .add-form {
        height: 40px;
        background: #fff;
        border: 4px solid rgb(74, 179, 74);
      }
      .add-ipt {
        height: 36px;
         300px;
        border: none;
        outline: medium;
        padding-left: 20px;
      }
      .add-btn {
        height: 40px;
         70px;
        background: rgb(74, 179, 74);
        color: white;
        border: none;
        font-weight: bold;
        outline: medium;
      }
      .list-item {
        margin: 10px;
        font-size: 16px;
        font-weight: bold;
      }
      .list-item input {
        height: 25px;
        font-weight: bold;
        opacity: 0.6;
        padding-left: 10px;
      }
      .list-item:hover {
        cursor: pointer;
      }
      .operate-area span {
        display: inline-block;
        color: #7676d9;
        margin-left: 10px;
      }
      .operate-area span:hover {
        cursor: pointer;
      }
    </style>
  </head>

  <body>
    <div id="app"></div>
    <script src="https://cdn.staticfile.org/react/16.4.0/umd/react.development.js"></script>
    <script src="https://cdn.staticfile.org/react-dom/16.4.0/umd/react-dom.development.js"></script>
    <script src="https://cdn.staticfile.org/babel-standalone/6.26.0/babel.min.js"></script>
    <script type="text/babel">
      //  总页面
      class ToDoPage extends React.Component {
        render() {
          return (
            <div className='to-do-page'>
              <Header />
              <Main />
              <Footer />
            </div>
          );
        }
      }
      //  页头
      class Header extends React.Component {
        render() {
          return <header>To-Do</header>;
        }
      }
      // 内容
      class Main extends React.Component {
        render() {
          return (
            <main>
              <ToDoBox />
            </main>
          );
        }
      }
      //  页脚
      class Footer extends React.Component {
        render() {
          return <footer> ©2019 仅做示例使用</footer>;
        }
      }
      class ToDoBox extends React.Component {
        constructor(props) {
          super(props);
          this.state = {
            toDoList: [
              {
                id: 0,
                content: '学习'
              },
              {
                id: 1,
                content: '晚餐'
              }
            ]
          };
          this.update = this.update.bind(this);
        }
        //  更新toDoList对象
        update(data) {
          this.setState({
            toDoList: data
          });
        }
        render() {
          return (
            <div>
              <AddAffairForm toDoList={this.state.toDoList} update={this.update} />
              <ToDoList toDoList={this.state.toDoList} update={this.update} />
            </div>
          );
        }
      }
      // 添加表单
      class AddAffairForm extends React.Component {
        constructor(props) {
          super(props);
          this.state = {
            affair: ''
          };
          this.toDoList = this.props.toDoList;
          this.handleChange = this.handleChange.bind(this);
          this.addToDoList = this.addToDoList.bind(this);
        }
        handleChange(e) {
          this.setState({
            affair: e.target.value
          });
        }
        addToDoList(e) {
          e.preventDefault();
          if (this.state.affair.trim().length < 1) {
            alert('不能不输入哦!');
          } else {
            this.toDoList = [...this.toDoList, { id: this.toDoList.length, content: this.state.affair }];
            this.props.update && this.props.update(this.toDoList);
            this.setState({
              affair: ''
            });
          }
        }
        render() {
          let addAffairForm = (
            <form onSubmit={this.addToDoList} className='add-form'>
              <input
                className='add-ipt'
                type='text'
                placeholder='今天做点什么呢?'
                value={this.state.affair}
                onChange={this.handleChange}
                required
              />
              <input type='submit' value='加入计划' onSubmit={this.addToDoList} className='add-btn' />
            </form>
          );
          return addAffairForm;
        }
      }
      //  列表
      class ToDoList extends React.Component {
        constructor(props) {
          super(props);
          this.delete = this.delete.bind(this);
          this.update = this.update.bind(this);
        }
        delete(id) {
          let toDoList = [...this.props.toDoList];
          toDoList = toDoList.filter(item => item.id !== id);
          this.props.update && this.props.update(toDoList);
        }
        update(data) {
          let toDoList = [...this.props.toDoList];
          toDoList.map(item => {
            if (item.id === data.id) {
              item.content = data.content;
            }
          });
          this.props.update && this.props.update(toDoList);
        }
        render() {
          return (
            <ul className='list'>
              {this.props.toDoList.map((item, index) => {
                return <ToDoListItem toDoListItem={item} key={item.id} delete={this.delete} update={this.update} />;
              })}
            </ul>
          );
        }
      }
      //  列表项
      class ToDoListItem extends React.Component {
        constructor(props) {
          super(props);
          this.state = {
            item: Object.assign({}, this.props.toDoListItem),
            isDisplay: false,
            isEdit: false
          };
          this.toggleDisplay = this.toggleDisplay.bind(this);
          this.handleChange = this.handleChange.bind(this);
          this.cancelEdit = this.cancelEdit.bind(this);
          this.handleEdit = this.handleEdit.bind(this);
          this.finishAffair = this.finishAffair.bind(this);
          this.confirmEdit = this.confirmEdit.bind(this);
        }
        toggleDisplay(e) {
          this.setState({
            isDisplay: !this.state.isDisplay
          });
        }
        handleChange(e) {
          const item = this.state.item;
          item.content = e.target.value;
          this.setState({
            item: item
          });
        }
        cancelEdit() {
          const item = Object.assign({}, this.props.toDoListItem);
          this.setState({
            item: item,
            isEdit: !this.state.isEdit
          });
        }
        handleEdit() {
          this.setState({
            isEdit: !this.state.isEdit
          });
        }
        finishAffair(e) {
          e.stopPropagation();
          this.props.delete && this.props.delete(this.state.item.id);
        }
        confirmEdit(e) {
          this.props.update && this.props.update(this.state.item);
          this.handleEdit();
        }
        render() {
          let todoListItem = null;
          if (this.state.isEdit) {
            todoListItem = (
              <li className='list-item'>
                <input value={this.state.item.content} placeholder='请输入' onChange={this.handleChange} />
                <span className='operate-area'>
                  <span onClick={this.confirmEdit}>确定</span>
                  <span onClick={this.cancelEdit}>取消</span>
                </span>
              </li>
            );
          } else {
            todoListItem = (
              <li className='list-item' onClick={this.toggleDisplay}>
                {this.props.toDoListItem.content}
                <span
                  style={this.state.isDisplay ? { display: 'inline-block' } : { display: 'none' }}
                  className='operate-area'
                >
                  <span onClick={this.handleEdit}>修改</span>
                  <span onClick={this.finishAffair}>完成</span>
                </span>
              </li>
            );
          }
          return todoListItem;
        }
      }
      const app = document.getElementById('app');
      ReactDOM.render(<ToDoPage />, app);
    </script>
  </body>
</html>

原文地址:https://www.cnblogs.com/yejingping/p/11200873.html