在React中構建一個待辦事項應用程式，使用過濾器，但需要一種方法來確保“完成”按鈕只洗掉一個任務而不是兩個

我是學習反應的新手，所以我按照本教程 https://developer.mozilla.org/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_components創建了一個待辦事項應用程式，然后對其進行了調整以符合要求我正在做的專案。一切都按應有的方式作業，除非我從關聯方洗掉（完成）事物，它也會從我的主要方洗掉它。我理解為什么會發生這種情況的一般概念（我的代碼中沒有兩個單獨的串列），只是不確定如何在不洗掉我已有的過濾器的情況下修復它。我曾嘗試為這些任務實施一個單獨的串列，但只是不了解如何去做。

添加 CodeSandBox 以獲得更多背景關系：https ://codesandbox.io/s/hungry-sky-5f482?file =/ src/index.js 檢查任務專案，然后查看您在“顯示關聯任務”中檢查的專案。問題是在助理端完成任務也在“顯示所有任務”端完成。

應用程式.js

const FILTER_MAP = {
  All: () => true,
  Associate: task => task.checked 
};
const FILTER_NAMES = Object.keys(FILTER_MAP);

function App(props) {

  const [tasks, setTasks] = useState(props.tasks);
  const [filter, setFilter] = useState('All');

  function toggleTaskChecked(id) {
    const updatedTasks = tasks.map(task => {
      if (id === task.id) {
        return {...task, checked: !task.checked}
      }
      return task;
    });
    setTasks(updatedTasks);
  }

  function completeTask(id) {
    const remainingTasks = tasks.filter(task => id !== task.id);
    setTasks(remainingTasks);
  }

  const taskList = tasks
    .filter(FILTER_MAP[filter])
    .map(task => (
      <Todo
        id={task.id}
        name={task.name}
        checked={task.checked}
        key={task.id}
        toggleTaskChecked={toggleTaskChecked}
        completeTask={completeTask}
      />
    ));

  const filterList = FILTER_NAMES.map(name => (
    <FilterButton
    key={name}
    name={name}
    isPressed={name === filter}
    setFilter={setFilter}
  />
  ));

  function addTask(name) {
    const newTask = { id: "todo-"   nanoid(), name: name, checked: false };
    setTasks([...tasks, newTask]);
  }

  return (
    <div className="app">
      <h1 className = "tasks-header">Task Tracker</h1>
      <Form addTask={addTask}/>
      <div className="list-buttons">
        {filterList}
      </div>
      <ul
        role="list"
        className="todo-list"
        aria-labelledby="list-heading"
      >
        {taskList}
      </ul>
    </div>
  );

}

export default App

Todo.js

export default function Todo(props) {

  return (
    <li className="todo stack-small">
      <div className="c-cb">
        <input id={props.id} 
        type="checkbox" 
        defaultChecked={props.checked}
        onChange={() => props.toggleTaskChecked(props.id)} 
        />
        <label className="todo-label" htmlFor="todo-0">
          {props.name}
        </label>
      </div>
      <div className="btn-group">
        <button type="button" 
        className="complete-button"
        onClick={() => props.completeTask(props.id)}
        >
          Complete 
        </button>
      </div>
    </li>
  );
  }

index.js

const DATA = [
  { id: "todo-0", name: "Brush Teeth", checked: false },
  { id: "todo-1", name: "Make Dinner", checked: false },
  { id: "todo-2", name: "Walk Dog", checked: false },
  { id: "todo-3", name: "Run Reports", checked: false },
  { id: "todo-4", name: "Visit Mom", checked: false },
  { id: "todo-5", name: "Aerobics", checked: false },
  { id: "todo-6", name: "Project", checked: false },
  { id: "todo-7", name: "Lecture", checked: false },
  { id: "todo-8", name: "Have Lunch", checked: false }
];

ReactDOM.render(
  <React.StrictMode>
    <App tasks={DATA}/>
  </React.StrictMode>,
  document.getElementById('root')
);

過濾按鈕.js

function FilterButton(props) {
    return (
      <button
        type="button"
        className="toggle-btn"
        aria-pressed={props.isPressed}
        onClick={() => props.setFilter(props.name)}
      >
        <span className="visually-hidden">Show </span>
        <span>{props.name}</span>
        <span className="visually-hidden"> Tasks</span>
      </button>
    );
  }

export default FilterButton;

uj5u.com熱心網友回復：

我們有 3 個布爾欄位：checked, completed, completedAssoc.

  {
    id: "todo-0",
    name: "Brush Teeth",
    checked: false,
    completed: false,
    completedAssoc: false
  },

過濾器將按如下方式作業：

  const FILTER_MAP = {
    All: (task) => !task.completed,
    Associate: (task) => task.checked && !task.completedAssoc
  };

最后改變completeTaskand addTask：

  function completeTask(id) {
    const complField = filter === "All" ? "completed" : "completedAssoc";
    const updatedTasks = tasks.map((task) =>
      id === task.id ? { ...task, [complField]: true } : task
    );
    setTasks(updatedTasks);
  }

  function addTask(name) {
    const newTask = {
      id: "todo-"   nanoid(),
      name: name,
      checked: false,
      completed: false,
      completedAssoc: false
    };
    setTasks([...tasks, newTask]);
  }

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