这是索引文件,它是任务卡片的容器。
import TaskCard from './TaskCard'
export function Task() {
const tasks = useSelector((state) => state.tasks);
const dispatch = useDispatch();
const [task,setTask] = useState("");
const [time,setTime] = useState("");
function submitTask() {
let newTask = {
id: Math.floor(Math.random() * 10000),
content: task,
time: time,
remainingTime: time,
isRunning: false,
};
dispatch(create(newTask));
}
return (
<div>
<input type="text" onChange={(e) => setTask(e.target.value)}/>
<input type="number" onChange={(e) => setTime(e.target.value)}/>
<input type="button" value="submit task" onClick={submitTask} />
{tasks.map((i) => TaskCard(i))}
</div>
);
}
这是 TaskCard.js 文件。
import useTimer from '../../hooks/useTimer' // custom hook which decreases `time` per second using setInterval API
export default function TaskCard(task) {
const delay = 1000;
const dispatch = useDispatch();
useTimer(
() => {
if (task.remainingTime > 0) {
dispatch(tick(task.id));
}else if (task.remainingTime === 0) {
dispatch(toggleIsRunning(task.id))
}
},
task.isRunning ? delay : null
);
return (
<div key={task.id} style={{ padding: "10px", width: "200px", margin: "20px auto", border: "orange solid 1px", borderRadius: "5px" }}>
<p>{task.content}</p>
<p>{task.remainingTime}</p>
<button onClick={() => dispatch(remove(task.id))}>remove</button>
<button onClick={() => dispatch(toggleIsRunning(task.id))}>play/pause</button>
<button onClick={() => dispatch(reset(task.id))}>reset</button>
</div>
);
}
代码最初呈现良好。但是在添加新任务时,我得到了这个错误
Warning: React has detected a change in the order of Hooks called by Task. This will lead to bugs and errors if not fixed. For more information, read the Rules of Hooks: https://reactjs.org/link/rules-of-hooks
Previous render Next render
------------------------------------------------------
1. useContext useContext
2. useReducer useReducer
3. useMemo useMemo
4. useRef useRef
5. useRef useRef
6. useRef useRef
7. useRef useRef
8. useLayoutEffect useLayoutEffect
9. useLayoutEffect useLayoutEffect
10. useDebugValue useDebugValue
11. useContext useContext
12. useState useState
13. useState useState
14. undefined useContext
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
at Task (http://localhost:3000/static/js/main.chunk.js:492:80)
at div
at App
at Provider (http://localhost:3000/static/js/0.chunk.js:36550:20)
console.<computed> @ index.js:1
overrideMethod @ react_devtools_backend.js:2430
printWarning @ react-dom.development.js:67
error @ react-dom.development.js:43
react-dom.development.js:15162 Uncaught Error: Rendered more hooks than during the previous render.
at updateWorkInProgressHook (react-dom.development.js:15162)
at updateRef (react-dom.development.js:15694)
at Object.useRef (react-dom.development.js:16433)
at useRef (react.development.js:1516)
at useTimer (useTimer.js:4)
at TaskCard (TaskCard.js:9)
at index.js:29
at Array.map (<anonymous>)
at Task (index.js:29)
我该如何解决这个问题?我应该重组我的代码吗?如果我需要添加更多细节以提高清晰度,请告诉我。提前致谢。
最佳答案
{tasks.map((i) => TaskCard(i))}
因为您直接在 Task
中调用函数 TaskCard
,所以 TaskCard
中的 useDispatch()
Hook 实际上被视为 Task
中的 Hook 调用。您必须指定 TaskCard
是组件而不是普通函数,以便 React 正确地将 useDispatch()
视为函数组件 TaskCard 中的 Hook 调用
:
{tasks.map((props) => <TaskCard {...props} />)}
关于javascript - 在 React 中呈现比以前呈现错误更多的钩子(Hook),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/65834138/