父组件的状态设置，然后是子组件的状态设置，有什么信号吗？

import React, { useState } from 'react';
import ChildComponent from './ChildComponent';

function ParentComponent() {
  const [count, setCount] = useState(0);

  return (
    <div>
      <h1>Parent Component</h1>
      <p>Count: {count}</p>
      <ChildComponent count={count} />
      <button onClick={() => setCount(count + 1)}>Increment</button>
    </div>
  );
}

export default ParentComponent;

import React from 'react';

function ChildComponent(props) {
  return (
    <div>
      <h2>Child Component</h2>
      <p>Count received from parent: {props.count}</p>
    </div>
  );
}

export default ChildComponent;

import React, { useState } from 'react';
import ChildComponent from './ChildComponent';

function ParentComponent() {
  const [count, setCount] = useState(0);

  const handleSignal = () => {
    console.log('Signal received from child component');
  };

  return (
    <div>
      <h1>Parent Component</h1>
      <p>Count: {count}</p>
      <ChildComponent count={count} onSignal={handleSignal} />
      <button onClick={() => setCount(count + 1)}>Increment</button>
    </div>
  );
}

export default ParentComponent;

import React from 'react';

function ChildComponent(props) {
  const handleClick = () => {
    props.onSignal();
  };

  return (
    <div>
      <h2>Child Component</h2>
      <p>Count received from parent: {props.count}</p>
      <button onClick={handleClick}>Send Signal</button>
    </div>
  );
}

export default ChildComponent;