I have a parent component which is like this:

import "./styles.css";
import ChildComponent from "./childComponent";
import { useState, useEffect } from "react";

const persons = [
  {
    id: 1,
    name: "foo",
    age: 20,
  },
];
export default function App() {
  const [data, setdata] = useState(persons);
  const updateAge = function (idx, newAge) {
    const newData = [...data];
    for (let d of newData) {
      if (d.id === idx) {
        d.age = newAge;
      }
    }
    console.log(newData);
    setdata(newData);
  };
  return (
    <div className="App">
      {data.map((d) => (
        <ChildComponent
          id={d.id}
          name={d.name}
          age={d.age}
          updateAge={updateAge}
        />
      ))}
    </div>
  );
}

The child component looks like this:

import "./styles.css";
import { useState, useEffect } from "react";
export default function ChildComponent({ id, name, age, updateAge }) {
  const [enableSave, setEnableSave] = useState(false);
  const [showAgeInput, setShowAgeInput] = useState(false);
  const [newAge, setNewAge] = useState(age);
  const handleAgeClick = () => {
    setShowAgeInput(true);
  };

  const handleAgeUpdate = () => {
    updateAge(id, newAge);
  };

  const handleSaveEnable = () => {
    setEnableSave(true);
  };
  return (
    <>
      <span>{name} </span>
      <span
        onClick={handleAgeClick}
        style={{ display: showAgeInput ? "none" : "" }}
      >
        {" "}
        {age}
      </span>
      <input
        type="text"
        onChange={(e) => setNewAge(e.target.value)}
        style={{ display: showAgeInput ? "" : "none" }}
        onBlur={handleSaveEnable}
      />
      <button disabled={!enableSave} onClick={handleAgeUpdate}>
        Save
      </button>
    </>
  );
}

Now when I save button after clicking on Age span and updating its value, the re-rendering doesn’t happen due to which I don’t see the input gets hidden and button getting disabled.

I can see updateAge function is called though which in turn should trigger setData and hence re-rendering? But the re-rendering doesn’t seem to happen.

What could be the reason?