How to set Parent State from Children Component in ReactJS?

Last Updated : 27 Jan, 2021

We can set Parent State from Children Component in ReactJs using the following approach.

Prerequisite: State introduction in ReactJS

We will actually set the state of a parent in the parent component itself, but the children will be responsible for setting.
We will create a function in parent to set the state with the given input.
We will pass that function in children as a prop.
Then Children will call the function with a new Value.
We will set the state of the parent in the function.

Creating React Application:

Step 1: Create a React application using the following command:

npx create-react-app foldername

Step 2: After creating your project folder, i.e., folder name, move to it using the following command:

cd foldername

Project Structure: It will look like the following.

Project Structure

Step 3: Now create Parent and Children components in the src folder with the following code.

Filename- Child.js:

Javascript

import React,{ Component }  from 'react'; 
   
class Child extends Component { 
  
  constructor(props) { 
    super(props); 
    this.handleClick.bind(this); 
  } 
    
  handleClick = () => { 
    // We will start the process of changing 
    // state of parent from Here... 
  } 
  
  render() { 
    return ( 
        <button onClick={this.handleClick}>Reveal Title</button> 
    ); 
  } 
} 
  
export default Child;

Filename- Parent.js:

Javascript

import React,{ Component }  from 'react'; 
import "./parent_css.css"
  
// Importing child component for rendering 
import Child from './child'; 
   
class Parent extends Component { 
  
  constructor(props) { 
    super(props); 
    this.state = {title: ""}; 
  } 
  
  render() { 
    return ( 
        <React.Fragment> 
          // Rendering title of state initially empty. 
          <h1> {this.state.title} </h1> 
            
          // Rendering child component here which  
          // contains only a button 
          <Child /> 
        </React.Fragment> 
    ); 
  } 
} 
  
export default Parent;

Step 4: Create function setStateOfParent to set state of Parent in Parent component, also pass setStateOfParent function in children.

Filename- Parent.js:

Javascript

import React,{ Component }  from 'react'; 
import "./parent_css.css"
  
import Child from './child'; 
   
class Parent extends Component { 
  
  constructor(props) { 
    super(props); 
    this.setStateOfParent.bind(this); 
    this.state = {title: ""}; 
  } 
  
  // Creating below function to set state  
  // of this (parent) component. 
  setStateOfParent = (newTitle) => { 
    this.setState({title: newTitle}); 
  } 
  
  render() { 
    return ( 
        <React.Fragment> 
          <h1> {this.state.title} </h1> 
            
          // Passing the setStateOfParent function  
          // in child as a prop 
          <Child setStateOfParent = {this.setStateOfParent}/> 
        </React.Fragment> 
    ); 
  } 
} 
  
export default Parent;

Step 5: Now access and call the setStateOfParent function in children whenever you want to set the state of the parent.

Filename- Child.js:

Javascript

import React,{ Component }  from 'react'; 
   
class Child extends Component { 
  
  constructor(props) { 
    super(props); 
    this.handleClick.bind(this); 
  } 
  
  handleClick = () => { 
    // Simply call the setStateOfParent function from  
    // prop and pass required argument 
    this.props.setStateOfParent("Geeks For Geeks"); 
  } 
  
  render() { 
    return ( 
        <button onClick={this.handleClick}>Reveal Title</button> 
    ); 
  } 
} 
  
export default Child;