How to update parent's state in React?

Question

My structure looks as follows:

Component 1  

 - |- Component 2


 - - |- Component 4


 - - -  |- Component 5  

Component 3

Component 3 s

Answer 1

I've used a top rated answer from this page many times, but while learning React, i've found a better way to do that, without binding and without inline function inside props.

Just look here:

class Parent extends React.Component {

  constructor() {
    super();
    this.state={
      someVar: value
    }
  }

  handleChange=(someValue)=>{
    this.setState({someVar: someValue})
  }

  render() {
    return 
  }

}

export const Child = ({handler}) => {
  return 
}

The key is in an arrow function:

handleChange=(someValue)=>{
  this.setState({someVar: someValue})
}

You can read more here. Hope this will be useful for somebody =)