Passing properties through components in ReactJS, ES6 example

Question

I'm new to React and need some help. I'm trying to rewrite this Facebook's offical example into something own in ES6:

http://codepen.io/gaearon/pen/rrJNJY?editors=0010#0

My code looks like this:

class Person extends Component {
    constructor(props) {
        super(props);
    }
    render() {
        return (
            <div>
                <h3>{this.props.user.name}</h3>
                <h4>{this.props.user.surname}</h4>
                <h4>{this.props.user.age}</h4>
            </div>
        )
    }
}

class VisualAppearance extends Component {
    render() {
        return(
          <div>
              <p>{this.props.user.visuals.eyes}</p>
              <p>{this.props.user.visuals.height}</p>
              <p>{this.props.user.visuals.hair}</p>
          </div>
        );
    }
}

class CreatePerson extends Component {
    render() {
        return(
            <div>
                <h1>Personal Info: </h1>
                <Person user={this.props.user}/>
                <h1>Visual Appearance: </h1>
                <VisualAppearance user={this.props.user}/>
                <h1>Time Created:</h1>
                <p>{this.props.dateCreated}</p>
            </div>
        );
    }
}

var use = {
    user: {
        name: 'Dude',
        surname: 'Dude Surname',
        age: 30,
        visuals: {
            eyes: 'blue',
            height: 180,
            hair: 'dark'
        }
    },
    dateCreated: new Date()
}

ReactDOM.render(
    <CreatePerson name={use.user.name}
    surname={use.user.surname} age={use.user.age} eyes={use.user.visuals.eyes} height={use.user.visuals.height}
                  hair={use.user.visuals.height} date={use.user.dateCreated}
    />
    , document.getElementById('project'));

I get the following error: Cannot read property 'name' of undefined

If I change this just to this.props.user it goes through but the same error as above is reported on the surname.

In the link provided there is: props.user.avatarUrl , so it's a nested structure of the object.

How can I make this work and nesting object's properties like this.props.sth.sthElse.sthElse1 on ES6 Classes in React?

Answer 1

CreatePerson expects a property called user here:

class CreatePerson extends Component {
    render() {
        return(
            <div>
                <h1>Personal Info: </h1>
                <Person user={this.props.user}/>            // <====
                <h1>Visual Appearance: </h1>
                <VisualAppearance user={this.props.user}/>  // <====
                <h1>Time Created:</h1>
                <p>{this.props.dateCreated}</p>
            </div>
        );
    }
}

You're not passing it one. You're passing it name, surname, and a bunch of others, but not user.

It works if you remove all those individual properties and pass it user instead:

ReactDOM.render(
    <CreatePerson user={use.user} />
    , document.getElementById('project'));

Example:

class Person extends React.Component {
    constructor(props) {
        super(props);
    }
    render() {
        return (
            <div>
                <h3>{this.props.user.name}</h3>
                <h4>{this.props.user.surname}</h4>
                <h4>{this.props.user.age}</h4>
            </div>
        )
    }
}

class VisualAppearance extends React.Component {
    render() {
        return(
          <div>
              <p>{this.props.user.visuals.eyes}</p>
              <p>{this.props.user.visuals.height}</p>
              <p>{this.props.user.visuals.hair}</p>
          </div>
        );
    }
}

class CreatePerson extends React.Component {
    render() {
        return(
            <div>
                <h1>Personal Info: </h1>
                <Person user={this.props.user}/>
                <h1>Visual Appearance: </h1>
                <VisualAppearance user={this.props.user}/>
                <h1>Time Created:</h1>
                <p>{this.props.dateCreated}</p>
            </div>
        );
    }
}

var use = {
    user: {
        name: 'Dude',
        surname: 'Dude Surname',
        age: 30,
        visuals: {
            eyes: 'blue',
            height: 180,
            hair: 'dark'
        }
    },
    dateCreated: new Date()
}

ReactDOM.render(
    <CreatePerson user={use.user} />
    , document.getElementById('project'));

<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id="project"></div>