How to get values from child components in React

Question

So I am just starting to use React and am having trouble gathering the input values of inputs within a child component. Basically, I am creating different components for a large form I am making, then in the encompassing component, I want to collect all the values of inputs on the children in an object I am calling data, and then send that collected input into a POST AJAX request (you can see an example in the last component I made). I can pull the values easily enough when I am inside of the components, but pulling them from the parent component I haven't figured out.

Thanks in advance. Just going through the pains right now with React so any recommendations on how to structure this better as well, I am all ears!

Here are my components:

Component one

var StepOne = React.createClass({
  getInitialState: function() {
    return {title: '', address: '', location: ''};
  },
  titleChange: function(e) {
    this.setState({title: e.target.value});
  },
  addressChange: function(e) {
   this.setState({address: e.target.value});
  },
  locationChange: function(e) {
    this.setState({location: e.target.value});
  },
  render: function() {
    return (
      <div className="stepOne">
        <ul>
          <li>
            <label>Title</label>
            <input type="text" value={this.state.title} onChange={this.titleChange} />
          </li>
          <li>
            <label>Address</label>
            <input type="text" value={this.state.address} onChange={this.addressChange} />
          </li>
          <li>
            <label>Location</label>
            <input id="location" type="text" value={this.state.location} onChange={this.locationChange} />
          </li>
        </ul>
      </div>
    );
  }, // render
}); // end of component

Component two

var StepTwo = React.createClass({
  getInitialState: function() {
    return {name: '', quantity: '', price: ''}
  },
  nameChange: function(e) {
    this.setState({name: e.target.value});
  },
  quantityChange: function(e) {
    this.setState({quantity: e.target.value});
  },
  priceChange: function(e) {
    this.setState({price: e.target.value});
  },
  render: function() {
    return (
      <div>
      <div className="name-section">
        <div className="add">
          <ul>
            <li>
              <label>Ticket Name</label>
              <input id="name" type="text" value={this.state.ticket_name} onChange={this.nameChange} />
            </li>
            <li>
              <label>Quantity Available</label>
              <input id="quantity" type="number" value={this.state.quantity} onChange={this.quantityChange} />
            </li>
            <li>
              <label>Price</label>
              <input id="price" type="number" value={this.state.price} onChange={this.priceChange} />
            </li>
          </ul>
        </div>
      </div>
      </div>
    );
  }
});

Final component to collect data and submit ajax request

EventCreation = React.createClass({
 getInitialState: function(){
  return {}
},
submit: function (e){
  var self

  e.preventDefault()
  self = this

  var data = {
    // I want to be able to collect the values into this object then send it in the ajax request. I thought this sort of thing would work below:
    title: this.state.title,
  }

  // Submit form via jQuery/AJAX
  $.ajax({
    type: 'POST',
    url: '/some/url',
    data: data
  })
  .done(function(data) {
    self.clearForm()
  })
  .fail(function(jqXhr) {
    console.log('failed to register');
  });
},
render: function() {
    return(
      <form>
        <StepOne />
        <StepTwo />
        // submit button here
      </form>
    );
  }
});

Answer 1

Define methods in the child components that return the data that you want and then in the parent component when you are rendering the children, define refs so later on when you want to retrieve the data that you need you can call those method on the children.

StepOne = React.createClass({
    getData: function() {
        return this.state;
    }
});

StepTwo = React.createClass({
    getData: function() {
        return this.state;
    }
});

EventCreation = React.createClass({
    submit: function() {
        var data = Object.assign(
            {},
            this._stepOne.getData(),
            this._stepTwo.getData()
        );

        // ... do AJAX
    },

    render: function() {
        return (
            <StepOne ref={(ref) => this._stepOne = ref} />
            <StepTwo ref={(ref) => this._stepTwo = ref} />
        );
    }
});