TestView.js

define(['react'], (React) => {
  class TestView extends React.Component {

    constructor(props) {
      super(props);
      this.state = {
        value: 10
      };
    }

    handleChange() {
      console.log(this);
      this.setState({value: event.target.value});
    }

    render() {
      var value = this.state.value;
      return(
        <div className="testView">
        <input type="text" defaultValue={value} onChange={this.handleChange.bind(this)} />
        {value}
        </div>
      );
    }
  }
  return TestView;
});