react.js: removing a component

Well, it seems you should rethink how the display control is handled. React is all about isolated components, and so, you shouldn’t be unmounting a component that is mounted by a parent component. Instead, you should use a callback passed down through props to accomplish something like that.

Your actual implementation will depend on your use case, but an updated version of your example that works is at: https://jsfiddle.net/nt99zzmp/1/

var App = React.createClass({
  render: function() {
    var img = this.state.showImage ? <MyImage /> : '';
    return (
    <div>{img}<RemoveImageButton clickHandler={this.removeImage} /></div>
    );
  },
  
  getInitialState: function() {
      return {
          showImage: true
      };
  },
  
  removeImage: function() {
      this.setState({ showImage: false });
  }
});

var MyImage = React.createClass({
  render: function() {
    return (
      <img id="kitten" src={'http://placekitten.com/g/200/300'} />
    );
  }
});

var RemoveImageButton = React.createClass ({
  render: function() {
    return (
      <button onClick={this.props.clickHandler}>remove image</button>
    )
  }
});

React.render(<App />, document.body);