Removing element from DOM after set amount of time

Question

I'm trying to figure out the React way to remove an element from the DOM after an event if fired.

I am attempting to flash an alert (copySuccess) when onClick={this.props.handleCopyFact} is fired, and then fade that alert out after 5 seconds. The state of each of these are set within a parent component.

Here is the code for my component:

module.exports = React.createClass({

render: function() {

var copy = null;
if (!this.props.copying && !this.props.editting) {
  copy = (
    <div className="copy-fact-container" onClick={this.props.handleCopyFact}>
      <i className="icon-copy"></i>
      <span>Copy</span>
    </div>
    );

}

var copySuccess = null;
if (this.props.copySuccess) {
  copySuccess = (
    <div className="copy-success">
      <div><i className="icon icon-clipboard"></i></div>
      <p className="heading">Copied to Clipboard</p>
    </div>
    );
}

return (
  <div className="row-body"
    onMouseEnter={this.props.toggleCopyFact}
    onMouseLeave={this.props.toggleCopyFact}>
    <MDEditor editting={this.props.editting}
      content={this.props.content}
      changeContent={this.props.changeContent}/>
  {copy}
  {copySuccess}
  </div>
);
}
});

Answer 1

One way is to create an Expire component which will hide its children after a delay. You can use this in conjunction with a CSSTransitionGroup to do the fade out behavior.

jsbin

Usage:

render: function(){
    return <Expire delay={5000}>This is an alert</Expire>
}

The component:

var Expire = React.createClass({
  getDefaultProps: function() {
    return {delay: 1000};
  },
  getInitialState: function(){
    return {visible: true};
  },
  componentWillReceiveProps: function(nextProps) {
    // reset the timer if children are changed
    if (nextProps.children !== this.props.children) {
      this.setTimer();
      this.setState({visible: true});
    }
  },
  componentDidMount: function() {
      this.setTimer();
  },
  setTimer: function() {
    // clear any existing timer
    this._timer != null ? clearTimeout(this._timer) : null;

    // hide after `delay` milliseconds
    this._timer = setTimeout(function(){
      this.setState({visible: false});
      this._timer = null;
    }.bind(this), this.props.delay);
  },
  componentWillUnmount: function() {
    clearTimeout(this._timer);
  },
  render: function() {
    return this.state.visible 
           ? <div>{this.props.children}</div>
           : <span />;
  }
});