Unmounting a Component with a SetInterval in React

I’m trying to unmount a component with a setInterval.

This is based on the answer here:

Component:

class ImageSlider extends React.Component {
  constructor(props) {
    super(props);
    this.state = { activeMediaIndex: 0 };
  }

  componentDidMount() {
    setInterval(this.changeActiveMedia.bind(this), 5000);
  }

  changeActiveMedia() {
    const mediaListLength = this.props.mediaList.length;
    let nextMediaIndex = this.state.activeMediaIndex + 1;

    if(nextMediaIndex >= mediaListLength) {
      nextMediaIndex = 0;
    }

    this.setState({ activeMediaIndex:nextMediaIndex });
  }

  renderSlideshow(){
    const singlePhoto = this.props.mediaList[this.state.activeMediaIndex];
      return(
        <div>
          <img src={singlePhoto.url} />
        </div>
      );
    }

  render(){   
    return(
      <div>
          {this.renderSlideshow()}
      </div>
    )
  }
}

Right now, when I go to another page, I get this error:
Can only update a mounted or mounting component. This usually means you called setState() on an unmounted component

So I added something like this:
   componentWillUnmount(){
    clearInterval(this.interval);
  }

I’ve also tried:
   componentWillUnmount(){
    clearInterval(this.changeActiveMedia);
  }

But I’m still getting the above error every 5 seconds. Is there a proper way to clear the interval?

Answers:

Thank you for visiting the Q&A section on Magenaut. Please note that all the answers may not help you solve the issue immediately. So please treat them as advisements. If you found the post helpful (or not), leave a comment & I’ll get back to you as soon as possible.

Method 1

setInterval returns an in interval Id that you can use in clearInterval.

More info on setInterval

Something like this should work:

this.myInterval = setInterval(this.changeActiveMedia.bind(this), 5000)

then in componentWillUnmount:

clearInterval(this.myInterval);


All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

0 0 votes
Article Rating
Subscribe
Notify of
guest

0 Comments
Inline Feedbacks
View all comments
0
Would love your thoughts, please comment.x
()
x