Passing a Redux Action to a child component with props

Question

I am trying to set a video in my app as "Featured" when a user clicks on an item. I have an action creator that does a simple console.log() when called, and for testing I call it w/ componentDidMount(), and it works fine. I have a separate component for the VideoItem, and I'm trying to pass down the action creator, but I get an error: TypeError: Cannot read property 'props' of undefined. I tried to add .bind(this) to the end of the action I was passing down, but it didn't make a difference.

If the action creator works when I call it at componentDidMount, why can't I pass it to the child component? Here's my Video and VideoItem component:

// Video.js


import React, { Component } from 'react'
import VideoItem from './VideoItem'
class Videos extends Component {
  componentDidMount() {
      this.props.actions.getVideos()
      // This function works, but getting error
      // when passing to VideoItem component
      this.props.actions.setFeaturedVideo()
  }
  constructor(props) {
      super(props);
  }
  render() {
    if(this.props.videos.length == 0){
      return <p>Loading....</p>
    }
    return (
        <div className="container">
          <ul className="row">
              {this.props.videos.map(function(result) {
                return (
                    <VideoItem
                    key={result.position}
                    setFeaturedVideo={this.props.setFeaturedVideo}
                    video={result}

                    />
                )
              })}
          </ul>
        </div>
    )
  }
}

export default Videos


// VideoItem.js

import React, { Component } from 'react'
class VideoItem extends Component {
  constructor(props) {
      super(props);
  }
  render() {
    return (
      <li className="col m6" onClick={this.props.setFeaturedVideo()}>
          {this.props.video.title}
      </li>

    )
  }
}
export default VideoItem

Answer 1

Missed that this inside a map function. Since you are using map, the "this" belongs to the map function. You need to assign this to a variable before the map function and use that instead.

render() {
    var _that = this;
    if(this.props.videos.length == 0){
      return <p>Loading....</p>
    }
return (
    <div className="container">
      <ul className="row">
          {this.props.videos.map(function(result) {
            return (
                <VideoIte
                key={result.position}
                setFeaturedVideo={_that.props.actions.setFeaturedVideo}
                video={result}

                />
            )
          })}
      </ul>
    </div>
)

}