CODEWITHSUNDEEP
javascriptreactjsjsx
Giedrius
Giedrius

Reputation: 138

Cannot read property '0' of undefined - stuck with reactjs tutorial

I stuck at the "Storing a history" part of the tutorial, trying to pull state up from Board to Game. I've removed constructor from Board and was trying to change Board so that it takes squares via props:

 renderSquare(i) {
    return <Square value={this.props.squares[i]} onClick={() => this.props.onClick(i)} />;
  }

but it fails..

code: https://codepen.io/gka/pen/eBgapz

Upvotes: 3

Views: 6220

Answers (2)

zabeltech
zabeltech

Reputation: 971

In your example, you pass in squares as props. So you need to change 

renderSquare(i) {
    return (
      <Square 
        value={this.props.squares[i]}
        onClick={() => this.props.onClick(i)}
      />;
    );
}

into 

renderSquare(i) {
    return (
      <Square 
        value={this.props[i]}
        onClick={() => this.props.onClick(i)}
      />;
    );
}

Because this.props already refers to the squares you passed in.

Upvotes: 5

mgPePe
mgPePe

Reputation: 5907

I had my App render Board instead of Game, so that was the reason it wasn't working.

Upvotes: 0

Related Questions