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JavaScript React Components (2018) Managing State and Data Flow Update State Based on a Player's Index

Posted by Ruell Magpayo
Ruell Magpayo
508 Points

accessing "score" directly from state as a member of Player allowed?

in 2:32 in function handleScoreChange(), is it allowed to access and change the score inside the players array this way, how come? score is not an item in the state but a member in the players array, so my confusion is from this part. Is there any additional reading about this?

Peter Mingione
Peter Mingione
10,527 Points
Peter Mingione
Peter Mingione
10,527 Points

I have the same question. How does the setState method in the handleScoreChange method know which score to change in the player's array?

handleScoreChange = (index, delta) => {
    this.setState( prevState => ({
      score: prevState.players[index].score += delta
    }));
    // console.log('index: ' + index, 'delta: ' + delta);
  } = (index, delta) => {
    this.setState( prevState => ({
      score: prevState.players[index].score += delta
    }));
    // console.log('index: ' + index, 'delta: ' + delta);
  }