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JavaScript

Posted by Riks Fontein
Riks Fontein
7,523 Points

One thing I don't understand, can somebody explain this?

I get the whole onClick method mine is the same: onClick={() => changeScore(index, -1)}

What I don't get about this is the anonymous function we pass to the method, can someone explain this to me?

Michael Hulet
Michael Hulet
47,913 Points

It doesn't look like your question is linked to any particular video/quiz/challenge. Could you please link it so we have some of the context you're referring to?

Riks Fontein
Riks Fontein
7,523 Points

Here is the link to the video, https://teamtreehouse.com/library/update-state-based-on-a-players-index

1 Answer

Jesse Jafa
Jesse Jafa
33 Points
Jesse Jafa
Jesse Jafa
33 Points

In the Player.js file the <Counter /> component is passed the index as prop, so it has access to it. If you resume the video at 1:48, you'll be able that now each player has their own unique index. It's like having an array of players, and using player[1], player[1] etc.

Previously you used

props.changeScore(-1)

which just changed the score without looking for a specific player

By adding the index like this

changeScore(index, -1)}

the function is now looking to change the score of the player who has the index that was passed on. Basically, by passing the index to the changeScore function, now all the +/- buttons correspond to their players.