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JavaScript React Basics (retired) Designing Data Flow Communicating Events

Where does the value of delta come from?

I'm wondering where the value of delta is coming from? Is it propagated from Counter's onClick call to {props.onChange(-1); all the way up to Application's onScoreChange function?

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1 Answer

Richie Black
Richie Black
27,272 Points

Yes you are correct. It comes from the -1 and +1 that are being passed in the Counter component when the buttons are clicked.

<... onClick = {function() {props.onChange(VALUE HERE); }}