Advanced React

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Reference Values

Use a ref to store a reference to a value, namely the setInterval id.

Using this ref, make it possible to start and stop the timer. To start the timer, you want to count up in seconds (using state). To stop the timer, you will need to clear the timer using clearInterval and the id stored in...

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In this app, we want to make a very basic stopwatch, we want to count up in seconds when we click on start.

And we also want to be able to stop this timer. The trick to implementing this is realizing that we have a set interval function set interval takes a callback, this enables us to count up, t...