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JavaScript React Basics (2018) Understanding State Understanding State Review

Garrett Hughes
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Garrett Hughes
Python Development Techdegree Student 32,971 Points
Posted by Garrett Hughes
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Garrett Hughes
Python Development Techdegree Student 32,971 Points

I can't figure out what's suppose to go here. I've reviewed the videos a few times. I guess I'm just missing it.

Complete the code so that the isConfirmed state updates its value based on the previous state.

confirmGuest = () => {
  this.setState( prevState => ({ 
    isConfirmed: !___.isConfirmed
  }));
}

2 Answers

Garrett Hughes
seal-mask
.a{fill-rule:evenodd;}techdegree
Garrett Hughes
Python Development Techdegree Student 32,971 Points
Garrett Hughes
.a{fill-rule:evenodd;}techdegree
Garrett Hughes
Python Development Techdegree Student 32,971 Points

Oh, because it's just changing a boolean value to its opposite. I was thinking it wasnted a '!== prevState.isConfirmed" or something like that and it wasn't clicking lol Dumb question.

Gabbie Metheny
Gabbie Metheny
33,778 Points
Gabbie Metheny
Gabbie Metheny
33,778 Points

! is the logical NOT operator. In this case, it's basically just a quick way of flipping the boolean value. If the isConfirmed state was true, firing this event handler would change it to false; and if it started as false, the handler would flip it to true. Similar to using if/else if logic, but without explicitly writing it all out, since you just want the boolean to flip to the only other option.