Using setState

- [Instructor] We know how to add state variables…to our React applications, but how do we change state?…Well, we're going to use a function called setState,…which is going to change the state variable…within our component.…So let's go ahead and add a method here…that will trigger that change in state.…And it's going to be called toggleOpenClosed.…So toggleOpenClosed is going to…have this function called setState.…SetState is going to take in an object,…which resets the state.…

So it'll have a key called open,…matching our state variable,…and then we'll do whatever the opposite of that is.…So in this case, it's false.…We'll say open.…setState will change it to the opposite, so true.…All right.…The next thing I need to do here is…whenever we're using a constructor method,…we need to bind this.…So, in other words, I need to say this.toggleOpenClosed,…and we'll set this equal to this.toggleOpenClosed.bind this.…

What this'll do is it'll make this accessible…within the context of this custom method.…So now that I've done this,…