All language subtitles for 012 Understanding useEffect() Dependencies_en

So we learned about U.S. effect, just like with you state, you can have multiple use affect calls

in one in the same component, you can have as many as you want, just as with the U.S. state.

So here I could have another use of effect call and in dysfunction.

Just want to console log rendering ingredients.

I'm not specifying a second argument.

And therefore, this will run for every well, Virender cycle here.

So for now, saved, as you see, it runs twice reason for dad, simply as this component gets rendered

and then dispersed.

Effect also executes and goes ahead, fetches data.

So that's the first render cycle.

And then once the state of searching is done, which happens in the future because it takes a while,

only a few milliseconds, but still then we opted to state and hence we rendered this component again.

And therefore we have a never rendered cycle.

And that's why we see rendering ingredients twice here.

So you can have multiple use effect calls and you can control how they execute with this second argument,

with this array.

Now, you should configure disarray in an honest way, though, so you should really specify your dependencies

if you have a dependency like sub, for example, here.

I'm outputting user ingredients, then you should specify it, you can, of course, omit the second

argument if you know you want to Ronda's for every Virender cycle.

But if you know, you only want to run as if it has changed, you should specify that this case user

ingredients is a dependency of the second effect.

And this means the dysfunction here will now only run when user ingredients changed.

Right now in this app, that's the same as running it on every renderer cycle.

But if we had something else that could be executed, which also renders this, let's say we had some

other value, we're managing in there, which we can change with a set state called in the end, then

dysfunction would only execute of user ingredients changed and not have that abre value changed.

And we'll see that concept of having arguments here throughout this module, because it is very important.

So that's use of fact and how you can configure it or at least the basics about the use effect.

But there is more to use effect than what we see thus far.