@KaranChecker

I to be honest didnt catch the usage entirely. The concept of the various keys .. yes, but not the usage. 

A slower more hands-on tutorial video would surely help.

@EmanueleTozzato

Of all the videos in the series, I feel like I've started with the most complicated! :)

@nosmirck

I'm not sure if I'm 100% correct, but another useful use of keys (that I've encountered) is finding specific Widgets during Widget Tests and UI Tests. Let's say you're loading the current temperature, you want to know if it rendered, you don't care about the actual reading but that the actual widget holding the value is rendered. In this case, Keys are very useful (unless I'm doing it wrong and there's another way to identify Widgets during Widgets and Integration Tests)

@lucasyoung9594

Angela just sent me here through her flutter bootcamp course. And seriously the Flutter team ROCKS!! Very clear, fun and helpful! Thanks Flutter Team and Emily for this video!

@sanketsahasrabudhe8106

Emily Fortuna can teach instructors all over the world on how to make a video a thousand times more interesting! Great job Flutter Team! Keep more videos coming❤️

@pradeep422

Now we talking!!!!!! Most advanced and productive video in this series!!!!!!

@jatingoyal6682

This is the best explanation any student could have asked for, literally the best teaching video and analogy for me in my entire life, thanks a lot Emily

@RinaldiMeteoric

I'm really happy about choosing Flutter to develop my app. It has been 3 weeks since I've started learning flutter and videos like this really clarify and take out the struggle of understanding documentations. Thank you very much Flutter team.

@korovka

This doesn't make sense. At 1:29, why would two StatelessColorfulTile() widgets have different colours? Aren't they suppose to be identical?

@sergey_molchanovsky

8:30 we need a code example.
I'm struggling with GlobalKey, getting an error "multiple widget in the tree with the same GlobalKey".

@greatestuff

That was super helpful! I really appreciate the detailed explanation of value, global, object, unique keys. I also appreciate the comment about not using random numbers ..it really shows that they are helping people avoid common stumbling blocks. Thanks Flutter Team! Keep up great work! Love these videos. She makes a comment about the BLOC pattern at the end, I would love to see a dedicated video or series of these types of preplanned and well-polished videos on that pattern.

@saviobatista9619

This is the most needed video ever and just found 3 years later lolz

@TheHermitHacker

I'm just getting into Dart2 and Flutter. I'm just now getting into Mobile app development after 20 years of web development. I have a feeling i'll be watching many of these videos for inspiration and to help me hammer out the critical parts.

@danvilela

Every time i watch this i learn a little bit more. Thanks Emily!

@devonedmonds9223

Documentation for keys was not very clear. Finally some clarity!

@noahderebe

The most clear explanation of Keys currently online!!!!

@Trancecend

I need a practical example that details how the GlobalKeys use case at 8:31 is supposed to be structured.

@YTSliv

Effort appreciated.
A very simple concept but confusingly explained.
X(),X(),... X() * 100
Shuffle them
X(),X(),... X() * 100
Renderer see no change, there is no effect because things are not ordered shuffle have no meaning.
The key prop makes
X-1(), X-2(), ... X-100(), 
shuffle,
X-57(),X-2(),...X-3()
now some part changed, re-render, note X-2 will be reused in such case since the prop is the same, so a best practice is item.id and each key should be unique.

@OumSaokosal

I spent 8:27 minutes to find PageStorageKey, which is very important.

@subtex

Excellent video. Really appreciate some more in-depth videos like this, while still being short enough to not be an major investment in time to watch it.