RecyclerView with DiffUtil - MVVM News App

[@Traffic_Pro]

Hey Philipp brother you helped me a lot by showing how to use DiffUtil. Thank you so much🙌

[@matt-g-recovers]

I Gotta say I love this part, such a good optimization.

[@BaljeetSingh-ib1pf]

Hey Philipp, Thanks for this amazing lesson over diffUtil. Could you explain how to assign items list to this adapter. Thanks

[@bharathpediredla549]

You explained it better man. 👌🏼

[@PhilippLackner]

better than what? :D

[@bharathpediredla549]

@@PhilippLackner Than the stupid Documentation 😂😂.

[@PhilippLackner]

@@bharathpediredla549 thanks 😂👍

[@mhmitsray]

hey :) just a few questions (all towards the end of the video): 1. Wouldn't it be better to make the setOnItemClickListener function private? or is it for external use? 2. I'm getting an error when add '.name' to: tvSource.text = article.source.name

[@rodneyperello]

Everything is in good programming style.

[@tiagosutter8821]

First of all, thanks for the course. I have a question related to big android projects in general What are the advantage of having all the 'adapters' in one top level package in big projects? I see this often, the same for ViewModels. When we get to a point of having 50+ adapters (my case) it gets kind of messy, and most adapters are used in one single place in my application. The same happens to viewmodels folder. For example in an app we have some screen related to payment, to get better separation i put everything related to payment screens in the ui.payment package Then i have packages like ui.payment.viewmodels, ui.payment.fragments, ui.payment.adapters, etc The adapters related to payment are used only for the screens related to payment, so i see no reason to put them in a top level 'adapters' package, same thing with the ViewModels. Is there some big disadvantage of working with this structure that I described that i'm just not seeing? Thanks again for the awesome content.

[@PhilippLackner]

You're totally right with that, this is not the structure I would use for big scale apps. I think for this simple app and tutorial here it's not a big issue though :)

[@felipepereira3061]

I still got confused about the line 58, with the : ((Article) -> Unit)? it is an Article object?Why all the Unit? declarations?

[@ubersticks]

"Unit" in Kotlin is just like "void" in Java -- "-> Unit" means this function that accepts "Article" as a parameter does not return anything.

[@egementt245]

@@ubersticks Great explanation! Thanks a lot.

[@yootewb]

It is not an Article object. It is actually a nullable function that takes an Article as an argument and returns Unit (the equivalent of void in Java). We are simply assigning a variable to represent a function that we can choose to either implement or leave null.

[@j2ck1e]

Is the setOnClickListener attribute of item layout?

[@johntotetwoo]

Hello, how do you add a button click listener inside the recyclerview and notify it when that item's property has been changed?

[@brucebane7401]

what does listener mean ???

[@fu7ur3gh057]

Hello Phill,can you show us how to filter recycler view with DiffUtil?for example at SavedNewsFragments?

[@firantemilan]

Thank you very much. How many videos are there in total?

[@PhilippLackner]

In total 12 videos. You're welcome 👍

[@testapp616]

Thank you for everything :)

[@matt-g-recovers]

Perfect! Thanks so much!

[@ackerman6992]

Can anyone explain me about that onitemclicklistener and all? It is bad practice to call setonclicklistener in bind viewholder right? Then why he used it there?

[@himanshujain718]

Please upload video on how to implement seach saved news in saved news fragment.

[@iam-learning6374]

Hi @Philipp Lacker.... may I know what is the difference between ListAdapter and AsyncListDiffer? and which one to use ? Great tutorial as always! thanks.

[@yootewb]

Not much of a difference. ListAdapter is just an extension of RecyclerView.Adapter that uses AsyncListDiffer to calculate the differences on a background thread. If your list is dynamic (like in this video), it would be better to opt for ListAdapter because the constructor requires you to specify a Diff checker and therefore prevent you from forgetting to do so.

[@muthami_duncan]

Hi Phil, How can I use view binding here?

[@jayceeddeyro1406]

Do you have a video where you use diffUtil and with databinding?

[@Omsamara6]

When you're setting all of those textviews (tvSource, tvTitle, etc) do they have to be inside of the apply block? None of those reference "this" (the view) so I'm not sure why it's in the apply block. Same applies to the setOnClickListener. Great tutorial as always, thank you

[@PhilippLackner]

They do reference the view (itemView). Otherwise you would have to write holder.itemView.* for every view you reference. Same counts for onclicklistener

[@albertocastro5496]

How would you set up a listener to handle clicks on a view that is inside of a list item, for example if you wanted to execute some code after clicking on your tvTitle view

[@chuka_obi5167]

Hey Phillip this is a really great tutorial! Thank you for sharing. Can you create a tutorial in future that uses data binding and ListAdapter for recyclerview? I currently use ListAdapter for my recyclerview but I can't tell which one is better, using a Recyclerview.Adapter or ListAdapter

[@yootewb]

Not much of a difference. ListAdapter is just an extension of RecyclerView.Adapter that uses AsyncListDiffer to calculate the differences on a background thread. If your list is dynamic (like in this video), it would be better to opt for ListAdapter because the constructor requires you to specify a Diff checker and therefore prevent you from forgetting to do so.

[@sohilupadhyay4804]

Why do you use Diff utils in RecyclerView? You can also create seperate adapter class different Fragments ?

[@joywanjiku2317]

1:18-2:15 DiffUtil is more efficient & runs in the background thread compared to NotifyDataSetChanged

[@shyngyskhann]

AMAZING!

[@ajaygalagali5963]

It would be helpful to beginners, if you explain in more details

[@PhilippLackner]

This is not a beginner tutorial though. Don't skip the basics

[@DriveWithHamza]

Thumbs up Philipp

[@FelixEsUnDios]

I'm here October 2022

[@dennisgonzales9521]

Thanks bro! You're awesome 👌👍

[@PhilippLackner]

You're welcome!

[@chuka_obi5167]

Also, for my ListAdapter, I don't know why it will only work if I write my code like this val itemToRemove = ToDoItem(toDoText, isCompleted) viewModel.removeFromToDoList(itemToRemove) toDoAdapter.submitList(null) toDoAdapter.submitList(viewModel.toDoList.value!!) toDoAdapter.notifyDataSetChanged() Isn't the point of a DiffUtil so that you dont need to call notifyDataSetChanged()

[@osmanmusse9432]

Great video

[@hasanal-qaisi8712]

Thank you for this valuable information. I have a question, what if my adapter receive data of type (any) and i cast the data in the adapter. How can I implement DiffUtil in this case (Of having multiple data types) ?

[@PhilippLackner]

check with a when-expression what type of data you're dealing with

[@hasanal-qaisi8712]

@@PhilippLackner I tried to make differItemCallback of type Any and checked the type of data by using when expression I faced two problems: 1- Suspicious equality check: equals() is not implemented in Object DiffUtilEquals I solved this first problem by making the data class implement an interface that override equals function and make the differItemCallback type of this interface. 2- The second problem is that neither areItemsTheSame() nor areContentsTheSame() working.. I logged them and found out that they're not getting called. I don't know why.

[@PhilippLackner]

@@hasanal-qaisi8712 you can also compare the hashcodes of 2 items to check if the contents are the same

[@SudhanshuKumar-xy6xv]

Now how do I access imageview with view binding as this method is deprecated plz help

[@tjgolder99]

First write --> private lateinit var binding: ItemArticlePreviewBinding inside the class NewsAdapter and then in onBindViewHolder write this ---> val ivArticleImage = binding.ivArticleImage and then use ivArticleImage in into(ivArticleImage) . Hope you understand .. If you feel any difficulty contact me.

[@IlyaTihii]

Phillip, you can help me. How do I change Bindviewholder so that tv.Source, tv.Title and so on are not highlighted in red.

[@i5470]

lateinit var binding: ItemArticlePreviewBinding ... override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ArticleViewHolder { binding = ItemArticlePreviewBinding.inflate(LayoutInflater.from(parent.context), parent, false) return ArticleViewHolder(binding) }

[@akshaykalola]

I have one recyclerview with nestedscrollview. That's works perfectly as normal. But, when I tried to improve it with diffutil it don't appear. So, what is the issue I don't know?? Please, help me.

[@amineayachi335]

Thanks

[@amateur_gamer101]

when setting up the glide, i cant find the ".urlToImage" to call. what's the problem?

[@9769ug]

the NewsAPi no longer has a field for urlToImage, does anyone know a workaround to get the images?

[@praystation0409]

I am here January 2022

[@mex5341]

it's better to implement ListAdapter to Adapter Class

[@tabrezlj7057]

Why do you have the setOnItemClickListener function when you didn’t even call it ?

[@ackerman6992]

Did you got any answer?

[@brucebane7401]

isnt onitemclicklistener a keyword how can we name a variable like that ????

[@mubaraknative]

phillip get 123K subscriber's at 02/08/2023 at 11:09 AM

[@yasminedwedar8651]

A failure occurred while executing org.jetbrains.kotlin.gradle.internal.KaptExecution i got this error helpppp

[@mikec4220]

Hi Yasmine, had the same issue... In Article class replace "val author : Any" with "val author : String" .. it worked on my end but I don't know if I messed it up in the long run.. although it should not be a big issue.

[@nirajmalpani9589]

@@mikec4220 Thanks buddy... I had the same error it worked👍

[@roopkishore785]

This tutorial series is not for beginners, I am beginner and I am totally confused.

[@pembatamang8233]

who the heck hit dislike. Must be high haha

[@aakashroushann1602]

tried your way but unfortunately the list disappers after using diffutil...hope you can help here's the link to my adapter class: pastebin.com/v4jshBgZ

[@Sk-gb2hx]

+

[@innocentkumwenda8139]

sir I cant get my view in my layout file in the overrided function "onBindViewHolder" this part : holder.itemView.apply { }

[@vikramshah-01]

hey !! did you able get the solution ?