Develop Reference

Focus switching to next row in nested recyclerview in FireTv App

In our fire tv app, we are using a nested recyclerview where every vertical item have a horizontal row as a child item like playstore design.
Scrolling with dpad working fine normally but when i hold the right key for few seconds, item start scrolling very fast because it gets many events & within few second focus goes to the next random row even current row has items to scroll. So this whole problem happening in horizontal scroll(child recyclerview). I have already tried many solutions like this, this, this.
Also tried the custom layout manager, custom focus layout & other approach like slowing down the recyclerview scroll etc approach but all not working.

As far as I know, this happens at the moment when the last item is in focus, and the next item is not visible, that is, the ViewHolder has not updated the data of the first cell, so it is not clear which element to show next as if the list has ended.
You need to make sure that at least the edge of the next element is always visible on the screen.
Maybe you should play with the cell size or divider.
Edit:
The secret is to use the leanback library. It isn't lost focus!
Your gradle:
// Leanback support
def leanback_version = "1.2.0-alpha01"
implementation("androidx.leanback:leanback:$leanback_version")
Change in the layout from RecyclerView to HorizontalGridView (VerticalGridView)
Change in the Fragment import from RecyclerView.widget.GridLayoutManager to androidx.leanback.widget.GridLayoutManager
It works very fast for me and the focus no longer jumps.
Here a good article with animations but little outdated

Why RecyclerView items disappear immediately when using Transition API?

This is a question regarding the use of Android Transition API.
I am trying to animate the height change of a list, just like a dropdown menu.
I tried 2 approaches
Use a RecyclerView and animates its height change
Use a ScrollView > LinearLayout hierarchy and animates ScrollView's height.
The 2nd approach works perfectly.
But the 1st approach has a serious glitch - when the collapse transition starts, items disappear immediately.
By looking at the below GIF you can observe clearly the difference:
To be exact, items' visibility changes at the moment I change RecyclerView's LayoutParams, without waiting for the transition to finish, whatever it is expanding or collapsing
Code
I have created a minimal project on Github.
If you just want to look at the code, here is the MainActivity.
Question
Is it possible to achieve ScrollView's effect with a RecyclerView?
If yes, how?

My Idea is to do the transition of all the recycler view rows individual rather than the whole RecyclerView:
So when collapsing iterate through each ROW of a RecyclerView and do a transition. Remember to check for null if some rows are recycled they may return null. So after that collapse the whole recyclerView.
And like wise for the expanding do the same for the views.
This issue is cause by RecyclerView has many views with it but Scroll View has only one View nested in it.

Be able to scroll RecyclerView behind Keyboard

I want to be able to scroll a RecyclerView behind a keyboard. The issue is that if I have say more than 5 items in the RecyclerView.Adapter, and assume that each item might have a height of say 100dp. I want to be able to scroll the RecyclerView down with the keyboard still up and be able to scroll down to be able to see the first item in the RecyclerView.
In iOS you can set something called a contentInset on a NSTableView and that gives you extra scrolling space below the list. I am looking for something similar for the RecyclerView so far, there isn't much to go on.
INITIAL STARTING POINT
WHAT HAPPENS (Can't scroll down anymore)
WHAT I WANT (be able to scroll down)

ListView - scroll an item so it touches top of view?

Possible? I know there's smoothScrollToPosition() (in api >= 8), but that doesn't make the requested element touch the top of the listview. It just says that the item will be visible.
I imagine I could measure each item somehow and set the scroll position manually, this doesn't help on my last few rows though, since those should not be allowed to scroll to the top anyway.
Use case - I want me users to pop open the keyboard and comment on an item in my ListView. The ime keyboard will cover some portion of the screen, so I want the 'focused' row to be touching the top of the view so they remember what they're commenting on.
Thanks

I think you can add a big & empty footerView when your user open the keyboard.
and remove the footerview when user close the keyboard.
if you add a big footerview, you can use ListView.SetSelection(last_row_pos)
After that, the last row will touch top of view.

I think you can use a set of flags in your manifest under your activity element which will allow you to do this. Please check the docs to see what your various options are.

Android listview (array adapter) custom scrolling

I would like to change the default behaviour of my listview, so when im scrolling to the last item, the list will keep scrolling untill the last item is at the top of the list.
default behaviour stops scrolling when the last item is fully in view.
Any ideas on how i can go about this pre 2.3?
Thanks,
Totem.

In case anyone is interested in the solutions available it either:
1) add to the list view padding, that solution forces you to play around with the fading edge property since it gets sifted because of thee padding. also this method might not work well if your using a transparent background because items will be rendered and visible under the padding area. Although this could be fixed by entering the list into a relative layout and making sure to draw something over that area.
2) add transparent items to the listview for offset and not set them as enabled to avoid dividers, just need to make sure to change getItemCount and getItemTypeCount and so on if your if your item isn't really inside your adapter as per my case.
I went with option two.
Thanks,
Totem.