Context
I have a nested Recyclerview like the following sketch shows you:
In the drawing you can see a RecyclerView, which in turn holds one RecyclerView each as item.
Question
My question now is: How can I get the outer, parent Recyclerview scroll to a position of one of the child RecyclerViews. In the drawing I marked you Content pos 5 as my target position for example the Child RecyclerView 2.
What I already found out
One approach I've been thinking about was using scrollToPositionWithOffset(position, offset) on the parent RecyclerView, then just scroll to the position of the child RecyclerView 2 and then have the offset as the size of the list of items in the Child RecyclerView. But how can I get the size when the view isn't even inflated?
I would be very happy if one of you could give me some help that also ran into this problem of scrolling to a position of the child RecyclerView in such a nested Recyclerview.
Related
How can I implement this kind of UI, where we have two recyclerViews. One scrolls horizontally and the second one vertically. when the second one scrolls first one also scrolls top together.
I tried to implement using NestedScrollView, but I had to make second recyclerView height wrap content which causes recyclerView not recycle.
The second way that I tried was having one recyclerView. And adding horizontal recyclerview as a header. The problem was to save header recyclerview scroll state when navigation. And there had been crashes when loading next page (paging 3) in header recyclerView.
The question is: Is there any optimal solution for this kind of ui?
In cases, Like this, you don't have to use 2 RecyclerView and you also have to avoid using RecyclerView insideScrollView. instead of this you have to use one vertical RecyclerView with multitype view Adapter.
in this way, you are going to have 2 different ViewHolder one of them is a horizontal recyclerView (your top item) and the other one is your other items.
for learning multitype adapter you can see this:
How to create RecyclerView with multiple view types
and for a horizontal recyclerView inside a vertical RecyclerView you can see this :
https://medium.com/#ashishkudale/android-list-inside-list-using-recyclerview-73cff2c4ea95
you have to combine these 2.
I could not understand the meaning of "header" where you said "adding horizontal recyclerview as a header" but if you did what I told and the problem is the state of inner Horizontal recyclerView, I think probably you are calling setAdapter method of horizontal RecyclerView in OnBind() method of your vertical recycler view, it is a common mistake that I have seen in many tutorials.
if you have done this mistake , try to call setAdapter of your inner recyclerView in the constructor of its viewHolder and just update the list using yourHorizontalAdapter.notifyDataSetChanged() in onBind() method of VerticalRecylerView,
and if its not the case and your recyclerView is completely destroying see this link :How to save RecyclerView's scroll position using RecyclerView.State?
I'm trying to design a row list using RecyclerView like Android TV ↳ android.support.v17.leanback.widget.ListRow. I'm able to design list with title but not row list. Can anyone help me?
Please Follow this Link for
Recycer view like play store
Use Two RecyclerView Outer Recycler is vertical and Second horizontal recycler is item of first recycler View
All you need is to call mInnerRecycler.setNestedScrollingEnabled(false); on your inner RecyclerViews and use Horizontal scrollview as root of mInnerRecyclerView
Explanation:
RecyclerView has support for nested scrolling introduced in API 21 through implementing the NestedScrollingChild interface. This is a valuable feature when you have a scrolling view inside another one that scrolls in the same direction and you want to scroll the inner View only when focused.
In any case, RecyclerView by default calls RecyclerView.setNestedScrollingEnabled(true); on itself when initializing. Now, back to the problem, since both of your RecyclerViews are within the same ViewPager that has the AppBarBehavior, the CoordinateLayout has to decide which scroll to respond to when you scroll from your inner RecyclerView; when your inner RecyclerView's nested scrolling is enabled, it gets the scrolling focus and the CoordinateLayout will choose to respond to its scrolling over the outer RecyclerView's scrolling. The thing is that, since your inner RecyclerViews don't scroll vertically, there is no vertical scroll change (from the CoordinateLayout's point of view), and if there is no change, the AppBarLayout doesn't change either.
In your case, because your inner RecyclerViews are scrolling in a different direction, you can disable it, thus causing the CoordinateLayout to disregard its scrolling and respond to the outer RecyclerView's scrolling.
Notice:
The xml attribute android:nestedScrollingEnabled="boolean" is not intended for use with the RecyclerView, and an attempt to use android:nestedScrollingEnabled="false" will result in a java.lang.NullPointerException so, at least for now, you will have to do it in code.
RecyclerView can check View Type for return header or item. And use layout manager for manage how to item scrolling direction.
RecyclerView (vertical scrolling)
- item -> RecyclerView (horizontal scrolling) check view type is header or item with condition example : is object has type header
Ref : Google play store like interface using recycler view
Here is my situation: I am using a nested recyclerview. I have a list built with RecyclerView, and I have another horizontal recyclerView as the list item inside.
The inner recyclerView contains some objects. While not all the item have the same height. The height changes according to the content itself.
My problem is: when I scroll the inner RecyclerView, I see its item can't adjust height automatically. Instead sometimes some content is hidden and I can't see the whole of it.
Any way to fix this issue? If my description is not enough, I will provide a buildable project as demostration.
I have a Recyclerview inside another RecyclerView, the inner recyclerview item views are clickable. When I click any item view in the inner recyclerview, it is not scroll to top, I tried using scrollToPosition(position) and scrollTo(X, Y) methods but no luck. I guess I have to scroll the outter recyclerview to achieve it, but don't know how to scroll parent recyclerview from child recyclerview. Can somebody help me on this?
Regards,
Rajapandian.
I want Horizontal scrollable items in vertical recyclerView. horizontal items will not be more than 10 in any case.
I thought of two approaches
1) Horizontal Recyclerview as item in vertical RecyclerView
2) Custom horizontalScrollView as an item in vertical RecyclerView
I have implemented first one facing some issues in scrolling but I think I will manage that.
My question is, why not second approach. I have seen all related question on SO and most of them trying to do with first approach. Why is it so?
What is disadvantage? specially I you have limited number in horizontal view.
Any pointer would be great help.
Why do we use RecyclerView instead of LinearLayout?
Because if we use a LinearLayout consisting of (let's say 50 items) they will be all rendered on screen (50 Views) and this will lead to very very bad performance issues and scalability issues. RecyclerView does initialize the views that appears on screen only ,let's say 7 views, and they will be recycled in every new row that comes.
Why do we use Horizontal Recyclerview instead of Horizontal ScrollView?
This is not usually the case. If you have multiple items in every row that needs to be recycled then you should use Horizontal RecyclerView otherwise it won't matter at all.
To summarize,
The views in the vertical RecyclerView will got recycled whether it has another horizonal RecyclerView or Horizontal ScrollView, but the views inside the Horizontal ScrollView will not get recycled and the views inside the Horizontal RecyclerView will got recycled as it's a RecyclerView.
If you don't have multiple items in your Horizontal RecyclerView, you shall use Horizontal ScrollView instead.