Develop Reference

Android: Scroll whole fragment with ListView inside

I have the following structure in my fragment layout file:
- ScrollView
- ConstraintLayout
- CardView
- *some stuff here*
- CardView
- ListView
- *list header*
- *list items generated with a custom adapter*
If I remove the outer ScrollView, I can see the whole content of the ListView, and if it's bigger than the remaining space for the 2nd CardView, I can scroll it. The 1st CardView stays in place, but the content of the 2nd one is scrollable.
However, I would like to scroll the whole fragment. I would like the 2nd CardView to expand and contain the whole ListView, and if I scroll up or down, the 1st one moves as well.
I tried several combinations of height settings. No point of showing you my actual layout XML, because it's a mess. I would like a clean slate. Is it possible to achieve?
EDIT:
I know the ListView is a scroll container itself, but I think it's a pretty common need to scroll the whole thing, so I can't understand why it's so hard to make it work.

Alright, after combining multiple answers, I have the solution that I needed.
First
I needed to use a NestedScrollView instead of a regular ScrollView.
It solves the conflict between the two scroll containers (ScrollView and ListView).
Reference: Android: ScrollView vs NestedScrollView
NOTE: My list content is dynamic, so it can be too short to fill the remaining space. I had to set android:fillViewport="true" on the NestedScrollView. If the list is longer than the remaining space, it will not cause any trouble.
layout.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.core.widget.NestedScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fillViewport="true">
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.cardview.widget.CardView
android:id="#+id/card1"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<!-- NOTE: constraints properties are missing from here for easier reading -->
<!-- card content here -->
</androidx.cardview.widget.CardView>
<androidx.cardview.widget.CardView
android:id="#+id/card2"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<!-- NOTE: constraints properties are missing from here for easier reading -->
<ListView
android:id="#+id/list"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
<!-- NOTE: this will change in step 3 -->
</androidx.cardview.widget.CardView>
</androidx.constraintlayout.widget.ConstraintLayout>
</androidx.core.widget.NestedScrollView>
Second
Following the steps above will make the ListView collapse to the height of its first item. To solve this, I needed to create a subclass from ListView and override its onMeasure() method, so it can calculate the proper height at runtime.
Reference: Android - NestedScrollView which contains ExpandableListView doesn't scroll when expanded
NonScrollListView.java
package my.package.name
import ...
public class NonScrollListView extends ListView {
// NOTE: right click -> create constructors matching super
#Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int heightMeasureSpec_custom = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2, MeasureSpec.AT_MOST);
super.onMeasure(widthMeasureSpec, heightMeasureSpec_custom);
ViewGroup.LayoutParams params = getLayoutParams();
params.height = getMeasuredHeight();
}
}
Third
I needed to use my custom View instead of the regular ListView in my layout XML.
layout.xml excerpt
<my.package.name.NonScrollListView
android:id="#+id/list"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
This way I managed to make it work. Both cards move together on scroll, even if I tap the ListView area.
I don't know whether it causes performance issues with really long lists, because mine contains a few dozen items at most, but I have no problem on a low end Galaxy A20e.

Loading items into a RecyclerView with stackFromEnd = true doesn't scroll to bottom

I have a chat app and i'm trying to ensure that when the user opens the screen the items display from the bottom with the most recent right above the input area. I've used a custom view for the input area and both the recycler and the custom view are within a ConstraintLayout.
My problem is that when I load items into the list, if the number of items is greater than the size of the recycler, it will not fully show the last item. When I make the input area visibility = Gone then the items display properly at the bottom. It's almost like the recyclers LinearLayoutManager thinks that the height of the Recycler is of the screen without the input field. I've manually printed out the size of the views and used layout inspector to ensure that the recycler is indeed drawn in the correct location (above the input and below the navigation bar).
What could be causing such an issue? I should note that whenever you click on a Linkified text in a chat bubble that the list scrolls a small amount equal to the offset that's incorrect when you open the screen. Clearly something is not measuring right here and not sure where to begin.
I should also note that if I try to add a post with smoothScroll it will go to the end of the list but then whenever a new item appears in the list from sending a message the items above the most recently added one seem to jump up a little with an unnecessary animation. It's like the last item in the list is in some special state?
if you're curious this is my scrolling function:
private fun scrollToFirstItem(dueToKeyboard: Boolean = false) {
val stackingFromEnd = (recyclerView.layoutManager as LinearLayoutManager).stackFromEnd
if (stackingFromEnd) {
val firstPosition = recyclerView.adapter?.itemCount?: 0 - 1
if (dueToKeyboard ) {
recyclerView.scrollBy(0, Integer.MAX_VALUE)
} else {
recyclerView.scrollToPosition(firstPosition)
}
recyclerView.post { recyclerView.smoothScrollToPosition(firstPosition) }
} else {
recyclerView.scrollToPosition(0)
}
}
And my xml for my fragment:
<androidx.constraintlayout.widget.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<include
android:id="#+id/searchView"
layout="#layout/compose_new_message_include"/>
<com.airbnb.epoxy.EpoxyRecyclerView
android:id="#+id/conversationEpoxyRV"
android:layout_width="match_parent"
android:layout_height="0dp"
android:scrollbars="vertical"
app:layout_constraintTop_toBottomOf="#id/searchView"
app:layout_constraintBottom_toTopOf="#id/composeView"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
tools:listitem="#layout/conversation_item_inbound"/>
<include layout="#layout/conversation_pip_view"
android:id="#+id/selectedMediaContainer"/>
<****.ComposeView
android:id="#+id/composeView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintBottom_toBottomOf="parent"/>
</androidx.constraintlayout.widget.ConstraintLayout>
Any help is appreciated, I'm so lost..

To me this feels like more of an issue in the layout rather than in the scrolling function. I hope that this can be resolved easily if you use a Relative Layout instead of a Linear Layout. So in case if it may be helpful, i'll add my solution below using a Relative Layout.
<RelativeLayout
android:id="#+id/layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recycle_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#id/input_field">
</androidx.recyclerview.widget.RecyclerView>
<EditText
android:id="#+id/input_field"
android:layout_width="match_parent"
android:layout_height="50dp"
android:layout_alignParentBottom="true"/>
</RelativeLayout>
So in case if it is not clear what i have done, an EditText element is set to align to the bottom of parent which is a Relative Layout. Then a RecyclerView is added so that RecylerView will be always constraint above the EditText but not overlapped.

Everything looks fine, except the restrictions you added to recycleview design, I see that you are setting the recycleview to top of searchView app:layout_constraintTop_toBottomOf="#id/searchView" while the searchView view is not restricted as should it be.
It's better when using ConstraintLayout to restrict every view inorder avoid unexpected behaviors, because every view has a relation with other view will be effected with other view (x, y), therefore your searchView should be look like:
<include
android:id="#+id/searchView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
layout="#layout/compose_new_message_include"/>

Give the size of arraylist of your data to smoothScrollToPosition
var linearLayoutManager = LinearLayoutManager(context)
recyclerView.layoutManager=linearLayoutManager
recyclerView.adapter=adapter
linearLayoutManager.setStackFromEnd(true)
adapter.notifyDataSetChanged()
recyclerView.smoothScrollToPosition(dataMsgs.size())

I had a similar problem some years back and I solved it with scrollToPositionWithOffset (support library). Of course this was before constraint was used....
I kept my newer items at the bottom, too. The code I used for scrolling after inserting an item was:
((LinearLayoutManager) layoutManager).scrollToPositionWithOffset(getItemCount() - 1, 0);
To scroll and adjust the awkward positioning after removing an item, I used:
View vTopCard = layoutManager.getChildAt(0);
// Get its adapter position
final int topCardPos = layoutManager.getPosition(vTopCard);
// Get top of card position
int topOffset = layoutManager.getDecoratedTop(vTopCard);
int cardMargin = (int) getResources().getDimension(R.dimen.card_vertical_margin);
((LinearLayoutManager) layoutManager).scrollToPositionWithOffset(topCardPos, topOffset - cardMargin);
The getDecoratedTop helps with the "bounce" and final positioning, as does factoring the vertical margin.
I hope this helps (at least part of your issue)! Like I said, this is old code (when I was learning to program Android and Java at the same time), so if I left something out, let me know and I'll reexamine the app's code in more detail (though, I'll have to find the time).
Good luck!

Avoid scrolling of first row and first column in recyclerview gridlayoutmanager

Created a two way scrollable gridlayout for a TV app
view structure from layout file
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#021257"
android:orientation="vertical">
<HorizontalScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fillViewport="true">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/rvThumbnail"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#021257"
android:orientation="vertical"/>
</LinearLayout>
</HorizontalScrollView>
</LinearLayout>
so i have used a gridlayoutmanager(orientation vertical) and spancount being 49 (24hrs *2)+1 for images displaying column. The first row is to display timeline divided into half hour slots and first column is to display channels, each channel will have its own programs running under different time slots. Now that i achieved to scroll the gridlayout both ways, now i have two more things to do.
1) When scrolled horizontally, the channels column(first column) also gets scrolled and hence gets hidden(it has to scroll vertically though, since there can be 20+ channels). Now i need to make this column static wen scrolling horizontally and rest other columns must scroll normally
2) When scrolled vertically, the timeline row (first row) also gets scrolled and hence gets hidden(it has to scroll horizontally though, since the row has to display 24 hrs). Now i need to make this row static wen scrolling vertically and rest other rows must scroll normally.
Is this possible to achieve ? I appreciate your help

The Feasible approach will be to go with three recycle view
a)Vertical recycle view for channel listing
b)Horizontal recycle view for Timing listing
c)Recycle view with grid layout manager for the data
Use scrollChange listener of grid recycle view(Recycle view used for data)
/**
* Use scroll values
*/
public void setScroll() {
mDataRecycleView.setOnScrollChangeListener(new View.OnScrollChangeListener() {
#Override
public void onScrollChange(View v, int scrollX, int scrollY, int oldScrollX, int oldScrollY) {
//you can now play on scroll value of this recycle view and change the scroll value of other recycle views.
// you can get your view here and also know the value of view so based on value you can handle it here so it's very easy.
}
});
}
Try and let me know if this approach works for you and incase any query then comment below so we can solved your problem.

Try TableView project from Github.
TableView is a powerful Android library for displaying complex data
structures and rendering tabular data composed of rows, columns and
cells. TableView relies on a separate model object to hold and
represent the data it displays. This repository also contains a sample
app that is designed to show you how to create your own TableView in
your application.
Get concept from this project and modify what you want.
Hope this explanation helps you :)

Recyclerview binds all views at the same time

I have a vertical recyclerview (with a GridLayoutManager) inside another recyclerview (with LinearLayoutManager). The problem I am facing right now is that, the inner recyclerview (with GridLayoutManager) binds all of it's items at the same time, even the views that are not on the screen at the moment (onBindViewHolder() gets called for all of its items).
To give you more information, in my layout file, I put height of my recycler view as wrap_content.
I think the problem is, since there are 2 nested vertically recyclerviews, when the parent RV wants to measure its children and the children is another RV, in onMeasure() it computes the size needed for the entire RV, not just the portion that it wants to bind on the screen.
Any idea how to solve this?
Here is the layout file for my outer recyclerview:
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:id="#+id/component_list"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</FrameLayout>
And here is the code for my inner recyclerview:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/container"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingTop="#dimen/gutter"
android:paddingBottom="#dimen/gutter">
<TextView
android:id="#+id/title_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="#dimen/gutter"
android:textSize="30sp"
android:textColor="#android:color/white"
android:fontFamily="sans-serif-thin"/>
<android.support.v7.widget.RecyclerView
android:id="#+id/my_slider"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
P.S.: I'm using this adapter delegate for my outer recyclerview:
https://github.com/sockeqwe/AdapterDelegates

I think nested recyclerviews are a very bad idea. When i try to scroll, which recyclerview has to respond the the scolling, the parrent or child.
That is why I think you are looking for the ExpandableListView? That's limited to only two levels of listings, but that sounds like it would work for your needs). It also solves the soling issue.
It would look something like this:
EDIT: even nested ExpandableListViews are possible:
EDIT: check this lib for horizontal scroling

This is a known bug.
You should not put a RecyclerView inside another RecyclerView because RecyclerView gives its children infinite space. Hence the inner RecyclerView keeps measuring till the dataset is exhausted. Try setting setAutoMeasureEnabled(false) to false on layout manager or you can solve this problem by using a wrapper adapter instead of inner recycler view.

The first thing you need to know is that, when you nest scrolling layouts, the inner ones will get infinity allowed height, effectively making them wrap_content. There is in fact a relatively easy way to fix this problem.
Say I had two nested RecyclerViews such as these, in this case vertically oriented.
<RecyclerView
android:layout_height="match_parent"
android:layout_width="match_parent"
android:orientation="vertical>
<View .../>
<!-- other stuff -->
<RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"/>
</RecyclerView>
The inner recyclerView here will bind all of it's children immediately every time because, from it's position, your screen will have infinite height.
The solution is to set the height of your inner recyclerview to some static value, not wrap_content or match parent, as either of those will simply fill up the outer recyclerview with one view that will all be bound at once due to it's large height. If you make the height of the inner recyclerview the same as the display's height, you should see your problem go away.
Here is an implementation that will not bind all children at once:
<RecyclerView
android:layout_height="match_parent"
android:layout_width="match_parent"
android:orientation="vertical>
<View .../>
<!-- other stuff -->
<RecyclerView
android:layout_width="match_parent"
android:layout_height="#dimen/screen_height"
android:orientation="vertical"/>
</RecyclerView>
Note the layout_height of the inner RecyclerView is now a fixed value pulled from the dimensions file. You yourself will have to come up with a reasonable value to put there.
Side Note: In order to make all of this work and for scrolling to work properly, you may have to play around with the parameter: NestedScrollingEnabled in your RecyclerViews - there are several known bugs relating to this that you may need to work around.
i.e.: innerRecyclerView.setHasFixedSize(true); and innerRecyclerView.setNestedScrollingEnabled(false).

so what happens here when you place a scrollview(no fixed size because of wrap content) inside another scrollview(again no fixed size because of wrap content),both nested scroll view fails to render.
So there is two solutions--
1- Either you will have to think of alternative solution for nested scrollviews
2- You can give outside recyclerview cell fixed height so that inside recycler view can get some fixed layout to render itself.

I could solve my issue by using only one Recyclerview, where it has a grid layout, and based on the component items i'm adding into it, i change the spancount for that. Basically instead of adding the inner recyclerview, i add the items that were supposed to go to the inner recyclerview, to the outer recyclerview.

Recyclerview inside Nested Scrollview scroll but does not fast scroll like normal Recyclerview or Nested Scrollview

I am using RecyclerView inside NestedScrollView and it works. But when I use RecyclerView inside LinearLayout or something, it scroll in various speed depending on gesture. The scroll listen to gesture and if I slide up only a bit, then it scroll a little bit while if I slide up really fast, then it scroll really fast. Now my problem is that RecyclerView inside NestedScrollView certainly scroll but fast scroll does not work. However I slide up fast or slow, RecyclerView or NestedScrollView only scroll a little bit.
How can I make my NestedScrollView or RecyclerView inside that scroll view scroll in various speed?

try
recyclerView.setNestedScrollingEnabled(false);

By default setNestedScrollingEnabled works only after API-21.
You can use ViewCompat.setNestedScrollingEnabled(recyclerView, false); to disable nested scrolling for before and after API-21(Lollipop). Link to documentation.

I was working on android 16 where this was not possible to use setNestedSCrollEnabled method,
What I end up doing to stop RecyclerView from handling Scrolls.
Like in LinerLayoutManager i made canScrollHorizontally, canScrollVertically to return false by default.
myRecyclerView.setLayoutManager(new LinearLayoutManager(getContext(), LinearLayoutManager.VERTICAL, false){
#Override
public boolean canScrollHorizontally() {
return false;
}
#Override
public boolean canScrollVertically() {
return false;
}
});

After several iterations, I came up with a solution.
If you are using RecyclerView, then:
recyclerView.setNestedScrollingEnabled(false);
If you are using LinearLayout inside NestedScrollingView, take the LinearLayout inside a normal ScrollView and then set its scrolling to
scrollView.setNestedScrollingEnabled(false);

android:overScrollMode="never
<android.support.v4.widget.NestedScrollView
android:id="#+id/nestedScrollView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:overScrollMode="never">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<android.support.v7.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
</android.support.v4.widget.NestedScrollView>

You can use ScrollView with ExtendRecyclerView class that overrides the onMeasure method. That works for me!
#Override
protected void onMeasure(int widthSpec, int heightSpec) {
int expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2, MeasureSpec.AT_MOST);
super.onMeasure(widthSpec, expandSpec);
}

recyclerView.setNestedScrollingEnabled(false);
Will be useful sometimes.But it is not advisable for all the times.because it disables view recycling feature in recylcer view.
Alternatives:
Try CollapsiveToolbarLayout with Recycler view.
put other views in collapsiveTollbar layout.

I also met this problem.
And upgrade to 26.1.0 fix it.

In My Case i placed all images in drawable folder insted of drawable-xxxhdpi folder thats why my screen UI is lagging.

This is WAI. The NestedScrollView measures its children with the Spec "Unspecified". The child can grow as much as it wants too.
This essentially equates the height of NSV and RV. So as far as the RV is concerned, it believes that it is completely displayed.
Wrap your RV with an LL and give your RV a height. The LL would not set the measure spec to be UNSPECIFIED so the RV would correctly scroll within its set height of whatever DPs you provide.
The only downside of this method is that you will not be able to do a match parent on your RV.

You should wrap recycler view in any layout like LinearLayout and set RecyclerView size to constant, like 800dp. This will enable smooth scroll and recycler view will still recycler views during scroll.
<android.support.v4.widget.NestedScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="800dp"
app:layout_behavior="#string/appbar_scrolling_view_behavior"/>
</LinearLayout>