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ScrollView is keeping scrolling although the layout is empty

The problem is that the ScrollView scrolls till it completes all the content of my layout, then it keeps scrolling and shows empty layout. It keeps scrolling for a long empty length. I guess the problem is in using the RecyclerView inside a ScrollView, and I just know that this will result in a poor UI experience, but the point now is to make it work
Here is the component tree of my layout
And here is the snippet of the xml code for the part of the ScrollView
<ScrollView
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="#color/white_smoke"
android:fillViewport="true">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical">
<androidx.constraintlayout.widget.ConstraintLayout...>
<LinearLayout
android:id="#+id/frameLayout2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/comments_recycler_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/white_smoke" />
</LinearLayout>
</LinearLayout>

After trying a few solutions. Wrapping the RecyclerView in a RelativeLayout instead of LinearLayout has solved the problem for me. A final thing to not forget, do not use RecyclerView in a ScrollView as the RecyclerView will not recycle its views. You can do that if you are sure that there are no many items in the RecyclerView.

Show a horizontally large background in back of Recyclerview

I have a background image with a long width which I want to be in back of a Recyclerview with 8 item in it(Recyclerview). This is possible only with a horizontal-scrollview which I coded below but Is there any way to not use horizontal scrollview and have a same result?
<HorizontalScrollView
android:id="#+id/HSV"
android:layout_width="wrap_content"
android:layout_height="match_parent">
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:background="#drawable/back"
android:paddingLeft="2.5dp"
android:paddingRight="2.5dp"
android:orientation="vertical">
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</RelativeLayout>
</HorizontalScrollView>
with the above code I have the desired output, but as I remove the HorizontalScrollView The image is compressing in width and loose its shape I want the image scroll as I scroll the recyclerview
That is The picture I want:
![in Background is the aforementioned image and this eight Item are in recycler view and I want as the items finishing the background image is finishing too.
]1

Design like this in layout.And pass layout of card in image to adapter in Android.Set background to Constraint layout ore Recyclerview. When you have Recyclerview no need to add Horizontal Scrollview. Just pass Layout manager as Horizontal
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
android:background="#color/secondaryColor"
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.recyclerview.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"/>
</androidx.constraintlayout.widget.ConstraintLayout>idget.ConstraintLayout>

I wonder if I have got your query right, so you want your RecyclerView to be scrolling horizontally. I would suggest to use the LinearLayoutManager for the same, so that you can pass the Scrolling constant to Horizontal in the arguments of LinearLayoutManager.
To read about it, please go ahead and read it LinearLayoutManager
And when you get it, just do it like this in you Java Class.
RecyclerView.setLayoutManager(new LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, true));
I have this youtube link for you too, if you don't get it what you want. Here you will get the full demo of how to do it, and achieve it. Horizontal RecyclerView
I hope that will answer your query. Thanks :)

RecyclerView (wrap_content) inside of a BottomSheetDialogFragment

I'm facing a tricky situation here and I don't know how to solve this problem.
In my project I have a custom BottomSheetDialogFragment and in the layout a FrameLayout to add or replace Fragments.
Now I have a Fragment and inside I have a RecyclerView with the height:="wrap_content" because I want the BottomSheetDialogFragment only use the necessary space. Everything looks great, the problem appear when I put another view inside of the same layout and set the RecyclerView bellow or above of that view.
The RecyclerView ignores the size of the other view (or views) and always grows to the max screen size, and then it's no possible to see a few elements and even scroll.
I saw a solution, some developers are suggesting to add paddingBottom equals to the height of the view. But in my case doesn't works because I want to have a dynamic solution.
Above I'll share a few images of the problem and GitHub Repository with a sample.
Thanks for your attention!

I've manage to do what you need just need to use this as your fragment_sample.xml:
<LinearLayout 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="wrap_content"
android:orientation="vertical">
<android.support.v7.widget.RecyclerView
android:id="#+id/rclItems"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
app:layoutManager="android.support.v7.widget.LinearLayoutManager"/>
<Button
android:id="#+id/btnAddMoreItems"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#+id/rclItems"
android:text="#string/add_1_item"/>
</LinearLayout>
Explanation
Using a LinearLayout gives you the ability to work with weight, and the vertical orientation allows you to place an item below the other. The weight on the recyclerview will increase the height of it as needed until filling the screen. The next item you add would be added to the recyclerview but you'll need to scroll the list to see it

The android developers blog says that :-
The scrolling containers in your bottom sheet must support nested scrolling .
Try changing your fragment_sample.xml as below to make the recyclerview scroll working and to make the add button persistent.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
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="wrap_content">
<android.support.v4.widget.NestedScrollView
android:layout_width="match_parent"
android:id="#+id/next"
android:layout_above="#id/btnAddMoreItems"
android:layout_height="wrap_content">
<android.support.v7.widget.RecyclerView
android:id="#+id/rclItems"
android:layout_width="match_parent"
android:layout_height="wrap_content"
/>
</android.support.v4.widget.NestedScrollView>
<Button
android:id="#+id/btnAddMoreItems"
android:layout_width="match_parent"
android:layout_alignParentBottom="true"
android:layout_height="wrap_content"
android:text="#string/add_1_item"/>
</RelativeLayout>
Note: making bottomsheet layout a child view of CoordinatorLayout will allow you to get the implement BottomSheetBehavior and recieve its transitions callbacks .

RecyclerView inside NestedScrollView inside SwipeRefreshLayout doesn't scroll smoothly

Here's my layout.
<android.support.v4.widget.SwipeRefreshLayout
android:id="#+id/activity_main_swipe_refresh_layout"
android:layout_width="match_parent"
android:layout_marginBottom="45dp"
android:layout_height="wrap_content">
<android.support.v4.widget.NestedScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:focusableInTouchMode="true">
<Button
android:layout_width="300dp"
android:layout_height="100dp"
android:id="#+id/noob_button"
android:text="haha" />
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="#+id/noob_button"
android:orientation="vertical"
android:clipToPadding="false"
android:scrollbars="vertical" />
</RelativeLayout>
</android.support.v4.widget.NestedScrollView>
</android.support.v4.widget.SwipeRefreshLayout>
This is all inside RelativeLayout.
I have set recyclerview.setNestedScrol..(false);
It still hangs and if I set fixed height of the RecyclerView it doesn't hang. It scrolls but the scroll is not smooth.

You do not actually need a RecyclerView inside a NestedScrollView. As far as I have understood your question, you need a Button and a RecyclerView under the button. So you might consider adding the Button as the header of the RecyclerView which is neater implementation.
If you are thinking of adding a header in your RecyclerView please see my answer here on how this can be achieved.
I have explained how a footer can be added. The same rule applies for adding a header view as well. Please let me know if you have any further questions regarding this.

Issue with RecyclerView

I made a recycler view with linear layout manager to display items.
This is my RecyclerView.
<com.example.Recycler.RecyclerView
android:id="#+id/recycler1"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
And this is the item layout that I'm using for RecyclerView.
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:padding="5dp"
android:layout_height="wrap_content">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="16dp"
android:id="#+id/content"/>
</LinearLayout>
Everything works well, but I've got a small issue. The data which I fill the recycler with are 10 items.
The recycler in some devices displays the 10 items, in other devices, it displays only 3 items and make scrollbars to show the rest.
I tried to use android:scrollbars="none" in the recycler, but it made the recycler show only 3 items.
I tried also to use setNestedScrollingEnabled(false); but it didn't work either.
Any help?

You should make height for RecyclerView to match_parent.
Here is the code should be:
<com.example.Recycler.RecyclerView
android:id="#+id/recycler1"
android:layout_width="match_parent"
android:layout_height="match_parent"/>

Use RecyclerView android.support.v7.widget.RecyclerView instead of your custom com.example.Recycler.RecyclerView
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler1"
android:scrollbars="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
</android.support.v7.widget.RecyclerView>
The RecyclerView widget is a part of the v7 Support Libraries. To use this widget in your project, add below Gradle dependency to your app's module:
dependencies {
...
compile 'com.android.support:recyclerview-v7:25.0.+'
}