How can I make sticky headers in RecyclerView Without external lib

Question

I want to fix my header views in the top of the screen like in the image below and without using external libraries     In my case  I don t want to do it alphabetically  I have two different types of views  Header and normal   I only want to fix to the top  the last header

User · Answer

Easiest way is to just create an Item Decoration for your RecyclerView.

import android.graphics.Canvas;
import android.graphics.Rect;
import android.support.annotation.NonNull;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

public class RecyclerSectionItemDecoration extends RecyclerView.ItemDecoration {

private final int             headerOffset;
private final boolean         sticky;
private final SectionCallback sectionCallback;

private View     headerView;
private TextView header;

public RecyclerSectionItemDecoration(int headerHeight, boolean sticky, @NonNull SectionCallback sectionCallback) {
    headerOffset = headerHeight;
    this.sticky = sticky;
    this.sectionCallback = sectionCallback;
}

@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
    super.getItemOffsets(outRect, view, parent, state);

    int pos = parent.getChildAdapterPosition(view);
    if (sectionCallback.isSection(pos)) {
        outRect.top = headerOffset;
    }
}

@Override
public void onDrawOver(Canvas c, RecyclerView parent, RecyclerView.State state) {
    super.onDrawOver(c,
                     parent,
                     state);

    if (headerView == null) {
        headerView = inflateHeaderView(parent);
        header = (TextView) headerView.findViewById(R.id.list_item_section_text);
        fixLayoutSize(headerView,
                      parent);
    }

    CharSequence previousHeader = "";
    for (int i = 0; i < parent.getChildCount(); i++) {
        View child = parent.getChildAt(i);
        final int position = parent.getChildAdapterPosition(child);

        CharSequence title = sectionCallback.getSectionHeader(position);
        header.setText(title);
        if (!previousHeader.equals(title) || sectionCallback.isSection(position)) {
            drawHeader(c,
                       child,
                       headerView);
            previousHeader = title;
        }
    }
}

private void drawHeader(Canvas c, View child, View headerView) {
    c.save();
    if (sticky) {
        c.translate(0,
                    Math.max(0,
                             child.getTop() - headerView.getHeight()));
    } else {
        c.translate(0,
                    child.getTop() - headerView.getHeight());
    }
    headerView.draw(c);
    c.restore();
}

private View inflateHeaderView(RecyclerView parent) {
    return LayoutInflater.from(parent.getContext())
                         .inflate(R.layout.recycler_section_header,
                                  parent,
                                  false);
}

/**
 * Measures the header view to make sure its size is greater than 0 and will be drawn
 * https://yoda.entelect.co.za/view/9627/how-to-android-recyclerview-item-decorations
 */
private void fixLayoutSize(View view, ViewGroup parent) {
    int widthSpec = View.MeasureSpec.makeMeasureSpec(parent.getWidth(),
                                                     View.MeasureSpec.EXACTLY);
    int heightSpec = View.MeasureSpec.makeMeasureSpec(parent.getHeight(),
                                                      View.MeasureSpec.UNSPECIFIED);

    int childWidth = ViewGroup.getChildMeasureSpec(widthSpec,
                                                   parent.getPaddingLeft() + parent.getPaddingRight(),
                                                   view.getLayoutParams().width);
    int childHeight = ViewGroup.getChildMeasureSpec(heightSpec,
                                                    parent.getPaddingTop() + parent.getPaddingBottom(),
                                                    view.getLayoutParams().height);

    view.measure(childWidth,
                 childHeight);

    view.layout(0,
                0,
                view.getMeasuredWidth(),
                view.getMeasuredHeight());
}

public interface SectionCallback {

    boolean isSection(int position);

    CharSequence getSectionHeader(int position);
}

}

XML for your header in recycler_section_header.xml:

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/list_item_section_text"
    android:layout_width="match_parent"
    android:layout_height="@dimen/recycler_section_header_height"
    android:background="@android:color/black"
    android:paddingLeft="10dp"
    android:paddingRight="10dp"
    android:textColor="@android:color/white"
    android:textSize="14sp"
/>

And finally to add the Item Decoration to your RecyclerView:

RecyclerSectionItemDecoration sectionItemDecoration =
        new RecyclerSectionItemDecoration(getResources().getDimensionPixelSize(R.dimen.recycler_section_header_height),
                                          true, // true for sticky, false for not
                                          new RecyclerSectionItemDecoration.SectionCallback() {
                                              @Override
                                              public boolean isSection(int position) {
                                                  return position == 0
                                                      || people.get(position)
                                                               .getLastName()
                                                               .charAt(0) != people.get(position - 1)
                                                                                   .getLastName()
                                                                                   .charAt(0);
                                              }

                                              @Override
                                              public CharSequence getSectionHeader(int position) {
                                                  return people.get(position)
                                                               .getLastName()
                                                               .subSequence(0,
                                                                            1);
                                              }
                                          });
    recyclerView.addItemDecoration(sectionItemDecoration);

With this Item Decoration you can either make the header pinned/sticky or not with just a boolean when creating the Item Decoration.

You can find a complete working example on github: https://github.com/paetztm/recycler_view_headers

User · Answer

to anyone looking for solution to the flickering blinking issue when you already have DividerItemDecoration  i seem to have solved it like this   override fun onDrawOver                      code from before           do NOT return on null         val childInContact   getChildInContact recyclerView  currentHeader bottom            add null check         if  childInContact    null  amp  amp  mHeaderListener isHeader recyclerView getChildAdapterPosition childInContact                          moveHeader                  return               drawHeader          this seems to be working but can anyone confirm i did not break anything else

User · Answer

The answer has already been here  If you don t want to use any library  you can follow these steps    Sort list with data by name Iterate via list with data  and in place when current s item first letter    first letter of next item  insert  special  kind of object  Inside your Adapter place special view when item is  special     Explanation   In onCreateViewHolder method we can check viewType and depending on the value  our  special  kind  inflate a special layout   For example   public static final int TITLE   0  public static final int ITEM   1    Override public RecyclerView ViewHolder onCreateViewHolder ViewGroup parent  int viewType        if  context    null            context   parent getContext              if  viewType    TITLE            view   LayoutInflater from context  inflate R layout recycler adapter title  parent false           return new TitleElement view         else if  viewType    ITEM            view   LayoutInflater from context  inflate R layout recycler adapter item  parent false           return new ItemElement view             return null      where class ItemElement and class TitleElement can look like ordinary ViewHolder    public class ItemElement extends RecyclerView ViewHolder     TextView text   public ItemElement View view        super view        text    TextView  view findViewById R id text        So the idea of all of that is interesting  But i am interested if it s effectively  cause we need to sort the data list  And i think this will take the speed down  If any thoughts about it  please write me     And also the opened question   is how to hold the  special  layout on the top  while the items are recycling  Maybe combine all of that with CoordinatorLayout

User · Answer

you can get sticky header functionality by copying these 2 files into your project  i had no issues with this implementation   can interact with the sticy header  tap long press swipe  the sticky header hides and reveals itself properly   even if each view holder has a different height  some other answers here don t handle that properly  causing the wrong headers to show  or the headers to jump up and down   see an example of the 2 files being used in this small github project i whipped up

User · Answer

Here I will explain how to do it without an external library  It will be a very long post  so brace yourself   First of all  let me acknowledge  tim paetz whose post inspired me to set off to a journey of implementing my own sticky headers using ItemDecorations  I borrowed some parts of his code in my implementation   As you might have already experienced  if you attempted to do it yourself  it is very hard to find a good explanation of HOW to actually do it with the ItemDecoration technique  I mean  what are the steps  What is the logic behind it  How do I make the header stick on top of the list  Not knowing answers to these questions is what makes others to use external libraries  while doing it yourself with the use of ItemDecoration is pretty easy   Initial conditions   You dataset should be a list of items of different type  not in a  Java types  sense  but in a  header item  types sense   Your list should be already sorted  Every item in the list should be of certain type - there should be a header item related to it  Very first item in the list must be a header item    Here I provide full code for my RecyclerView ItemDecoration called HeaderItemDecoration  Then I explain the steps taken in detail   public class HeaderItemDecoration extends RecyclerView ItemDecoration     private StickyHeaderInterface mListener   private int mStickyHeaderHeight    public HeaderItemDecoration RecyclerView recyclerView   NonNull StickyHeaderInterface listener      mListener   listener        On Sticky Header Click   recyclerView addOnItemTouchListener new RecyclerView OnItemTouchListener        public boolean onInterceptTouchEvent RecyclerView recyclerView  MotionEvent motionEvent        if  motionEvent getY    lt   mStickyHeaderHeight            Handle the clicks on the header here          return true            return false           public void onTouchEvent RecyclerView recyclerView  MotionEvent motionEvent              public void onRequestDisallowInterceptTouchEvent boolean disallowIntercept                      Override  public void onDrawOver Canvas c  RecyclerView parent  RecyclerView State state      super onDrawOver c  parent  state      View topChild   parent getChildAt 0     if  Util isNull topChild        return         int topChildPosition   parent getChildAdapterPosition topChild     if  topChildPosition    RecyclerView NO POSITION       return         View currentHeader   getHeaderViewForItem topChildPosition  parent     fixLayoutSize parent  currentHeader     int contactPoint   currentHeader getBottom      View childInContact   getChildInContact parent  contactPoint     if  Util isNull childInContact        return         if  mListener isHeader parent getChildAdapterPosition childInContact         moveHeader c  currentHeader  childInContact      return         drawHeader c  currentHeader        private View getHeaderViewForItem int itemPosition  RecyclerView parent      int headerPosition   mListener getHeaderPositionForItem itemPosition     int layoutResId   mListener getHeaderLayout headerPosition     View header   LayoutInflater from parent getContext    inflate layoutResId  parent  false     mListener bindHeaderData header  headerPosition     return header       private void drawHeader Canvas c  View header      c save      c translate 0  0     header draw c     c restore         private void moveHeader Canvas c  View currentHeader  View nextHeader      c save      c translate 0  nextHeader getTop   - currentHeader getHeight       currentHeader draw c     c restore         private View getChildInContact RecyclerView parent  int contactPoint      View childInContact   null    for  int i   0  i  lt  parent getChildCount    i         View child   parent getChildAt i      if  child getBottom    gt  contactPoint        if  child getTop    lt   contactPoint            This child overlaps the contactPoint      childInContact   child       break                   return childInContact               Properly measures and layouts the top sticky header       param parent ViewGroup  RecyclerView in this case        private void fixLayoutSize ViewGroup parent  View view          Specs for parent  RecyclerView    int widthSpec   View MeasureSpec makeMeasureSpec parent getWidth    View MeasureSpec EXACTLY     int heightSpec   View MeasureSpec makeMeasureSpec parent getHeight    View MeasureSpec UNSPECIFIED         Specs for children  headers    int childWidthSpec   ViewGroup getChildMeasureSpec widthSpec  parent getPaddingLeft     parent getPaddingRight    view getLayoutParams   width     int childHeightSpec   ViewGroup getChildMeasureSpec heightSpec  parent getPaddingTop     parent getPaddingBottom    view getLayoutParams   height      view measure childWidthSpec  childHeightSpec      view layout 0  0  view getMeasuredWidth    mStickyHeaderHeight   view getMeasuredHeight          public interface StickyHeaderInterface               This method gets called by   link HeaderItemDecoration  to fetch the position of the header item in the adapter      that is used for  represents  item at specified position        param itemPosition int  Adapter s position of the item for which to do the search of the position of the header item        return int  Position of the header item in the adapter          int getHeaderPositionForItem int itemPosition               This method gets called by   link HeaderItemDecoration  to get layout resource id for the header item at specified adapter s position        param headerPosition int  Position of the header item in the adapter        return int  Layout resource id          int getHeaderLayout int headerPosition               This method gets called by   link HeaderItemDecoration  to setup the header View        param header View  Header to set the data on        param headerPosition int  Position of the header item in the adapter          void bindHeaderData View header  int headerPosition               This method gets called by   link HeaderItemDecoration  to verify whether the item represents a header        param itemPosition int        return true  if item at the specified adapter s position represents a header          boolean isHeader int itemPosition          Business logic  So  how do I make it stick   You don t  You can t make a RecyclerView s item of your choice just stop and stick on top  unless you are a guru of custom layouts and you know 12 000  lines of code for a RecyclerView by heart  So  as it always goes with the UI design  if you can t make something  fake it  You just draw the header on top of everything using Canvas  You also should know which items the user can see at the moment  It just happens  that ItemDecoration can provide you with both the Canvas and information about visible items  With this  here are basic steps    In onDrawOver method of RecyclerView ItemDecoration get the very first  top  item that is visible to the user       View topChild   parent getChildAt 0    Determine which header represents it           int topChildPosition   parent getChildAdapterPosition topChild       View currentHeader   getHeaderViewForItem topChildPosition  parent    Draw the appropriate header on top of the RecyclerView by using drawHeader   method    I also want to implement the behavior when the new upcoming header meets the top one  it should seem as the upcoming header gently pushes the top current header out of the view and takes his place eventually   Same technique of  drawing on top of everything  applies here    Determine when the top  stuck  header meets the new upcoming one           View childInContact   getChildInContact parent  contactPoint    Get this contact point  that is the bottom of the sticky header your drew and the top of the upcoming header            int contactPoint   currentHeader getBottom     If the item in the list is trespassing this  contact point   redraw your sticky header so its bottom will be at the top of the trespassing item  You achieve this with translate   method of the Canvas  As the result  the starting point of the top header will be out of visible area  and it will seem as  being pushed out by the upcoming header   When it is completely gone  draw the new header on top           if  childInContact    null            if  mListener isHeader parent getChildAdapterPosition childInContact                  moveHeader c  currentHeader  childInContact             else               drawHeader c  currentHeader                      The rest is explained by comments and thorough annotations in piece of code I provided   The usage is straight forward   mRecyclerView addItemDecoration new HeaderItemDecoration  HeaderItemDecoration StickyHeaderInterface  mAdapter      Your mAdapter must implement StickyHeaderInterface for it to work  The implementation depends on the data you have   Finally  here I provide a gif with a half-transparent headers  so you can grasp the idea and actually see what is going on under the hood   Here is the illustration of  just draw on top of everything  concept  You can see that there are two items  header 1  - one that we draw and stays on top in a stuck position  and the other one that comes from the dataset and moves with all the rest items  The user won t see the inner-workings of it  because you ll won t have half-transparent headers       And here what happens in the  pushing out  phase     Hope it helped   Edit  Here is my actual implementation of getHeaderPositionForItem   method in the RecyclerView s adapter    Override public int getHeaderPositionForItem int itemPosition        int headerPosition   0      do           if  this isHeader itemPosition                 headerPosition   itemPosition              break                    itemPosition -  1        while  itemPosition  gt   0       return headerPosition      Slightly different implementation in Kotlin

User · Answer

You can check and take the implementation of the class StickyHeaderHelper in my FlexibleAdapter project  and adapt it to your use case   But  I suggest to use the library since it simplifies and reorganizes the way you usually implement the Adapters for RecyclerView  Don t reinvent the wheel   I would also say  don t use Decorators or deprecated libraries  as well as don t use libraries that do only 1 or 3 things  you will have to merge implementations of others libraries yourself

User · Answer

I ve made my own variation of Sevastyan s solution above  class HeaderItemDecoration recyclerView  RecyclerView  private val listener  StickyHeaderInterface    RecyclerView ItemDecoration      private val headerContainer   FrameLayout recyclerView context  private var stickyHeaderHeight  Int   0 private var currentHeader  View    null private var currentHeaderPosition   0  init       val layout   RelativeLayout recyclerView context      val params   recyclerView layoutParams     val parent   recyclerView parent as ViewGroup     val index   parent indexOfChild recyclerView      parent addView layout  index  params      parent removeView recyclerView      layout addView recyclerView  LayoutParams MATCH PARENT  LayoutParams MATCH PARENT      layout addView headerContainer  LayoutParams MATCH PARENT  LayoutParams WRAP CONTENT     override fun onDrawOver c  Canvas  parent  RecyclerView  state  RecyclerView State        super onDrawOver c  parent  state       val topChild   parent getChildAt 0     return      val topChildPosition   parent getChildAdapterPosition topChild      if  topChildPosition    RecyclerView NO POSITION            return            val currentHeader   getHeaderViewForItem topChildPosition  parent      fixLayoutSize parent  currentHeader      val contactPoint   currentHeader bottom     val childInContact   getChildInContact parent  contactPoint     return      val nextPosition   parent getChildAdapterPosition childInContact      if  listener isHeader nextPosition             moveHeader currentHeader  childInContact  topChildPosition  nextPosition          return            drawHeader currentHeader  topChildPosition     private fun getHeaderViewForItem itemPosition  Int  parent  RecyclerView   View       val headerPosition   listener getHeaderPositionForItem itemPosition      val layoutResId   listener getHeaderLayout headerPosition      val header   LayoutInflater from parent context  inflate layoutResId  parent  false      listener bindHeaderData header  headerPosition      return header    private fun drawHeader header  View  position  Int        headerContainer layoutParams height   stickyHeaderHeight     setCurrentHeader header  position     private fun moveHeader currentHead  View  nextHead  View  currentPos  Int  nextPos  Int        val marginTop   nextHead top - currentHead height     if  currentHeaderPosition    nextPos  amp  amp  currentPos    nextPos  setCurrentHeader currentHead  currentPos       val params   currentHeader  layoutParams as  MarginLayoutParams    return     params setMargins 0  marginTop  0  0      currentHeader  layoutParams   params      headerContainer layoutParams height   stickyHeaderHeight   marginTop    private fun setCurrentHeader header  View  position  Int        currentHeader   header     currentHeaderPosition   position     headerContainer removeAllViews       headerContainer addView currentHeader     private fun getChildInContact parent  RecyclerView  contactPoint  Int   View             0 until parent childCount               map   parent getChildAt it                 firstOrNull   it bottom  gt  contactPoint  amp  amp  it top  lt   contactPoint    private fun fixLayoutSize parent  ViewGroup  view  View         val widthSpec   View MeasureSpec makeMeasureSpec parent width  View MeasureSpec EXACTLY      val heightSpec   View MeasureSpec makeMeasureSpec parent height  View MeasureSpec UNSPECIFIED       val childWidthSpec   ViewGroup getChildMeasureSpec widthSpec              parent paddingLeft   parent paddingRight              view layoutParams width      val childHeightSpec   ViewGroup getChildMeasureSpec heightSpec              parent paddingTop   parent paddingBottom              view layoutParams height       view measure childWidthSpec  childHeightSpec       stickyHeaderHeight   view measuredHeight     view layout 0  0  view measuredWidth  stickyHeaderHeight     interface StickyHeaderInterface        fun getHeaderPositionForItem itemPosition  Int   Int      fun getHeaderLayout headerPosition  Int   Int      fun bindHeaderData header  View  headerPosition  Int       fun isHeader itemPosition  Int   Boolean           and here is implementation of StickyHeaderInterface  I did it directly in recycler adapter    override fun getHeaderPositionForItem itemPosition  Int   Int        itemPosition downTo 0           map   Pair isHeader it   it             firstOrNull   it first    second    RecyclerView NO POSITION  override fun getHeaderLayout headerPosition  Int   Int                     return something like R layout view header       or add conditions if you have different headers on different positions               override fun bindHeaderData header  View  headerPosition  Int        if  headerPosition    RecyclerView NO POSITION  header layoutParams height   0     else              here you get your header and can change some data on it               override fun isHeader itemPosition  Int   Boolean                    here have to be condition for checking - is item on this position header                So  in this case header is not just drawing on canvas  but view with selector or ripple  clicklistener  etc

User · Answer

Another solution  based on scroll listener  Initial conditions are the same as in Sevastyan answer  RecyclerView recyclerView  TextView tvTitle    sticky header view        onCreate  initialize  etc     public void bindList List lt Item gt  items      All data in adapter  Item - just interface for different item types     adapter   new YourAdapter items       recyclerView setAdapter adapter       StickyHeaderViewManager lt HeaderItem gt  stickyHeaderViewManager   new StickyHeaderViewManager lt  gt               tvTitle              recyclerView              HeaderItem class    HeaderItem - subclass of Item  used to detect headers in list             data - gt       bind function for sticky header view                 tvTitle setText data getTitle                         stickyHeaderViewManager attach items       Layout for ViewHolder and sticky header   item header xml       lt TextView xmlns android  http   schemas android com apk res android      android id    id tv title      android layout width  match parent      android layout height  wrap content   gt    Layout for RecyclerView   lt FrameLayout     android layout width  match parent      android layout height  match parent  gt        lt android support v7 widget RecyclerView         android id    id recycler view          android layout width  match parent          android layout height  match parent   gt        lt  --it can be any view  but order important  draw over recyclerView-- gt       lt include         layout   layout item header   gt    lt  FrameLayout gt    Class for HeaderItem   public class HeaderItem implements Item        private String title       public HeaderItem String title            this title   title             public String getTitle             return title             It s all use  The implementation of the adapter  ViewHolder and other things  is not interesting for us   public class StickyHeaderViewManager lt T gt          Nonnull     private View headerView        Nonnull     private RecyclerView recyclerView        Nonnull     private StickyHeaderViewWrapper lt T gt  viewWrapper        Nonnull     private Class lt T gt  headerDataClass       private List lt   gt  items       public StickyHeaderViewManager  Nonnull View headerView                                      Nonnull RecyclerView recyclerView                                      Nonnull Class lt T gt  headerDataClass                                      Nonnull StickyHeaderViewWrapper lt T gt  viewWrapper            this headerView   headerView          this viewWrapper   viewWrapper          this recyclerView   recyclerView          this headerDataClass   headerDataClass             public void attach  Nonnull List lt   gt  items            this items   items          if  ViewCompat isLaidOut headerView                 bindHeader recyclerView             else               headerView post    - gt  bindHeader recyclerView                       recyclerView addOnScrollListener new RecyclerView OnScrollListener                   Override             public void onScrolled RecyclerView recyclerView  int dx  int dy                    super onScrolled recyclerView  dx  dy                   bindHeader recyclerView                                        private void bindHeader RecyclerView recyclerView            if  items isEmpty                  headerView setVisibility View GONE               return            else               headerView setVisibility View VISIBLE                      View topView   recyclerView getChildAt 0           if  topView    null                return                    int topPosition   recyclerView getChildAdapterPosition topView           if   isValidPosition topPosition                 return                    if  topPosition    0  amp  amp  topView getTop      recyclerView getTop                  headerView setVisibility View GONE               return            else               headerView setVisibility View VISIBLE                      T stickyItem          Object firstItem   items get topPosition           if  headerDataClass isInstance firstItem                 stickyItem   headerDataClass cast firstItem               headerView setTranslationY 0             else               stickyItem   findNearestHeader topPosition               int secondPosition   topPosition   1              if  isValidPosition secondPosition                     Object secondItem   items get secondPosition                   if  headerDataClass isInstance secondItem                         View secondView   recyclerView getChildAt 1                       if  secondView    null                            moveViewFor secondView                                           else                       headerView setTranslationY 0                                                      if  stickyItem    null                viewWrapper bindView stickyItem                        private void moveViewFor View secondView            if  secondView getTop    lt   headerView getBottom                  headerView setTranslationY secondView getTop   - headerView getHeight               else               headerView setTranslationY 0                        private T findNearestHeader int position            for  int i   position  position  gt   0  i--                Object item   items get i               if  headerDataClass isInstance item                     return headerDataClass cast item                                   return null             private boolean isValidPosition int position            return   position    RecyclerView NO POSITION    position  gt   items size               Interface for bind header view   public interface StickyHeaderViewWrapper lt T gt         void bindView T data

User · Answer

Yo   This is how you do it if you want just one type of holder stick when it starts getting out of the screen  we are not caring about any sections   There is only one way without breaking the internal RecyclerView logic of recycling items and that is to inflate additional view on top of the recyclerView s header item and pass data into it  I ll let the code speak   import android graphics Canvas import android graphics Rect import android view LayoutInflater import android view View import android view ViewGroup import androidx annotation LayoutRes import androidx recyclerview widget RecyclerView  class StickyHeaderItemDecoration  LayoutRes private val headerId  Int  private val HEADER TYPE  Int    RecyclerView ItemDecoration      private lateinit var stickyHeaderView  View private lateinit var headerView  View  private var sticked   false     executes on each bind and sets the stickyHeaderView override fun getItemOffsets outRect  Rect  view  View  parent  RecyclerView  state  RecyclerView State        super getItemOffsets outRect  view  parent  state       val position   parent getChildAdapterPosition view       val adapter   parent adapter    return     val viewType   adapter getItemViewType position       if  viewType    HEADER TYPE            headerView   view          override fun onDrawOver c  Canvas  parent  RecyclerView  state  RecyclerView State        super onDrawOver c  parent  state      if    headerView isInitialized             if  headerView y  lt   0  amp  amp   sticked                stickyHeaderView   createHeaderView parent              fixLayoutSize parent  stickyHeaderView              sticked   true                    if  headerView y  gt  0  amp  amp  sticked                sticked   false                    if  sticked                drawStickedHeader c                     private fun createHeaderView parent  RecyclerView    LayoutInflater from parent context  inflate headerId  parent  false   private fun drawStickedHeader c  Canvas        c save       c translate 0f  Math max 0f  stickyHeaderView top toFloat   - stickyHeaderView height toFloat         headerView draw c      c restore      private fun fixLayoutSize parent  ViewGroup  view  View            Specs for parent  RecyclerView      val widthSpec   View MeasureSpec makeMeasureSpec parent width  View MeasureSpec EXACTLY      val heightSpec   View MeasureSpec makeMeasureSpec parent height  View MeasureSpec UNSPECIFIED          Specs for children  headers      val childWidthSpec   ViewGroup getChildMeasureSpec widthSpec  parent paddingLeft   parent paddingRight  view getLayoutParams   width      val childHeightSpec   ViewGroup getChildMeasureSpec heightSpec  parent paddingTop   parent paddingBottom  view getLayoutParams   height       view measure childWidthSpec  childHeightSpec       view layout 0  0  view measuredWidth  view measuredHeight         And then you just do this in your adapter   override fun onAttachedToRecyclerView recyclerView  RecyclerView        super onAttachedToRecyclerView recyclerView      recyclerView addItemDecoration StickyHeaderItemDecoration R layout item time filter  YOUR STICKY VIEW HOLDER TYPE       Where YOUR STICKY VIEW HOLDER TYPE is viewType of your what is supposed to be sticky holder

User · Answer

For those who may concern  Based on Sevastyan s answer  should you want to make it horizontal scroll  Simply change all getBottom   to getRight   and getTop   to getLeft

[android] How can I make sticky headers in RecyclerView? (Without external lib)

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