Android Recyclerview GridLayoutManager column spacing

Question

How do you set the column spacing with a RecyclerView using a GridLayoutManager   Setting the margin padding inside my layout has no effect

User · Answer

The following is the step-by-step simple solution if you want the equal spacing around items and equal item sizes.

ItemOffsetDecoration

public class ItemOffsetDecoration extends RecyclerView.ItemDecoration {

    private int mItemOffset;

    public ItemOffsetDecoration(int itemOffset) {
        mItemOffset = itemOffset;
    }

    public ItemOffsetDecoration(@NonNull Context context, @DimenRes int itemOffsetId) {
        this(context.getResources().getDimensionPixelSize(itemOffsetId));
    }

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

Implementation

In your source code, add ItemOffsetDecoration to your RecyclerView. Item offset value should be half size of the actual value you want to add as space between items.

mRecyclerView.setLayoutManager(new GridLayoutManager(context, NUM_COLUMNS);
ItemOffsetDecoration itemDecoration = new ItemOffsetDecoration(context, R.dimen.item_offset);
mRecyclerView.addItemDecoration(itemDecoration);

Also, set item offset value as padding for itsRecyclerView, and specify android:clipToPadding=false.

<android.support.v7.widget.RecyclerView
    android:id="@+id/recyclerview_grid"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:clipToPadding="false"
    android:padding="@dimen/item_offset"/>

User · Answer

yqritc s answer worked perfectly for me  I was using Kotlin however so here is the equivalent of that   class ItemOffsetDecoration   RecyclerView ItemDecoration            amount to add to padding     private val  itemOffset  Int      constructor itemOffset  Int             itemOffset   itemOffset            constructor  NonNull context  Context   DimenRes itemOffsetId  Int           itemOffset   context resources getDimensionPixelSize itemOffsetId                        Applies padding to all sides of the  Rect   which is the container for the view             override fun getItemOffsets outRect  Rect  view  View  parent  RecyclerView state  RecyclerView State            super getItemOffsets outRect  view  parent  state          outRect set  itemOffset   itemOffset   itemOffset   itemOffset            everything else is the same

User · Answer

The selected answer is almost perfect  but depending on the space  items width can be not equal   In my case it was critical   So i ve ended up with this code which increases space a little bit  so items are all the same width      class GridSpacingItemDecoration private val columnCount  Int   Px preferredSpace  Int  private val includeEdge  Boolean   RecyclerView ItemDecoration                     In this algorithm space should divide by 3 without remnant or width of items can have a difference        and we want them to be exactly the same             private val space   if  preferredSpace   3    0  preferredSpace else  preferredSpace    3 - preferredSpace   3        override fun getItemOffsets outRect  Rect  view  View  parent  RecyclerView  state  RecyclerView State             val position   parent getChildAdapterPosition view           if  includeEdge                 when                   position   columnCount    0 - gt                        outRect left   space                     outRect right   space   3                                   position   columnCount    columnCount - 1 - gt                        outRect right   space                     outRect left   space   3                                   else - gt                        outRect left   space   2   3                     outRect right   space   2   3                                              if  position  lt  columnCount                    outRect top   space                            outRect bottom   space            else                when                   position   columnCount    0 - gt  outRect right   space   2   3                 position   columnCount    columnCount - 1 - gt  outRect left   space   2   3                 else - gt                        outRect left   space   3                     outRect right   space   3                                              if  position  gt   columnCount                    outRect top   space

User · Answer

To made https   stackoverflow com a 29905000 1649371  above  solution work I had to modify the following methods  and all subsequent calls    SuppressWarnings  all   protected int getItemSpanSize RecyclerView parent  View view  int childIndex         RecyclerView LayoutManager mgr   parent getLayoutManager        if  mgr instanceof GridLayoutManager            return   GridLayoutManager  mgr  getSpanSizeLookup   getSpanSize childIndex         else if  mgr instanceof StaggeredGridLayoutManager            return   StaggeredGridLayoutManager LayoutParams  view getLayoutParams    isFullSpan     spanCount   1        else if  mgr instanceof LinearLayoutManager            return 1             return -1      SuppressWarnings  all   protected int getItemSpanIndex RecyclerView parent  View view  int childIndex         RecyclerView LayoutManager mgr   parent getLayoutManager        if  mgr instanceof GridLayoutManager            return   GridLayoutManager  mgr  getSpanSizeLookup   getSpanIndex childIndex  spanCount         else if  mgr instanceof StaggeredGridLayoutManager            return   StaggeredGridLayoutManager LayoutParams  view getLayoutParams    getSpanIndex          else if  mgr instanceof LinearLayoutManager            return 0             return -1

User · Answer

For StaggeredGridLayoutManager users  be careful  lots of answers here including the most voted one calculates the item column with below code   int column   position   spanCount   which assumes that the 1st 3rd 5th    items are always located at left side and 2nd 4th 6th    items are always located at right side  Is this assumption always true  No   Let s say your 1st item is 100dp high and 2nd is only 50dp  guess where is your 3rd item located  left or right

User · Answer

There is only one easy solution  that you can remember and implement wherever needed  No bugs  no crazy calculations  Put margin to the card   item layout and put the same size as padding to the RecyclerView   item layout xml   lt CardView     android layout width  match parent      android layout height  wrap content      android margin  10dp  gt    activity layout xml   lt RecyclerView     android layout width  match parent      android layout height  wrap content      android padding  10dp   gt    UPDATE

User · Answer

Here is my modification of SpacesItemDecoration which can take numOfColums and space equally on top  bottom  left and right       public class SpacesItemDecoration extends RecyclerView ItemDecoration       private int space      private int mNumCol       public SpacesItemDecoration int space  int numCol            this space   space          this mNumCol numCol              Override     public void getItemOffsets Rect outRect  View view                                 RecyclerView parent  RecyclerView State state               outRect right   space          outRect bottom   space            outRect left   space             Log d  ttt    item position    parent getChildLayoutPosition view            int position parent getChildLayoutPosition view            if mNumCol lt  2                if  position    0                    outRect left   space                  outRect right   space   2                else                   if   position   mNumCol     0                        outRect left   space   2                      outRect right   space                    else                       outRect left   space                      outRect right   space   2                                           else              if  position    0                    outRect left   space                  outRect right   space   2                else                   if   position   mNumCol     0                        outRect left   space                      outRect right   space 2                    else if  position   mNumCol      mNumCol-1                        outRect left   space 2                      outRect right   space                   else                      outRect left space 2                      outRect right space 2                                                      if position lt mNumCol               outRect top space           else              outRect top 0                       Add top margin only for the first item to avoid double space between items                    if  parent getChildLayoutPosition view     0                else               outRect top   0                        and use below code on your logic    recyclerView addItemDecoration new SpacesItemDecoration spacingInPixels  numCol

User · Answer

There is a very simple and yet flexible solution for this problem using only XML which works on every LayoutManager   Assume you want an equal spacing of X  8dp for example     Wrap your CardView item in another Layout Give the outer Layout a padding of X 2  4dp  Make the outer Layout background transparent         lt LinearLayout xmlns android  http   schemas android com apk res android      android layout width  200dp      android layout height  200dp      android background   android color transparent      android padding  4dip  gt        lt android support v7 widget CardView         android layout width  match parent          android layout height  match parent  gt       lt  android support v7 widget CardView gt    lt  LinearLayout gt     Give your RecyclerView a padding of X 2  4dp          lt android support v7 widget RecyclerView     android layout width  match parent      android layout height  match parent      android padding  4dp    gt    and thats it  You have perfect spacing of X  8dp

User · Answer

If you are using Header with GridLayoutManager use this code written in kotlin for spacing between the grids    inner class SpacesItemDecoration itemSpace  Int    RecyclerView ItemDecoration         var space  Int   itemSpace      override fun getItemOffsets outRect  Rect   view  View   parent  RecyclerView   state  RecyclerView State             super getItemOffsets outRect  view  parent  state          val position   parent   getChildAdapterPosition view          val viewType   parent adapter getItemViewType position           check to not to set any margin to header item          if  viewType    GridViewAdapter TYPE HEADER                outRect   top   0             outRect left   0             outRect right   0             outRect bottom   0           else               outRect   left   space             outRect right   space             outRect bottom   space              if  parent getChildLayoutPosition view     0                    outRect top   space               else                   outRect top   0                                       And pass ItemDecoration to recyclerview as   mIssueGridView addItemDecoration SpacesItemDecoration 10

User · Answer

public class GridSpacingItemDecoration extends RecyclerView ItemDecoration        private int spanCount      private int spacing      private boolean includeEdge       public GridSpacingItemDecoration int spanCount  int spacing  boolean includeEdge            this spanCount   spanCount          this spacing   spacing          this includeEdge   includeEdge              Override     public void getItemOffsets Rect outRect  View view  RecyclerView parent  RecyclerView State state            StaggeredGridLayoutManager LayoutParams params    StaggeredGridLayoutManager LayoutParams  view getLayoutParams            int column   params getSpanIndex             if  includeEdge                outRect left   spacing - column   spacing   spanCount     spacing - column     1f   spanCount    spacing              outRect right    column   1    spacing   spanCount      column   1      1f   spanCount    spacing               if  position  lt  spanCount       top edge                 outRect top   spacing                            outRect bottom   spacing     item bottom           else               outRect left   column   spacing   spanCount     column     1f   spanCount    spacing              outRect right   spacing -  column   1    spacing   spanCount     spacing -  column   1      1f      spanCount    spacing              if  position  gt   spanCount                    outRect top   spacing     item top                                   A little bit different from edwardaa s answer  the difference is how the column is determined  because in cases such as items with various heights  the column can not be determined by simply   spanCount

User · Answer

Following code works well  and each column has same width   public class GridSpacingItemDecoration extends RecyclerView ItemDecoration        private int spanCount      private int spacing      private boolean includeEdge       public GridSpacingItemDecoration int spanCount  int spacing  boolean includeEdge            this spanCount   spanCount          this spacing   spacing          this includeEdge   includeEdge              Override     public void getItemOffsets Rect outRect  View view  RecyclerView parent  RecyclerView State state            int position   parent getChildAdapterPosition view      item position         int column   position   spanCount     item column          if  includeEdge                outRect left   spacing - column   spacing   spanCount     spacing - column     1f   spanCount    spacing              outRect right    column   1    spacing   spanCount      column   1      1f   spanCount    spacing               if  position  lt  spanCount       top edge                 outRect top   spacing                            outRect bottom   spacing     item bottom           else               outRect left   column   spacing   spanCount     column     1f   spanCount    spacing              outRect right   spacing -  column   1    spacing   spanCount     spacing -  column   1      1f      spanCount    spacing              if  position  gt   spanCount                    outRect top   spacing     item top                                   Usage  1  no edge    int spanCount   3     3 columns int spacing   50     50px boolean includeEdge   false  recyclerView addItemDecoration new GridSpacingItemDecoration spanCount  spacing  includeEdge      2  with edge    int spanCount   3     3 columns int spacing   50     50px boolean includeEdge   true  recyclerView addItemDecoration new GridSpacingItemDecoration spanCount  spacing  includeEdge

User · Answer

Answers above have clarified ways to set margin handling GridLayoutManager and LinearLayoutManager   But for StaggeredGridLayoutManager  Pirdad Sakhizada s answer says   It might not work very well with StaggeredGridLayoutManager   It should be the problem about IndexOfSpan   You can get it by this way   private static class MyItemDecoration extends RecyclerView ItemDecoration        Override     public void getItemOffsets Rect outRect  View view  RecyclerView parent  RecyclerView State state            super getItemOffsets outRect  view  parent  state           int index     StaggeredGridLayoutManager LayoutParams  view getLayoutParams    getSpanIndex

User · Answer

Here is a solution that doesn t require  spanCount   number of columns  I use it because I use GridAutofitLayoutManager calculates the number of columns according to the required cell size    beware that this will only work on GridLayoutManager   public class GridSpacesItemDecoration extends RecyclerView ItemDecoration       private final boolean includeEdge      private int spacing        public GridSpacesItemDecoration int spacing  boolean includeEdge            this spacing   spacing          this includeEdge   includeEdge              Override     public void getItemOffsets Rect outRect  View view  RecyclerView parent  RecyclerView State state            if  parent getLayoutManager   instanceof GridLayoutManager                GridLayoutManager layoutManager    GridLayoutManager parent getLayoutManager                int spanCount   layoutManager getSpanCount                int position   parent getChildAdapterPosition view      item position             int column   position   spanCount     item column              if  includeEdge                    outRect left   spacing - column   spacing   spanCount     spacing - column     1f   spanCount    spacing                  outRect right    column   1    spacing   spanCount      column   1      1f   spanCount    spacing                   if  position  lt  spanCount       top edge                     outRect top   spacing                                    outRect bottom   spacing     item bottom               else                   outRect left   column   spacing   spanCount     column     1f   spanCount    spacing                  outRect right   spacing -  column   1    spacing   spanCount     spacing -  column   1      1f      spanCount    spacing                  if  position  gt   spanCount                        outRect top   spacing     item top                                                       Here is the GridAutofitLayoutManager is anyone is interested   public class GridAutofitLayoutManager extends GridLayoutManager       private int mColumnWidth      private boolean mColumnWidthChanged   true       public GridAutofitLayoutManager Context context  int columnWidth                   Initially set spanCount to 1  will be changed automatically later             super context  1           setColumnWidth checkedColumnWidth context  columnWidth               public GridAutofitLayoutManager Context context int unit  int columnWidth                   Initially set spanCount to 1  will be changed automatically later             super context  1           int pixColumnWidth    int  TypedValue applyDimension unit  columnWidth  context getResources   getDisplayMetrics             setColumnWidth checkedColumnWidth context  pixColumnWidth               public GridAutofitLayoutManager Context context  int columnWidth  int orientation  boolean reverseLayout                   Initially set spanCount to 1  will be changed automatically later             super context  1  orientation  reverseLayout           setColumnWidth checkedColumnWidth context  columnWidth               private int checkedColumnWidth Context context  int columnWidth                if  columnWidth  lt   0                           Set default columnWidth value  48dp here   It is better to move this constant             to static constant on top  but we need context to convert it to dp  so can t really             do so                 columnWidth    int  TypedValue applyDimension TypedValue COMPLEX UNIT DIP  48                      context getResources   getDisplayMetrics                       return columnWidth             public void setColumnWidth int newColumnWidth                if  newColumnWidth  gt  0  amp  amp  newColumnWidth    mColumnWidth                        mColumnWidth   newColumnWidth              mColumnWidthChanged   true                        Override     public void onLayoutChildren RecyclerView Recycler recycler  RecyclerView State state                int width   getWidth            int height   getHeight            if  mColumnWidthChanged  amp  amp  mColumnWidth  gt  0  amp  amp  width  gt  0  amp  amp  height  gt  0                        int totalSpace              if  getOrientation      VERTICAL                                totalSpace   width - getPaddingRight   - getPaddingLeft                              else                               totalSpace   height - getPaddingTop   - getPaddingBottom                              int spanCount   Math max 1  totalSpace   mColumnWidth               setSpanCount spanCount                mColumnWidthChanged   false                    super onLayoutChildren recycler  state             Finally   mDevicePhotosView setLayoutManager new GridAutofitLayoutManager getContext    getResources   getDimensionPixelSize R dimen item size     mDevicePhotosView addItemDecoration new GridSpacesItemDecoration Util dpToPx getContext    2  true

User · Answer

If you have a toggle switch that toggles between list to grid  don t forget to call recyclerView removeItemDecoration   before setting any new Item decoration  If not then the new calculations for the spacing would be incorrect     Something like this           recyclerView removeItemDecoration gridItemDecorator          recyclerView removeItemDecoration listItemDecorator          if  showAsList               recyclerView layoutManager   LinearLayoutManager this  LinearLayoutManager VERTICAL  false              recyclerView addItemDecoration listItemDecorator                    else              recyclerView layoutManager   GridLayoutManager this  spanCount              recyclerView addItemDecoration gridItemDecorator

User · Answer

The following code will handle StaggeredGridLayoutManager  GridLayoutManager  and LinearLayoutManager   public class SpacesItemDecoration extends RecyclerView ItemDecoration        private int halfSpace       public SpacesItemDecoration int space            this halfSpace   space   2              Override     public void getItemOffsets Rect outRect  View view  RecyclerView parent  RecyclerView State state             if  parent getPaddingLeft      halfSpace                parent setPadding halfSpace  halfSpace  halfSpace  halfSpace               parent setClipToPadding false                      outRect top   halfSpace          outRect bottom   halfSpace          outRect left   halfSpace          outRect right   halfSpace            Then use it  mRecyclerView addItemDecoration new SpacesItemDecoration mMargin

User · Answer

for anyone like me  who want the best answer but in kotlin  here it is  class GridItemDecoration      val spacing  Int      private val spanCount  Int      private val includeEdge  Boolean         RecyclerView ItemDecoration                     Applies padding to all sides of the  Rect   which is the container for the view             override fun getItemOffsets          outRect  Rect          view  View          parent  RecyclerView          state  RecyclerView State                 val position   parent getChildAdapterPosition view     item position         val column   position   spanCount    item column         if  includeEdge                outRect left                   spacing - column   spacing   spanCount    spacing - column     1f   spanCount    spacing              outRect right                    column   1    spacing   spanCount     column   1      1f   spanCount    spacing              if  position  lt  spanCount       top edge                 outRect top   spacing                           outRect bottom   spacing    item bottom           else               outRect left                   column   spacing   spanCount    column     1f   spanCount    spacing              outRect right                   spacing -  column   1    spacing   spanCount    spacing -  column   1      1f      spanCount    spacing              if  position  gt   spanCount                    outRect top   spacing    item top                                  plus if you want to get the number from dimens xml and then convert it to raw pixel you can do it easily using getDimensionPixelOffset easily like this  recyclerView addItemDecoration                  GridItemDecoration                      resources getDimensionPixelOffset R dimen h1                       3                      true

User · Answer

If you want to FIXED the size of your RecyclerView item in all devices  You can do like this  public class GridSpacingItemDecoration extends RecyclerView ItemDecoration        private int mSpanCount      private float mItemSize       public GridSpacingItemDecoration int spanCount  int itemSize            this mSpanCount   spanCount          mItemSize   itemSize              Override     public void getItemOffsets final Rect outRect  final View view  RecyclerView parent              RecyclerView State state            final int position   parent getChildLayoutPosition view           final int column   position   mSpanCount          final int parentWidth   parent getWidth            int spacing    int   parentWidth -  mItemSize   mSpanCount      mSpanCount   1           outRect left   spacing - column   spacing   mSpanCount          outRect right    column   1    spacing   mSpanCount           if  position  lt  mSpanCount                outRect top   spacing                    outRect bottom   spacing            recyclerview item xml   lt LinearLayout     xmlns android  http   schemas android com apk res android      android layout width   dimen recycler view item width                gt           lt  LinearLayout gt    dimens xml    lt dimen name  recycler view item width  gt 60dp lt  dimen gt    Activity  int numberOfColumns   3  mRecyclerView setLayoutManager new GridLayoutManager this  numberOfColumns    mRecyclerView setAdapter       mRecyclerView addItemDecoration new GridSpacingItemDecoration 3          getResources   getDimensionPixelSize R dimen recycler view item width

User · Answer

This is what finally ended up working for me         binding rows addItemDecoration object  RecyclerView ItemDecoration                val px   resources getDimensionPixelSize R dimen grid spacing              val spanCount   2             override fun getItemOffsets outRect  Rect  view  View  parent  RecyclerView  state  RecyclerView State                    val index   parent getChildLayoutPosition view                  val isLeft    index   spanCount    0                  outRect set                      if  isLeft  px else px 2                      0                      if  isLeft  px 2 else px                      px                                             Since there are only 2 columns for me  val spanCount   2   I can do with just isLeft  If there were  gt  2 columns  then I d need a isMiddle as well  and the value for both sides would be px 2  I wish there was a way to get the app spanCount from directly from the RecyclerView  but I don t believe there is

User · Answer

This Link worked for me all situations you may try this

User · Answer

The answers on for this question seem more complex than they should be  Here s my take on this   Let s say you want 1dp spacing between grid items  Do the following    Add a padding of 0 5dp to each item Add a padding of -0 5dp to the RecycleView That s it

User · Answer

I ended up doing it like that for my RecyclerView with GridLayoutManager and HeaderView   In the code below I set a 4dp space between every item 2dp around every single item and 2dp padding around the whole recyclerview     layout xml   lt android support v7 widget RecyclerView     android id    id recycleview      android layout width  match parent      android layout height  match parent      android padding  2dp    gt    fragment activity  GridLayoutManager manager   new GridLayoutManager getContext    3   recyclerView setLayoutManager manager   int spacingInPixels   Utils dpToPx 2   recyclerView addItemDecoration new SpacesItemDecoration spacingInPixels      SpaceItemDecoration java  public class SpacesItemDecoration extends RecyclerView ItemDecoration        private int mSpacing       public SpacesItemDecoration int spacing            mSpacing   spacing              Override     public void getItemOffsets Rect outRect  View view  RecyclerView recyclerView  RecyclerView State state            outRect left   mSpacing          outRect top   mSpacing          outRect right   mSpacing          outRect bottom   mSpacing            Utils java  public static int dpToPx final float dp        return Math round dp    Resources getSystem   getDisplayMetrics   xdpi   DisplayMetrics DENSITY DEFAULT

User · Answer

RecyclerViews support the concept of ItemDecoration  special offsets and drawing around each element  As seen in this answer  you can use   public class SpacesItemDecoration extends RecyclerView ItemDecoration     private int space     public SpacesItemDecoration int space        this space   space          Override   public void getItemOffsets Rect outRect  View view         RecyclerView parent  RecyclerView State state        outRect left   space      outRect right   space      outRect bottom   space          Add top margin only for the first item to avoid double space between items     if  parent getChildLayoutPosition view     0            outRect top   space        else           outRect top   0                Then add it via  mRecyclerView    RecyclerView  rootView findViewById R id my recycler view   int spacingInPixels   getResources   getDimensionPixelSize R dimen spacing   mRecyclerView addItemDecoration new SpacesItemDecoration spacingInPixels

User · Answer

When using CardView for children problem with spaces between items can by solved by setting app cardUseCompatPadding to true   For bigger margins enlarge item elevation  CardElevation is optional  use default value     lt androidx cardview widget CardView     xmlns app  http   schemas android com apk res-auto      app cardUseCompatPadding  true      app cardElevation  2dp  gt

User · Answer

class VerticalGridSpacingDecoration private val spacing  Int    RecyclerView ItemDecoration        override fun getItemOffsets      outRect  Rect      view  View      parent  RecyclerView      state  State           val layoutManager   parent layoutManager as  GridLayoutManager     if  layoutManager    null    layoutManager orientation    VERTICAL          return super getItemOffsets outRect  view  parent  state             val spanCount   layoutManager spanCount     val position   parent getChildAdapterPosition view      val column   position   spanCount     with outRect          left   if  column    0  0 else spacing   2       right   if  column    spanCount dec    0 else spacing   2       top   if  position  lt  spanCount  0 else spacing

User · Answer

Try this  It ll take care of equal spacing all around  Works both with List  Grid  and StaggeredGrid   Edited  The updated code should handle most of the corner cases with spans  orientation  etc  Note that if using setSpanSizeLookup   with GridLayoutManager  setting setSpanIndexCacheEnabled   is recommended for performance reasons    Note  it seems that with StaggeredGrid  there s seems to be a bug where the index of the children gets wacky and hard to track so the code below might not work very well with StaggeredGridLayoutManager   public class ListSpacingDecoration extends RecyclerView ItemDecoration      private static final int VERTICAL   OrientationHelper VERTICAL     private int orientation   -1    private int spanCount   -1    private int spacing    private int halfSpacing      public ListSpacingDecoration Context context   DimenRes int spacingDimen         spacing   context getResources   getDimensionPixelSize spacingDimen       halfSpacing   spacing   2         public ListSpacingDecoration int spacingPx         spacing   spacingPx      halfSpacing   spacing   2          Override   public void getItemOffsets Rect outRect  View view  RecyclerView parent  RecyclerView State state         super getItemOffsets outRect  view  parent  state        if  orientation    -1            orientation   getOrientation parent              if  spanCount    -1            spanCount   getTotalSpan parent              int childCount   parent getLayoutManager   getItemCount        int childIndex   parent getChildAdapterPosition view        int itemSpanSize   getItemSpanSize parent  childIndex       int spanIndex   getItemSpanIndex parent  childIndex           INVALID SPAN        if  spanCount  lt  1  return       setSpacings outRect  parent  childCount  childIndex  itemSpanSize  spanIndex          protected void setSpacings Rect outRect  RecyclerView parent  int childCount  int childIndex  int itemSpanSize  int spanIndex         outRect top   halfSpacing      outRect bottom   halfSpacing      outRect left   halfSpacing      outRect right   halfSpacing       if  isTopEdge parent  childCount  childIndex  itemSpanSize  spanIndex             outRect top   spacing             if  isLeftEdge parent  childCount  childIndex  itemSpanSize  spanIndex             outRect left   spacing             if  isRightEdge parent  childCount  childIndex  itemSpanSize  spanIndex             outRect right   spacing             if  isBottomEdge parent  childCount  childIndex  itemSpanSize  spanIndex             outRect bottom   spacing                SuppressWarnings  all     protected int getTotalSpan RecyclerView parent         RecyclerView LayoutManager mgr   parent getLayoutManager        if  mgr instanceof GridLayoutManager            return   GridLayoutManager  mgr  getSpanCount          else if  mgr instanceof StaggeredGridLayoutManager            return   StaggeredGridLayoutManager  mgr  getSpanCount          else if  mgr instanceof LinearLayoutManager            return 1             return -1          SuppressWarnings  all     protected int getItemSpanSize RecyclerView parent  int childIndex         RecyclerView LayoutManager mgr   parent getLayoutManager        if  mgr instanceof GridLayoutManager            return   GridLayoutManager  mgr  getSpanSizeLookup   getSpanSize childIndex         else if  mgr instanceof StaggeredGridLayoutManager            return 1        else if  mgr instanceof LinearLayoutManager            return 1             return -1          SuppressWarnings  all     protected int getItemSpanIndex RecyclerView parent  int childIndex         RecyclerView LayoutManager mgr   parent getLayoutManager        if  mgr instanceof GridLayoutManager            return   GridLayoutManager  mgr  getSpanSizeLookup   getSpanIndex childIndex  spanCount         else if  mgr instanceof StaggeredGridLayoutManager            return childIndex   spanCount        else if  mgr instanceof LinearLayoutManager            return 0             return -1          SuppressWarnings  all     protected int getOrientation RecyclerView parent         RecyclerView LayoutManager mgr   parent getLayoutManager        if  mgr instanceof LinearLayoutManager            return   LinearLayoutManager  mgr  getOrientation          else if  mgr instanceof GridLayoutManager            return   GridLayoutManager  mgr  getOrientation          else if  mgr instanceof StaggeredGridLayoutManager            return   StaggeredGridLayoutManager  mgr  getOrientation               return VERTICAL         protected boolean isLeftEdge RecyclerView parent  int childCount  int childIndex  int itemSpanSize  int spanIndex         if  orientation    VERTICAL             return spanIndex    0         else            return  childIndex    0     isFirstItemEdgeValid  childIndex  lt  spanCount   parent  childIndex                protected boolean isRightEdge RecyclerView parent  int childCount  int childIndex  int itemSpanSize  int spanIndex         if  orientation    VERTICAL             return  spanIndex   itemSpanSize     spanCount         else            return isLastItemEdgeValid  childIndex  gt   childCount - spanCount   parent  childCount  childIndex  spanIndex                protected boolean isTopEdge RecyclerView parent  int childCount  int childIndex  int itemSpanSize  int spanIndex         if  orientation    VERTICAL             return  childIndex    0     isFirstItemEdgeValid  childIndex  lt  spanCount   parent  childIndex          else            return spanIndex    0               protected boolean isBottomEdge RecyclerView parent  int childCount  int childIndex  int itemSpanSize  int spanIndex         if  orientation    VERTICAL             return isLastItemEdgeValid  childIndex  gt   childCount - spanCount   parent  childCount  childIndex  spanIndex          else            return  spanIndex   itemSpanSize     spanCount               protected boolean isFirstItemEdgeValid boolean isOneOfFirstItems  RecyclerView parent  int childIndex         int totalSpanArea   0      if  isOneOfFirstItems            for  int i   childIndex  i  gt   0  i--                totalSpanArea   totalSpanArea   getItemSpanSize parent  i                        return isOneOfFirstItems  amp  amp  totalSpanArea  lt   spanCount         protected boolean isLastItemEdgeValid boolean isOneOfLastItems  RecyclerView parent  int childCount  int childIndex  int spanIndex         int totalSpanRemaining   0      if  isOneOfLastItems            for  int i   childIndex  i  lt  childCount  i                  totalSpanRemaining   totalSpanRemaining   getItemSpanSize parent  i                        return isOneOfLastItems  amp  amp   totalSpanRemaining  lt   spanCount - spanIndex           Hope it helps

User · Answer

Copied  edwardaa provided code and I make it perfect to support RTL   public class GridSpacingItemDecoration extends RecyclerView ItemDecoration       private int spanCount      private int spacing      private boolean includeEdge      private int headerNum      private boolean isRtl   TextUtilsCompat getLayoutDirectionFromLocale Locale getDefault       ViewCompat LAYOUT DIRECTION RTL       public GridSpacingItemDecoration int spanCount  int spacing  boolean includeEdge  int headerNum            this spanCount   spanCount          this spacing   spacing          this includeEdge   includeEdge          this headerNum   headerNum              Override     public void getItemOffsets Rect outRect  View view  RecyclerView parent  RecyclerView State state            int position   parent getChildAdapterPosition view  - headerNum     item position         if  position  gt   0                int column   position   spanCount     item column             if isRtl                    column   spanCount - 1 - column                            if  includeEdge                    outRect left   spacing - column   spacing   spanCount     spacing - column     1f   spanCount    spacing                  outRect right    column   1    spacing   spanCount      column   1      1f   spanCount    spacing                   if  position  lt  spanCount       top edge                     outRect top   spacing                                    outRect bottom   spacing     item bottom               else                   outRect left   column   spacing   spanCount     column     1f   spanCount    spacing                  outRect right   spacing -  column   1    spacing   spanCount     spacing -  column   1      1f      spanCount    spacing                  if  position  gt   spanCount                        outRect top   spacing     item top                                           else               outRect left   0              outRect right   0              outRect top   0              outRect bottom   0

User · Answer

A Kotlin version I made based on the great answer by edwardaa  class RecyclerItemDecoration private val spanCount  Int  private val spacing  Int    RecyclerView ItemDecoration        override fun getItemOffsets outRect  Rect  view  View  parent  RecyclerView  state  RecyclerView State         val spacing   Math round spacing   parent context resources displayMetrics density      val position   parent getChildAdapterPosition view      val column   position   spanCount      outRect left   spacing - column   spacing   spanCount     outRect right    column   1    spacing   spanCount      outRect top   if  position  lt  spanCount  spacing else 0     outRect bottom   spacing

User · Answer

This will work for RecyclerView with header as well   public class GridSpacingItemDecoration extends RecyclerView ItemDecoration        private int spanCount      private int spacing      private boolean includeEdge      private int headerNum       public GridSpacingItemDecoration int spanCount  int spacing  boolean includeEdge  int headerNum            this spanCount   spanCount          this spacing   spacing          this includeEdge   includeEdge          this headerNum   headerNum              Override     public void getItemOffsets Rect outRect  View view  RecyclerView parent  RecyclerView State state            int position   parent getChildAdapterPosition view  - headerNum     item position          if  position  gt   0                int column   position   spanCount     item column              if  includeEdge                    outRect left   spacing - column   spacing   spanCount     spacing - column     1f   spanCount    spacing                  outRect right    column   1    spacing   spanCount      column   1      1f   spanCount    spacing                   if  position  lt  spanCount       top edge                     outRect top   spacing                                    outRect bottom   spacing     item bottom               else                   outRect left   column   spacing   spanCount     column     1f   spanCount    spacing                  outRect right   spacing -  column   1    spacing   spanCount     spacing -  column   1      1f      spanCount    spacing                  if  position  gt   spanCount                        outRect top   spacing     item top                                           else               outRect left   0              outRect right   0              outRect top   0              outRect bottom   0

User · Answer

For those who have problems with staggeredLayoutManager  like https   imgur com XVutH5u   recyclerView s methods   getChildAdapterPosition view  getChildLayoutPosition view    sometimes return -1 as index so we might face troubles setting itemDecor  My solution is to override deprecated ItemDecoration s method   public void getItemOffsets Rect outRect  int itemPosition  RecyclerView parent    instead of the newbie   public void getItemOffsets Rect outRect  View view  RecyclerView parent  State state    like this   recyclerView addItemDecoration new RecyclerView ItemDecoration                  Override             public void getItemOffsets Rect outRect  int itemPosition  RecyclerView parent                    TheAdapter VH vh    TheAdapter VH  recyclerView findViewHolderForAdapterPosition itemPosition                   View itemView   vh itemView       itemView is the base view of viewHolder                   or instead of the 2 lines above maybe it s possible to use  View itemView   layoutManager findViewByPosition itemPosition       NOT TESTED                  StaggeredGridLayoutManager LayoutParams itemLayoutParams    StaggeredGridLayoutManager LayoutParams  itemView getLayoutParams                     int spanIndex   itemLayoutParams getSpanIndex                     if  spanIndex    0                                          else                                                     Seems to work for me so far

User · Answer

thanks edwardaa s answer https   stackoverflow com a 30701422 2227031  Another point to note is that   if total spacing and total itemWidth are not equal to the screen width  you also need to adjust itemWidth  for example  on adapter onBindViewHolder method  Utils init  mActivity   int width   0  if  includeEdge        width   ScreenUtils getScreenWidth   - spacing    spanCount   1     else       width   ScreenUtils getScreenWidth   - spacing    spanCount - 1     int itemWidth   width   spanCount   ConstraintLayout LayoutParams layoutParams    ConstraintLayout LayoutParams  holder imageViewAvatar getLayoutParams       suppose the width and height are the same layoutParams width   itemWidth  layoutParams height   itemWidth  holder imageViewAvatar setLayoutParams layoutParams

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If you ve scrolled far enough to reach this answer  I wrote a library for equal spacing which supports Vertical Horizontal  LTR RTL  LinearLayout GridLayout manager and Edge inclusion  Its basically a single file  so you can copy paste that file into your code   I tried to support StaggeredGridLayout but span index returned by this layout is not reliable  I would be glad to hear any suggestion for that

[android] Android Recyclerview GridLayoutManager column spacing

ItemOffsetDecoration

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