RecyclerView - Get view at particular position

Question

I have an activity with a RecyclerView and an ImageView  I am using the RecyclerView to show a list of images horizontally  When I click on an image in the RecyclerView the ImageView in the activity should show a bigger picture of the image  So far everything works fine   Now there are two more ImageButtons in the activity  imageButton left and imageButton right  When I click on imageButton left  the image in the ImageView should turn left and also  the thumbnail in the RecyclerView should reflect this change  Similar is the case with imageButton right   I am able to rotate the ImageView  But  how can I rotate the thumbnail in the RecyclerView  How can I get the ViewHolder s ImageView    Code   Activity XML    lt  xml version  1 0  encoding  utf-8   gt   lt 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  match parent      android orientation  vertical  gt        lt android support v7 widget RecyclerView         android id    id recyclerview          android layout width  match parent          android layout height  wrap content          android layout margin  10dp    gt         lt LinearLayout         android layout width  match parent          android layout height  wrap content          android layout margin  10dp          android orientation  vertical  gt            lt ImageView             android id    id original image              android layout width  200dp              android layout height  200dp              android scaleType  fitXY              android src   drawable image not available 2    gt            lt LinearLayout             android layout width  match parent              android layout height  wrap content              android layout marginTop  10dp              android gravity  center horizontal              android orientation  horizontal  gt                 lt ImageButton                 android id    id imageButton left                  android layout width  wrap content                  android layout height  wrap content                  android layout marginRight  20dp                  android background   drawable rotate left icon    gt                lt ImageButton                 android id    id imageButton right                  android layout width  wrap content                  android layout height  wrap content                  android background   drawable rotate right icon    gt            lt  LinearLayout gt       lt  LinearLayout gt   lt  LinearLayout gt    My Activity Code   public class SecondActivity extends AppCompatActivity implements IRecyclerViewClickListener         RecyclerView mRecyclerView      LinearLayoutManager mLayoutManager      RecyclerViewAdapter mRecyclerViewAdapter      List lt String gt  urls   new ArrayList lt String gt         ImageView mOriginalImageView      ImageButton mLeftRotate  mRightRotate        Override     protected void onCreate Bundle savedInstanceState            super onCreate savedInstanceState           setContentView R layout activity second           urls clear             mRecyclerView    RecyclerView  findViewById R id recyclerview           mLayoutManager   new LinearLayoutManager this  android support v7 widget LinearLayoutManager HORIZONTAL  false           mLayoutManager setOrientation android support v7 widget LinearLayoutManager HORIZONTAL           mRecyclerView setLayoutManager mLayoutManager           mRecyclerViewAdapter   new RecyclerViewAdapter this  urls           mRecyclerView setAdapter mRecyclerViewAdapter            mOriginalImageView    ImageView  findViewById R id original image           mLeftRotate    ImageButton  findViewById R id imageButton left           mLeftRotate setOnClickListener new View OnClickListener                  Override             public void onClick View v                    mOriginalImageView setRotation mOriginalImageView getRotation   - 90                                       mRightRotate    ImageButton  findViewById R id imageButton right           mRightRotate setOnClickListener new View OnClickListener                  Override             public void onClick View v                    mOriginalImageView setRotation mOriginalImageView getRotation     90                                      Intent intent   getIntent            if  intent    null                 String portfolio   intent getStringExtra  portfolio                 try                    JSONArray jsonArray   new JSONArray portfolio                    for  int i   0  i  lt  jsonArray length    i                           JSONObject jsonObject   jsonArray getJSONObject i                        String url   jsonObject getString  url                        urls add url                                      Log d Const DEBUG   URLs      urls toString                      mRecyclerViewAdapter notifyDataSetChanged                   catch  Exception e                    e printStackTrace                                           Override     public void onItemClick int position            Picasso with this  load urls get position   into mOriginalImageView             My Custom Adapter for RecyclerView   public class RecyclerViewAdapter extends RecyclerView Adapter lt RecyclerViewAdapter ViewHolder gt         Context context      List lt String gt  mUrls   new ArrayList lt String gt          IRecyclerViewClickListener mIRecyclerViewClickListener       public int position       public int getPosition             return position             public void setPosition int position            this position   position               public RecyclerViewAdapter Context context  List lt String gt  urls            this context   context          this mUrls clear            this mUrls   urls           Log d Const DEBUG   Urls Size      urls size             Log d Const DEBUG  urls toString              if  context instanceof IRecyclerViewClickListener              mIRecyclerViewClickListener    IRecyclerViewClickListener  context          else             Log d Const DEBUG   Implement IRecyclerViewClickListener in Activity                Override     public ViewHolder onCreateViewHolder ViewGroup parent  int viewType            View view   LayoutInflater from context  inflate R layout item horizontal recyclerview  parent  false           ViewHolder holder   new ViewHolder view           return holder              Override     public void onBindViewHolder ViewHolder holder  int position            Picasso with context  load mUrls get position   into holder mImageView               Override     public int getItemCount             return mUrls size                public void rotateThumbnail                  public class ViewHolder extends RecyclerView ViewHolder implements View OnClickListener            public ImageView mImageView          public View v           public ViewHolder View v                super v               v setTag getAdapterPosition                 v setOnClickListener this               this mImageView    ImageView  v findViewById R id image                       Override         public void onClick View v                this v   v              mIRecyclerViewClickListener onItemClick getAdapterPosition

User · Accepted Answer

I suppose you are using a LinearLayoutManager to show the list  It has a nice method called findViewByPosition that  Finds the view which represents the given adapter position   All you need is the adapter position of the item you are interested in  edit  as noted by Paul Woitaschek in the comments  findViewByPosition is a method of LayoutManager so it would work with all LayoutManagers  i e  StaggeredGridLayoutManager  etc

User · Answer

You can make ArrayList of ViewHolder     ArrayList lt MyViewHolder gt  myViewHolders   new ArrayList lt  gt      ArrayList lt MyViewHolder gt  myViewHolders2   new ArrayList lt  gt       and  all store ViewHolder s  in the list like      Override     public void onBindViewHolder  NonNull final MyViewHolder holder  final int position            final String str   arrayList get position            myViewHolders add position holder       and add remove other ViewHolder in the ArrayList as per your requirement

User · Answer

If you guys are having null with every attempt to get a view with any int position  try to add a new constructor parameter to your adapter like this for example  class RecyclerViewTableroAdapter  private val fichas  Array lt MFicha  gt   private val activity  View OnClickListener  private val indicesGanadores MutableList lt Int gt      RecyclerView Adapter lt RecyclerViewTableroAdapter ViewHolder gt        CODE     I added indicesGanadores to color my cardview background if my game is won  override fun onBindViewHolder holder  ViewHolder  position  Int      CODE if indicesGanadores contains position            holder cardViewFicha setCardBackgroundColor  activity as MainActivity  resources getColor R color DarkGreen           MORE CODE      If I don t have to color my background yet I just send an empty mutable list like this  binding recyclerViewMain adapter   RecyclerViewTableroAdapter fichasTablero  this MainActivity  mutableListOf lt Int gt      Happy coding

User · Answer

Keep in mind that you have to wait until adapter will added to list  then you can try to getting view by position  final int i   0  recyclerView setAdapter adapter   recyclerView post new Runnable          Override     public void run             View view   recyclerView getLayoutManager   findViewByPosition i

User · Answer

To get specific view from recycler view list OR show error at edittext of recycler view   private void popupErrorMessageAtPosition int itemPosition         RecyclerView ViewHolder viewHolder   recyclerView findViewHolderForAdapterPosition itemPosition       View view   viewHolder itemView      EditText etDesc    EditText  view findViewById R id et description       etDesc setError  Error message here

User · Answer

You can use use both  recyclerViewInstance findViewHolderForAdapterPosition adapterPosition   and recyclerViewInstance findViewHolderForLayoutPosition layoutPosition   Be sure that RecyclerView view uses two type of positions  Adapter position   Position of an item in the adapter  This is the position from the Adapter s perspective  Layout position   Position of an item in the latest layout calculation  This is the position from the LayoutManager s perspective  You should use getAdapterPosition   for findViewHolderForAdapterPosition adapterPosition  and getLayoutPosition   for findViewHolderForLayoutPosition layoutPosition    Take a member variable to hold previously selected item position in recyclerview adapter and other member variable to check whether user is clicking for first time or not   Sample code and screen shots are attached for more information at the bottom   public class MainActivity extends AppCompatActivity         private RecyclerView mRecyclerList   null      private RecyclerAdapter adapter   null        Override     protected void onCreate Bundle savedInstanceState            super onCreate savedInstanceState           setContentView R layout activity main            mRecyclerList    RecyclerView  findViewById R id recyclerList               Override     protected void onStart             RecyclerView LayoutManager layoutManager   null          String   daysArray   new String 15           String   datesArray   new String 15            super onStart            for  int i   0  i  lt  daysArray length  i                 daysArray i     Sunday               datesArray i     12 Feb 2017                      adapter   new RecyclerAdapter mRecyclerList  daysArray  datesArray           layoutManager   new LinearLayoutManager MainActivity this           mRecyclerList setAdapter adapter           mRecyclerList setLayoutManager layoutManager                     public class RecyclerAdapter extends RecyclerView Adapter lt RecyclerAdapter MyCardViewHolder gt              private final String TAG    RecyclerAdapter           private Context mContext   null          private TextView mDaysTxt   null  mDateTxt   null      private LinearLayout mDateContainerLayout   null      private String   daysArray   null  datesArray   null      private RecyclerView mRecyclerList   null      private int previousPosition   0      private boolean flagFirstItemSelected   false       public RecyclerAdapter RecyclerView mRecyclerList  String   daysArray  String   datesArray           this mRecyclerList   mRecyclerList          this daysArray   daysArray          this datesArray   datesArray              Override     public MyCardViewHolder onCreateViewHolder ViewGroup parent  int viewType            LayoutInflater layoutInflater   null          View view   null          MyCardViewHolder cardViewHolder   null          mContext   parent getContext            layoutInflater   LayoutInflater from mContext           view   layoutInflater inflate R layout date card row  parent  false           cardViewHolder   new MyCardViewHolder view           return cardViewHolder              Override     public void onBindViewHolder MyCardViewHolder holder  final int position            mDaysTxt   holder mDaysTxt          mDateTxt   holder mDateTxt          mDateContainerLayout   holder mDateContainerLayout           mDaysTxt setText daysArray position            mDateTxt setText datesArray position             if   flagFirstItemSelected               mDateContainerLayout setBackgroundColor Color GREEN               flagFirstItemSelected   true           else               mDateContainerLayout setBackground null                         Override     public int getItemCount             return daysArray length             class MyCardViewHolder extends RecyclerView ViewHolder          TextView mDaysTxt   null  mDateTxt   null          LinearLayout mDateContainerLayout   null          LinearLayout linearLayout   null          View view   null          MyCardViewHolder myCardViewHolder   null           public MyCardViewHolder View itemView                super itemView               mDaysTxt    TextView  itemView findViewById R id daysTxt               mDateTxt    TextView  itemView findViewById R id dateTxt               mDateContainerLayout    LinearLayout  itemView findViewById R id dateContainerLayout                mDateContainerLayout setOnClickListener new View OnClickListener                      Override                 public void onClick View v                        LinearLayout linearLayout   null                      View view   null                       if  getAdapterPosition      previousPosition                           view   mRecyclerList findViewHolderForAdapterPosition previousPosition  itemView                          linearLayout    LinearLayout  view findViewById R id dateContainerLayout                           linearLayout setBackgroundColor Color GREEN                           previousPosition   getAdapterPosition                          else                           view   mRecyclerList findViewHolderForAdapterPosition previousPosition  itemView                          linearLayout    LinearLayout  view findViewById R id dateContainerLayout                           linearLayout setBackground null                            view   mRecyclerList findViewHolderForAdapterPosition getAdapterPosition    itemView                          linearLayout    LinearLayout  view findViewById R id dateContainerLayout                           linearLayout setBackgroundColor Color GREEN                           previousPosition   getAdapterPosition

User · Answer

To get a View from a specific position of recyclerView you need to call findViewHolderForAdapterPosition position  on recyclerView object that will return RecyclerView ViewHolder  from the returned RecyclerView ViewHolder object with itemView you can access all Views at that particular position  RecyclerView ViewHolder rv view   recyclerView findViewHolderForAdapterPosition position    ImageView iv wish   rv view itemView findViewById R id iv item

User · Answer

This is what you re looking for   I had this problem too   And like you  the answer is very hard to find   But there IS an easy way to get the ViewHolder from a specific position  something you ll probably do a lot in the Adapter    myRecyclerView findViewHolderForAdapterPosition pos    NOTE   If the View has been recycled  this will return null   Thanks to Michael for quickly catching my important omission

User · Answer

You can use below mRecyclerview getChildAt pos

User · Answer

If you want the View  make sure to access the itemView property of the ViewHolder like so  myRecyclerView findViewHolderForAdapterPosition pos  itemView

User · Answer

You can get a view for a particular position on a recyclerview using the following   int position   2  RecyclerView ViewHolder viewHolder   recyclerview findViewHolderForItemId position   View view   viewHolder itemView  ImageView imageView    ImageView view findViewById R id imageView

User · Answer

You can as well do this  this will help when you want to modify a view after clicking a recyclerview position item   Override public void onClick View view  int position                 View v    rv notifications getChildViewHolder view  itemView              TextView content   v findViewById R id tv content               content setText  Helloo

User · Answer

You can simply use  findViewHolderForAdapterPosition  method of recycler view and you will get a viewHolder object from that then typecast that viewholder into your adapter viewholder so you can directly access your viewholder s views   following is the sample code for kotlin    val viewHolder   recyclerView findViewHolderForAdapterPosition position   val textview  viewHolder as YourViewHolder  yourTextView

[java] RecyclerView - Get view at particular position

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