We Keep Coding

How to store items from inside onBindViewHolder to array

I have a number of buttons inside recycview
I just wanted to add them in array and then i get them to add to them some jobs.
At first i defined array name "buttons"
ToggleButton buttons[] = new ToggleButton[5];
Then i put values in it
buttons[position]=holder.playBtn;
Now I want to press one of them
change all the backgrounds of all buttons
And so i used this function :
closeAll()
,but I didn't succeeding
// My class
public class MyListAdapter extends RecyclerView.Adapter<MyListAdapter.ViewHolder> {
public RecyclerViewClickListener mListener;
private MyListData[] listdata;
private Context context;
private ToggleButton [] listBtnPlyStop = null;
ToggleButton buttons[] = new ToggleButton[5];
public MyListAdapter(Context context ,MyListData[] listdata , RecyclerViewClickListener mListener) {
this.mListener =mListener;
this.listdata = listdata;
this.context = context;
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext());
View listItem= layoutInflater.inflate(R.layout.row_list_azcar, parent, false);
ViewHolder viewHolder = new ViewHolder(listItem);
return viewHolder;
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
final MyListData myListData = listdata[position];
holder.textView.setText(listdata[position].getDescription());
buttons[position]=holder.playBtn;
holder.playBtn.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener(){
#Override
public void onCheckedChanged(CompoundButton compoundButton, boolean checked) {
mListener.onClick(compoundButton,position);
setBgBtn(compoundButton,checked,position);
}
});
}
private void setBgBtn(CompoundButton compoundButton , boolean checked,int id) {
if(checked){
compoundButton.setBackground(ContextCompat.getDrawable(context, R.drawable.btnpause));
}else{
compoundButton.setBackground(ContextCompat.getDrawable(context, R.drawable.btnplay));
}
closeAll();
}
private void closeAll(){
for(int j=0; j<buttons.length-1;j++) {
buttons[j].setBackgroundResource(R.drawable.btnpause);
}
}
#Override
public int getItemCount() {
return listdata.length;
}
public static class ViewHolder extends RecyclerView.ViewHolder {
public ImageView imageView;
public TextView textView;
public LinearLayout linearLayout;
public ToggleButton toggleButton,playBtn;
public RadioButton radioButton1,radioButton2,radioButton3;
private RecyclerViewClickListener mListener;
public ViewHolder(View itemView){
super(itemView);
//this.itemView = itemView;
this.toggleButton =(ToggleButton) itemView.findViewById(R.id.bt_check2);
this.playBtn =(ToggleButton) itemView.findViewById(R.id.bt_play);
this.radioButton1 = (RadioButton)itemView.findViewById(R.id.radio_btn1);
this.radioButton2= (RadioButton)itemView.findViewById(R.id.radio_btn2);
this.radioButton3= (RadioButton)itemView.findViewById(R.id.radio_btn3);
this.textView = (TextView) itemView.findViewById(R.id._txt_kind_of_azkar);
linearLayout = (LinearLayout)itemView.findViewById(R.id.l_containe_row);
}
}
}

I would suggest creating a dynamic array list of ToggleButtons, like so:
private ArrayList<ToggleButton> buttons;
public MyListAdapter(Context context ,MyListData[] listdata , RecyclerViewClickListener mListener) {
this.mListener =mListener;
this.listdata = listdata;
this.context = context;
this.buttons = new ArrayList<>();
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext());
View listItem= layoutInflater.inflate(R.layout.row_list_azcar, parent, false);
ViewHolder viewHolder = new ViewHolder(listItem);
return viewHolder;
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
final MyListData myListData = listdata[position];
holder.textView.setText(listdata[position].getDescription());
buttons.add(holder.playBtn);
...
private void closeAll(){
for(int j=0; j<buttons.size(); j++) {
buttons.get(j).setBackgroundResource(R.drawable.btnpause);
}
}

Made a custom Adapter for my RecyclerView with a List

I want to make a custom Adapter for my RecyclerView because I need to use a custom method inside who will init my List later when my presenter will be ready:
public void setList(List<Object> data){
this.data = data;
}
This is my not custom interface for my Adapter without implementation.
final class AdapterReviews extends RecyclerView.Adapter<AdapterReviews.ReviewViewHolder> {}
The question is how should be the interface for my custom Adapter?

**public class GetHolidaylistAdapter extends RecyclerView.Adapter<GetHolidaylistAdapter.ViewHolder> {
ArrayList<HashMap<String, String>> arrayList;
public GetHolidaylistAdapter(ArrayList<HashMap<String, String>> arrayList) {
this.arrayList = arrayList;
}
public class ViewHolder extends RecyclerView.ViewHolder {
TextView holiyDay_Date_Tv, holidayName_tv, holidayType_tv, day_tv;
public ViewHolder(View itemView) {
super(itemView);
holiyDay_Date_Tv = (TextView) itemView.findViewById(R.id.holiyDay_Date_Tv);
holidayName_tv = (TextView) itemView.findViewById(R.id.holidayName_tv);
holidayType_tv = (TextView) itemView.findViewById(R.id.holidayType_tv);
}
}
#Override
public int getItemCount() {
return arrayList.size();
}
#NonNull
#Override
public ViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
GetHolidaylistAdapter.ViewHolder viewHolder = null;
Log.d(TAG, "Rv_Child_Active.." + viewType);
viewHolder = new GetHolidaylistAdapter.ViewHolder(LayoutInflater.from(parent.getContext()).
inflate(R.layout.holiday_child_rv, parent, false));
return viewHolder;
}
#Override
public void onBindViewHolder(#NonNull ViewHolder holder, int position) {
String date = arrayList.get(position).get(TAG_HOLIDAYDATE);
holder.holidayName_tv.setText(arrayList.get(position).get(TAG_HOLIDAYName));
holder.holiyDay_Date_Tv.setText(arrayList.get(position).get(TAG_HOLIDAYDATE));
holder.holidayType_tv.setText(arrayList.get(position).get(TAG_HOLIDAYtype));
***}
}
recycle_view=(RecyclerView)findViewById(R.id.recycle_view);
linearLayoutManager=new LinearLayoutManager(this);
recycle_view.setLayoutManager(linearLayoutManager);
adapter=new CustomAdapter(modelRecyclerArrayList);
recycle_view.setAdapter(adapter);
RecyclerView recycle_view;
LinearLayoutManager linearLayoutManager;
CustomAdapter adapter;
ArrayList<ModelRecycler> modelRecyclerArrayList = new ArrayList<>();*

A basic RecyclerView CustomAdapter looks like this
public class CustomAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private final Context context;
ArrayList<String> list = new ArrayList<>();
public CustomAdapter(Context context, ArrayList<String> list) { // you can pass other parameters in constructor
this.context = context;
this.list = list;
}
private class CustomAdapterItemView extends RecyclerView.ViewHolder {
final TextView textView;
CustomAdapterItemView(final View itemView) {
super(itemView);
textView = (TextView) itemView;
}
void bind(int position) {
textView.setText("");
}
}
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
return new CustomAdapterItemView(LayoutInflater.from(context).inflate(R.layout.item_color, parent, false));
}
#Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
((CustomAdapterItemView) holder).bind(position);
}
#Override
public int getItemCount() {
return list.size();
}
// Add your other methods here
}

You can check this. Here you have complete example of RecyclerView. It is all made by Google.

How to add a recyclerview item dynamically when click a button in another activity?

I have a recyclerview in ShoppingCartActivity and a button in ProductDetailActivity. I want to send some data to ShoppingCartActivity when a button clicked in ProductDetailActivity and display them in recyclerview item that creates dynamically in ShoppingCartActivity.
I added addData method to recyclerview Adapter but it doesn't work and app crashes.
shop_btn = findViewById(R.id.add_to_shopping_cart);
shop_btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent addToCart = new Intent(ProductDetailActivity.this, ShoppingCartActivity.class);
startActivity(addToCart);
}
});
//HERE IS MY RECYCLERVIEW ADAPTER
public class RecyclerViewAdapter_ShoppingCart extends RecyclerView.Adapter<RecyclerViewAdapter_ShoppingCart.MyViewHolder> {
private Context context;
List<CartItems> cartItemsList;
public RecyclerViewAdapter_ShoppingCart(Context context, List<CartItems> cartItemsList) {
this.context = context;
this.cartItemsList = cartItemsList;
}
#NonNull
#Override
public MyViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view;
LayoutInflater layoutInflater = LayoutInflater.from(context);
view = layoutInflater.inflate(R.layout.card_cart, parent, false);
return new MyViewHolder(view);
}
#NonNull
#Override
public void onBindViewHolder(#NonNull final MyViewHolder holder, final int position) {
holder.cart_title.setText(cartItemsList.get(position).getTitle());
holder.cart_price.setText(cartItemsList.get(position).getPrice());
Picasso.get().load(cartItemsList.get(position).getImageUrl()).into(holder.cart_img);
}
#Override
public int getItemCount() {
return cartItemsList.size();
}
public static class MyViewHolder extends RecyclerView.ViewHolder {
TextView cart_title, cart_price;
ImageView cart_img;
public MyViewHolder(View itemView) {
super(itemView);
cart_title = itemView.findViewById(R.id.cart_title);
cart_price = itemView.findViewById(R.id.cart_price);
//cart_delete = itemView.findViewById(R.id.cart_delete);
cart_img = itemView.findViewById(R.id.cart_image);
}
}
public void addItem(List<CartItems> cartItems) {
CartItems newValue = new CartItems();
newValue.setTitle("123");
newValue.setPrice("123");
newValue.setImageUrl("");
cartItems.add(newValue);
notifyDataSetChanged();
}
}
My goal is adding recyclerview items dynamically to ShoppingCartActivity when a button clicked in ProductDetailActivity but app crashes.

RecyclerView problem to load more than n items

I've implementend a RecyclerView as follow
The Adapter with the Holder
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyHolder> {
#NonNull
#Override
public MyHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext())
.inflate(R.layout.indovinelloelement,parent,false);
MyHolder holder = new MyHolder(view);
return holder;
}
#Override
public void onBindViewHolder(#NonNull MyHolder holder, int position) {
holder.category.setText(data.get(position).getCategory());
holder.difficulty.setText(""+data.get(position).getDifficulty());
holder.title.setText(data.get(position).getTitle());
holder.score.setText(""+data.get(position).getScore());
if(data.get(position).isLocked())
holder.setLocked();
else
holder.setUnlocked();
}
public DataGestour.Indovinello getIndovinello(int pos){
return data.get(pos);
}
#Override
public int getItemCount() {
return data.size();
}
public class MyHolder extends RecyclerView.ViewHolder {
public TextView category,score,difficulty,title;
private ImageView lock_state;
public MyHolder(View itemView) {
super(itemView);
category = (TextView)itemView.findViewById(R.id.categoria);
score = (TextView)itemView.findViewById(R.id.punteggio);
difficulty = (TextView) itemView.findViewById(R.id.difficolta);
title = (TextView)itemView.findViewById(R.id.titolo);
lock_state = (ImageView) itemView.findViewById(R.id.lock_state);
}
public void setLocked(){
lock_state.setImageResource(R.drawable.ic_lock_outline_black_24dp);
}
public void setUnlocked(){
lock_state.setImageResource(R.drawable.ic_lock_open_black_24dp);
}
}
ArrayList<DataGestour.Indovinello> data;
Context context;
public MyAdapter(Context context, ArrayList<DataGestour.Indovinello> list){
this.context = context;
this.data = list;
}
}
and the RecyclerView:
rc = (RecyclerView)root_view.findViewById(R.id.lista_domande);
rc.setHasFixedSize(true);
LinearLayoutManager ly = new LinearLayoutManager(getContext());
ly.setOrientation(LinearLayoutManager.VERTICAL);
rc.setLayoutManager(ly);
try{
gestour = new DataGestour(getContext());
}catch (IllegalStateException e){
Log.e("DataManager",e.getMessage());
};
adapter = new MyAdapter(getContext(),gestour.getAllDatas());
rc.setAdapter(adapter);
adapter.notifyDataSetChanged();
where DataGestoure is a class that manipulates some data from a
database and store them in a ArrayList (DataGestour.getAllDatas is the method to return the data under a ArrayList)
The problem start only if the ArrayList contains more then 3 items becouse the RecyclerView doen't show them despite the fact that the adapter holds all the data in ArrayList< DataGestour.Indovinello > data

Well, you need a little more order in your code, since it is not properly structured, by default the RecyclerView has its Scrolleable view unless in the XML this attribute is removed, well I recommend that you use this code in your adapter and use a model to save the information you get from your BD, that is the correct way to work to keep everything in order and it is easier to work it, once this is done you can use this code perfectly that I am sure will work, remember to only pass information to my Model that in my case calls it "Model" and with this the error of your data load will be solved. It is also advisable to use a List <> for these cases since the Arrays <> tend to have errors when you manipulate the data and more if you do it the way you present the code.
private List<Model> mDataList;
public MyAdapter(Context context){
this.context = context;
this.mDataList = new ArrayList<>();
}
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyHolder> {
#NonNull
#Override
public MyHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext())
.inflate(R.layout.indovinelloelement,parent,false);
return new MyHolder(view);
}
#Override
public void onBindViewHolder(#NonNull MyHolder holder, int position) {
MyHolder holder = (MyHolder) MyHolder;
hoder.bind(mDataList.getPosition(position));
}
#Override
public int getItemCount() {
return mDataList.size();
}
public void setData(List<Model> list) {
mDataList.clear();
mDataList.addAll(list);
notifyDataSetChanged();
}
public class MyHolder extends RecyclerView.ViewHolder {
TextView category;
category = (TextView)itemView.findViewById(R.id.categoria);
TextView score;
score = (TextView)itemView.findViewById(R.id.punteggio);
TextView difficulty;
difficulty = (TextView) itemView.findViewById(R.id.difficolta);
TextView title;
title = (TextView)itemView.findViewById(R.id.titolo);
ImageView lock_state;
lock_state = (ImageView) itemView.findViewById(R.id.lock_state);
public MyHolder(View itemView) {
super(itemView);
}
protected void bind(Model model){
category.setText(model.getCategory());
score.setText(model.getScore());
difficulty.setText(model.getDifficulty());
title.setText(model.getTitle());
if(model.isLocked()){
lock_state.setImageResource(R.drawable.ic_lock_outline_black_24dp);
} else {
lock_state.setImageResource(R.drawable.ic_lock_open_black_24dp);
}
}
}
}
And for your class that contains the RecyclerView use the code as follows.
RecyclerView mRecyclerView;
mRecyclerView = (RecyclerView)root_view.findViewById(R.id.lista_domande);
private MyAdapter mAdapter;
private List<Model> mDataList;
private DataGestour gestour;
private void setupRecyclerView(){
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(getContext());
linearLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.setLayoutManager(linearLayoutManager);
mAdapter = new MyAdapter(getContext());
mRecyclerView.setAdapter(mAdapter);
mRecyclerView.setData(mDataList);
}
private void getDataDB(){
mDataList.add(gestour.getAllDatas);
}

Unable to call method in Adapter from ViewHolder (RecyclerView)

I'm trying to delete an item from my RecyclerView when the user clicks on it. However, even though the delete method in the Adapter is public I get the error 'Cannot resolve method delete(int)' when trying to call 'delete' method from the onClick in MyViewHolder.
What gives? It's public so why can't I call it?
GroceryItemAdapter
public class GroceryItemAdapter extends RecyclerView.Adapter<MyViewHolder> {
private LayoutInflater inflater;
private Context context;
List<MetaData> data = Collections.emptyList();
public GroceryItemAdapter(Context context, List<MetaData> data) {
this.context = context;
inflater = LayoutInflater.from(context);
this.data = data;
}
public void delete(int position) {
data.remove(position);
notifyItemRemoved(position);
}
#Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = inflater.inflate(R.layout.grocery_item_row, parent, false);
MyViewHolder holder = new MyViewHolder(view);
Log.i("GroceryHero", "onCreateViewHolder called");
return holder;
}
#Override
public void onBindViewHolder(MyViewHolder holder, int position) {
MetaData current = data.get(position);
holder.title.setText(current.title);
holder.icon.setImageResource(current.iconid);
Log.i("GroceryHero","onBindViewHolder called " + position);
}
#Override
public int getItemCount() {
return data.size();
}
}
MyViewHolder:
class MyViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
TextView title;
ImageView icon;
public MyViewHolder(View itemView) {
super(itemView);
Log.i("GroceryHero", "MyViewHolder called");
title = (TextView) itemView.findViewById(R.id.grocery_text);
icon = (ImageView) itemView.findViewById(R.id.grocery_icon);
itemView.setOnClickListener(this);
}
#Override
public void onClick(View v) {
Toast.makeText(v.getContext(), "Item clicked at " + getAdapterPosition(), Toast.LENGTH_SHORT).show();
delete(getAdapterPosition()); // ERROR: Cannot resolve method
}
}

You're trying to call delete from the view holder class. But delete is a method of the adapter class. You can may be pass an instance of adapter to the view holder in onCreateViewHolder and store it as a private field.
GroceryItemAdapter mAdapter;
public MyViewHolder(View itemView, GroceryItemAdapter adapter) {
mAdapter = adapter;
...
}
// now you can call
mAdapter.delete(getAdapterPosition());