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In Recycle view how to Highlight always one adapter item with the click and without click

由 半腔热情 提交于 2019-12-20 07:52:51

问题


Here I clicked on the item to change item background and color. I've stored the clicked item value in the database and change the layout color and text color and recreating the adapter and showing the list again while refreshing. But layout colors not changed when I get its position. Please show the right path to handle the set of background item color always.

public class LoadVehicleTypeAdapter extends RecyclerView.Adapter<LoadVehicleTypeAdapter.CarTypesHolder> {

    private List<TaxiTypeResponse.Message> CarTypesModelsList;
    private Context mContext;
    VehicleTypeView vehicleTypeView;
    int I = -1;
    int idd = 0;
    int II = 0;
    Activity activity;
    GoogleMap map;
    List<VehicleClick> list;

    private SparseBooleanArray selectedItems;

    public class CarTypesHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
        public CustomTextView mCarType;
        public CircleImageView mCarTypeImage;
        LinearLayout llRoot;
        CardView cardView;
        setOnitemclick listener;

        public void setOnItemClickListner(setOnitemclick listener) {
            this.listener = listener;
        }

        public CarTypesHolder(View view) {
            super(view);

            mCarType = (CustomTextView) view.findViewById(R.id.frag_cartypes_inflated_name);
            mCarTypeImage = (CircleImageView) view.findViewById(R.id.frag_cartype_inflated_frameImage);
            llRoot = (LinearLayout) view.findViewById(R.id.root1);
            selectedItems = new SparseBooleanArray();
            view.setOnClickListener(this);
        }

        @Override
        public void onClick(View v) {
            listener.ImageClick(v, getAdapterPosition());
        }
    }

    public LoadVehicleTypeAdapter(Context context, List<TaxiTypeResponse.Message> CarTypesModelsList, VehicleTypeView vehicleTypeView, Activity activity, GoogleMap map, List<VehicleClick> lists) {

        this.CarTypesModelsList = CarTypesModelsList;
        mContext = context;
        this.vehicleTypeView = vehicleTypeView;
        this.activity = activity;
        this.map = map;
        this.list = lists;
    }

    @Override
    public CarTypesHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View itemView = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.frag_cartype_inflated_view, parent, false);
        return new CarTypesHolder(itemView);
    }

    @SuppressLint("ResourceType")
    @Override
    public void onBindViewHolder(final CarTypesHolder holder, int position) {


        if (list.size() != 0) {
            II = Integer.parseInt(list.get(0).RideId);
            //setSelection(Integer.parseInt(list.get(0).RideId));
        }

        if (II == position) {
            holder.llRoot.setBackgroundColor(Color.parseColor("#999999"));
            holder.mCarType.setTextColor(Color.parseColor("#FFFFFF"));
        } else {
            holder.llRoot.setBackgroundColor(Color.parseColor("#f3f3f3"));
            holder.mCarType.setTextColor(Color.parseColor("#2196F3"));
        }

        SharedPreferences sharedPreferences = activity.getSharedPreferences("mSelected", Context.MODE_PRIVATE);
        TaxiTypeResponse.Message carTypesModel = CarTypesModelsList.get(position);
        holder.mCarType.setText(carTypesModel.getName());
        holder.mCarTypeImage.setBackgroundResource(R.drawable.wait);
        int color = Color.parseColor(PreferenceHandler.readString(mContext, PreferenceHandler.SECONDRY_COLOR, "#006fb6"));
        holder.mCarType.setTextColor(color);

        holder.setOnItemClickListner(new setOnitemclick() {
            @Override
            public void ImageClick(View v, int position1) {
                I = position1;
                notifyDataSetChanged();
                try {
                    if (list.size() != 0) {
                        VehicleTypeFragment.myAppRoomDataBase.userDao().delete();
                        list.clear();
                    }
                    VehicleClick vehicleClick = new VehicleClick();
                    vehicleClick.setRideId(String.valueOf(position1));
                    VehicleTypeFragment.myAppRoomDataBase.userDao().insert(vehicleClick);
                    list.add(vehicleClick);
                } catch (Exception e) {

                }

            }
        });

        if (I == position) {
            holder.llRoot.setBackgroundColor(Color.parseColor("#999999"));
            holder.mCarType.setTextColor(Color.parseColor("#ffffff"));
            Animation bounce = AnimationUtils.loadAnimation(mContext, R.anim.bounce);
            holder.llRoot.startAnimation(bounce);
        } else {
            holder.llRoot.setBackgroundColor(Color.parseColor("#f3f3f3"));
            holder.mCarType.setTextColor(Color.parseColor("#2196F3"));
        }

        Picasso.with(mContext).load(carTypesModel.getImagePath()).into(holder.mCarTypeImage);
    }

    @Override
    public long getItemId(int position) {
        return CarTypesModelsList.get(position).getID();
    }

    @Override
    public int getItemCount() {
        return CarTypesModelsList.size();
    }

    public void setSelection(int position) {
        II = position;
        //notifyDataSetChanged();
    }

    public interface setOnitemclick {
        void ImageClick(View view, int position);
    }

    @Override
    public int getItemViewType(int position) {
        return position;
    }
}

回答1:


I am not sure what did you mean by refreshing your list. I am guessing that you are recreating the adapter and showing the list again while you are refreshing. Hence the value of I is initialized with -1 each time you are creating the adapter.

You need to do the initialization as follows. Please consider the following is a pseudo code and you need to implement this of your own. 

// While declaring your I 
// int I = -1;
int I = getTheStoredValueFromDatabase(); // If there is no entry in database, getTheStoredValueFromDatabase function will return -1

I hope you get the idea. You might consider doing the same for other stored values.




回答2:


for keep track record you need to add Boolean variable in TaxiTypeResponse.Message boolean isClick=false; and toggle this in 

holder.setOnItemClickListner(new setOnitemclick() {

    @Override
    public void ImageClick(View v, int position) {
           CarTypesModelsList.get(position).isClick=!CarTypesModelsList.get(position).isClick;
           notifyDataSetChanged();
   }
}

and modify below code as follow

 if (CarTypesModelsList.get(position).isClick) {

        holder.llRoot.setBackgroundColor(Color.parseColor("#999999"));
        holder.mCarType.setTextColor(Color.parseColor("#ffffff"));
        Animation bounce = AnimationUtils.loadAnimation(mContext, R.anim.bounce);
        holder.llRoot.startAnimation(bounce);

 } 
 else{
        holder.llRoot.setBackgroundColor(Color.parseColor("#f3f3f3"));
        holder.mCarType.setTextColor(Color.parseColor("#2196F3"));
 }



回答3:


Note: onBindViewHolder() is not a place to implement the click listeners, but I am just providing you the logic for how to implement single selection in recyclerView.

Now lets jump to the solution, simply follow the below tutorial and change the variable, fields, and background according to your need, you have to implement the below method in onBindViewHolder() method of RecyclerView

First, initialize the lastClickedPosition and isclicked

    int lastPositionClicked = -1;
     boolean isClicked = false;

@Override
public void onBindViewHolder(@NonNull final MyViewHolder holder, final int position) {

    holder.YOUR_VIEW.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            // store the position which you have just clicked and you will change the background of this clicked view
            lastPositionClicked = position;
            isClicked = true;

            // need to refresh the adapter
            SlabAdapter.this.notifyDataSetChanged();
        }
    });

    // only change the background of last clicked item 
    if (isClicked && position == lastPositionClicked) {
        // change clicked view background color
    } else {
        // otherwise set the default color for all positions

    }
}

let me know if this works.




回答4:


on BindViewHolder method you'll use this code and set I=0 on globally

  @SuppressLint("ResourceType")
@Override
public void onBindViewHolder(final CarTypesHolder holder, int position) {

    SharedPreferences sharedPreferences = activity.getSharedPreferences("mSelected", Context.MODE_PRIVATE);
    TaxiTypeResponse.Message carTypesModel = CarTypesModelsList.get(position);
    holder.mCarType.setText(carTypesModel.getName());
    holder.mCarTypeImage.setBackgroundResource(R.drawable.wait);
    int color = Color.parseColor(PreferenceHandler.readString(mContext, PreferenceHandler.SECONDRY_COLOR, "#006fb6"));
    holder.mCarType.setTextColor(color);

    holder.setOnItemClickListner(new setOnitemclick() {
        @Override
        public void ImageClick(View v, int position1) {
            I = position1;
            notifyDataSetChanged();
            try {
                if (list.size() != 0) {
                    VehicleTypeFragment.myAppRoomDataBase.userDao().delete();
                    list.clear();
                }
                VehicleClick vehicleClick = new VehicleClick();
                vehicleClick.setRideId(String.valueOf(position1));
                VehicleTypeFragment.myAppRoomDataBase.userDao().insert(vehicleClick);
                list.add(vehicleClick);
            } catch (Exception e) {

            }

        }
    });

    if (I == position) {
        holder.llRoot.setBackgroundColor(Color.parseColor("#999999"));
        holder.mCarType.setTextColor(Color.parseColor("#ffffff"));
        Animation bounce = AnimationUtils.loadAnimation(mContext, R.anim.bounce);
        holder.llRoot.startAnimation(bounce);
    } else {
        holder.llRoot.setBackgroundColor(Color.parseColor("#f3f3f3"));
        holder.mCarType.setTextColor(Color.parseColor("#2196F3"));
    }

    Picasso.with(mContext).load(carTypesModel.getImagePath()).into(holder.mCarTypeImage);
}


来源：https://stackoverflow.com/questions/53812855/in-recycle-view-how-to-highlight-always-one-adapter-item-with-the-click-and-with

标签
java
android
android-recyclerview
recycler-adapter
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