android - How to have a ListView/RecyclerView inside a parent RecyclerView?

Question

I want to add some child Views (List Items), which come to me from JSON formatted data. Each child list is under a parent list item row. How can I populate it in RecyclerView for each row item (Parent items with child list items)?

I have tried using RecyclerView within RecyclerView parent row (for populating child lists), but here child views are not visible.

Parent Adapter Class

public class DigitizedPrescAdapter extends RecyclerView.Adapter<DigitizedPrescAdapter.ListItemViewHolder>{
    private List<PrescriptionModal> prescriptionList;

    MedicinesInPrescAdapter adapter;

    public DigitizedPrescAdapter(List<PrescriptionModal> prescriptionListModal) {

        if (prescriptionListModal == null) {
            throw new IllegalArgumentException(
                    "PrescriptionList must not be null");
        }
        this.prescriptionList = prescriptionListModal;
    }

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

    @Override
    public void onBindViewHolder(
            ListItemViewHolder viewHolder, int position) {
        PrescriptionModal model = prescriptionList.get(position);

        viewHolder.prescnum.setText("Prescription "+ ++position);
        viewHolder.prescNo.setText("Prescription: "+model.getPrescriptionID());
        viewHolder.doctorType.setText("Type: "+model.getDoctorType());
        viewHolder.doctorName.setText("Doctor: "+model.getDoctorName());
        viewHolder.patientName.setText("Patient: "+model.getPatientName());

        adapter = new MedicinesInPrescAdapter(model.getLstproduct());
        viewHolder.lstMedicines.setAdapter(adapter);

    }

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

    public final static class ListItemViewHolder
            extends RecyclerView.ViewHolder {

        TextView prescnum;
        TextView prescNo;
        TextView doctorType;
        TextView patientName;
        TextView doctorName;
        CheckBox selectAll;
        RecyclerView lstMedicines;

        public ListItemViewHolder(View itemView) {
            super(itemView);
            prescnum = (TextView) itemView.findViewById(R.id.prescnum);
            prescNo = (TextView) itemView.findViewById(R.id.prescNo);
            doctorType = (TextView) itemView.findViewById(R.id.doctorType);
            patientName = (TextView) itemView.findViewById(R.id.patientName);
            doctorName = (TextView) itemView.findViewById(R.id.doctorName);
            selectAll = (CheckBox) itemView.findViewById(R.id.selectAll);
            lstMedicines = (RecyclerView) itemView.findViewById(R.id.lstAllMedicines);
            MyLinearLayoutManager layoutManager = new MyLinearLayoutManager(itemView.getContext(),LinearLayoutManager.VERTICAL,false);
            lstMedicines.setHasFixedSize(false);
            lstMedicines.setLayoutManager(layoutManager);
        }
    }
}

Child Adapter Class

public class MedicinesInPrescAdapter extends RecyclerView.Adapter<MedicinesInPrescAdapter.MedicineListItemViewHolder>{

    List<Modal_Product_List> prescriptionProducts;

    public MedicinesInPrescAdapter(List<Modal_Product_List> prescriptionListProd) {

        if (prescriptionListProd == null) {
            throw new IllegalArgumentException(
                    "PrescriptionProductList must not be null");
        }
        this.prescriptionProducts = prescriptionListProd;
    }

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

    @Override
    public void onBindViewHolder(
            MedicineListItemViewHolder viewHolder, int position) {
        Modal_Product_List modelMedicine = prescriptionProducts.get(position);

        viewHolder.medicineName.setText(modelMedicine.getMedicinename());
        viewHolder.medQty.setText(modelMedicine.getQuantity());
        viewHolder.days.setText("30");
        viewHolder.Amount.setText(modelMedicine.getQuantitybasedprice());
    }

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

    public final static class MedicineListItemViewHolder
            extends RecyclerView.ViewHolder {

        TextView medicineName;
        EditText medQty;
        TextView days;
        TextView Amount;
        CheckBox selectMe;

        public MedicineListItemViewHolder(View itemView) {
            super(itemView);
            medicineName = (TextView) itemView.findViewById(R.id.medicineName);
            medQty = (EditText) itemView.findViewById(R.id.medQty);
            days = (TextView) itemView.findViewById(R.id.days);
            Amount = (TextView) itemView.findViewById(R.id.amount);
            selectMe = (CheckBox) itemView.findViewById(R.id.selectMe);
        }
    }
}

Answer 1

I got this issue few days ago and finally solved it. All you have to do is @override the layout manager onMeasure function as below:

CustomLinearLayoutManager

public class CustomLinearLayoutManager extends LinearLayoutManager {

    private static final String TAG = CustomLinearLayoutManager.class.getSimpleName();

    public CustomLinearLayoutManager(Context context) {
        super(context);
    }

    public CustomLinearLayoutManager(Context context, int orientation, boolean reverseLayout) {
        super(context, orientation, reverseLayout);
    }

    private int[] mMeasuredDimension = new int[2];

    @Override
    public void onMeasure(RecyclerView.Recycler recycler, RecyclerView.State state, int widthSpec, int heightSpec) {

        final int widthMode = View.MeasureSpec.getMode(widthSpec);
        final int heightMode = View.MeasureSpec.getMode(heightSpec);
        final int widthSize = View.MeasureSpec.getSize(widthSpec);
        final int heightSize = View.MeasureSpec.getSize(heightSpec);

        int width = 0;
        int height = 0;
        for (int i = 0; i < getItemCount(); i++) {
            measureScrapChild(recycler, i, View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
                View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
                mMeasuredDimension);


            if (getOrientation() == HORIZONTAL) {
                width = width + mMeasuredDimension[0];
                if (i == 0) {
                    height = mMeasuredDimension[1];
                }
            } else {
                height = height + mMeasuredDimension[1];
                if (i == 0) {
                    width = mMeasuredDimension[0];
                }
            }
        }
        switch (widthMode) {
            case View.MeasureSpec.EXACTLY:
                width = widthSize;
            case View.MeasureSpec.AT_MOST:
            case View.MeasureSpec.UNSPECIFIED:
        }

        switch (heightMode) {
            case View.MeasureSpec.EXACTLY:
                height = heightSize;
            case View.MeasureSpec.AT_MOST:
            case View.MeasureSpec.UNSPECIFIED:
        }

        setMeasuredDimension(width, height);
    }

    private void measureScrapChild(RecyclerView.Recycler recycler, int position, int widthSpec,
                               int heightSpec, int[] measuredDimension) {
        try {
            View view = recycler.getViewForPosition(0);//fix IndexOutOfBoundsException

            if (view != null) {
                RecyclerView.LayoutParams p = (RecyclerView.LayoutParams) view.getLayoutParams();

                int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec,
                    getPaddingLeft() + getPaddingRight(), p.width);

                int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec,
                    getPaddingTop() + getPaddingBottom(), p.height);

                view.measure(childWidthSpec, childHeightSpec);
                measuredDimension[0] = view.getMeasuredWidth() + p.leftMargin + p.rightMargin;
                measuredDimension[1] = view.getMeasuredHeight() + p.bottomMargin + p.topMargin;
                recycler.recycleView(view);
            }
        } catch (Exception e) {
            e.printStackTrace();
        } 
    }
}

You can just copy and paste the custom layout manager as above and in set up your recyclerview in the parent adapter like this:

RecyclerView.LayoutManager layoutManager = new CustomLinearLayoutManager(mContext);
holder.childRecyclerView.setLayoutManager(layoutManager);

Remember : Don't use same layoutManager as parent adapter, or error will occur.