如何在父 RecyclerView 中有一个 ListView/RecyclerView？

Question

我想添加一些子视图（列表项），它们来自 JSON 格式化数据。每个子列表都在父列表项行下。如何在 RecyclerView 中为每个行项目（具有子列表项目的父项目）填充它？

我曾尝试在 RecyclerView 父行中使用 RecyclerView（用于填充子列表），但此处子视图不可见。

父适配器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);
        }
    }
}

子适配器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

据我了解，您需要一个带有 RecyclerView 行的 RecyclerView。在这种情况下，我建议您使用 可扩展的 RecyclerView，在 link.

中使用 this lib. Just follow the expandable example

同一个库中还有许多更酷的功能，例如拖放、可滑动行...观看不到一分钟 example video。

您只需将库添加到 gradle.build 文件中的依赖项中，如下所示：

dependencies {
    compile 'com.h6ah4i.android.widget.advrecyclerview:advrecyclerview:0.7.4'
}

能够 import 您 java 文件中的库。

Answer 2

前几天遇到这个问题，终于解决了。您所要做的就是 @override 布局管理器 onMeasure 函数，如下所示：

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();
        } 
    }
}

您只需像上面那样复制并粘贴自定义布局管理器，然后像这样在父适配器中设置您的回收视图：

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

记住 : 不要使用与父适配器相同的布局管理器，否则会发生错误。

Answer 3

通过 Android 支持库 23.2 的支持库版本 23.2.0。所以所有 WRAP_CONTENT 应该都能正常工作。

请更新 gradle 文件中的库版本。

compile 'com.android.support:recyclerview-v7:23.2.0'

这允许 RecyclerView 根据其内容的大小调整自身的大小。这意味着以前不可用的场景，例如将 WRAP_CONTENT 用于 RecyclerView 的维度，现在是可能的。您会发现所有内置的布局管理器现在都支持自动测量。

您需要致电 setAutoMeasureEnabled(true)

Below is the sample code

RecyclerView.LayoutManager layout = new LinearLayoutManager(context); 
layout.setAutoMeasureEnabled(true);

因为 setAutoMeasureEnabled 是不推荐使用的替代解决方案此方法已在 API 级别 27.1.0 中弃用。 LayoutManager 的实现者应该通过覆盖 isAutoMeasureEnabled().

来定义它是否使用 AutoMeasure

Answer 4

请注意：您不应在每次调用 onBindView() 时都创建新的 Adapter，您应该在 onCreateView() 中创建一次。

最好的方法 - 使用任何库，例如 - RendererRecyclerViewAdapter

如何添加 NestedRecyclerView：

第 1 步：将 ViewModel 界面添加到您的 Modal_Product_List

public class Modal_Product_List implements ViewModel {

    String getMedicinename() { ... } //your method
    int getQuantity() { ... } //your method
    int getQuantitybasedprice() { ... } //your method
}

步骤 2: 为 Modal_Product_List 创建一个 ViewBinder:

private ViewRenderer getModalProductViewRenderer() {
    return new ViewBinder<>(
            R.layout.item_row_medicine_productlist, //your child layout id
            Modal_Product_List.class //your child item class
            (model, finder, payloads) -> finder
                .setText(R.id.medicineName, model.getMedicinename())
                .setText(R.id.medQty, (String) model.getQuantity())
                .setText(R.id.amount, (String) model.getQuantitybasedprice())
                .setChecked(R.id.selectMe, ...)
    );
}

第 3 步： 将 CompositeViewModel 接口添加到 PrescriptionModal 或从 DefaultCompositeModel 扩展：

public class PrescriptionModal extends DefaultCompositeViewModel {

    String getPrescriptionID() {...} //your method
    String getDoctorType() {...} //your method
    String getDoctorName() {...} //your method
    String getPatientName() {...} //your method

    @Override
    List<Modal_Product_List> getItems() { return yourProductItems; }
}

步骤 4: 为 PrescriptionModal 创建一个 ViewBinder:

private ViewRenderer getModalProductViewRenderer() {
    return new CompositeViewBinder<>(
        R.layout.item_row_digitised_request, //your parent item layout
        R.id.lstAllMedicines, //your nested RecyclerView
        PrescriptionModal.class, //your parent item class
        (model, finder, payloads) -> finder
            //no need to set child items, it will set automatically
            .setText(R.id.prescnum, "Prescription:" + model.getPrescriptionID)
            .setText(R.id.doctorName, "Doctor:" + model.getDoctorName())
            .setText(R.id.doctorType, "Type:" + model.getDoctorType())
            .setText(R.id.patientName, "Patient:" + model.getPatientName())
    ).registerRenderer(getModalProductViewRenderer()); //register ModalProductViewRenderer
     .registerRenderer(...) //if you need you can create other renderer and register here
);

第 5 步（可选）： 如果您需要自定义 LayoutManager，则扩展 CompositeViewBinder 并覆盖 createLayoutManager 方法和用它代替 CompositeViewBinder

public class CustomCompositeViewBinder extends CompositeViewBinder {

    //...

    @Override
    protected RecyclerView.LayoutManager createLayoutManager() {
        return new MyLinearLayoutManager(getContext(), VERTICAL, false);
    }
}

第 6 步：初始化RendererRecyclerViewAdapter并注册渲染器：

RendererRecyclerViewAdapter adapter = new RendererRecyclerViewAdapter(getContext());
recyclerView.setAdapter(adapter);

adapter.registerRenderer(getModalProductViewRenderer());
adapter.registerRenderer(...); //if you need you can create other renderers

adapter.setItems(getPrescriptionListModal());

添加嵌套 RecyclerView 的方法非常简短

如何在父 RecyclerView 中有一个 ListView/RecyclerView？

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

android

android-recyclerview

父适配器Class

子适配器Class