Android 自定义LinearLayoutManager的父RecyclerView中的嵌套/子RecyclerView工作不正常

我尝试了下面介绍如何使用自定义的

LinearLayoutManager

，但是嵌套的

RecyclerView

根本没有显示

活动中的父RecyclerView： 父回收器视图的适配器： 请注意，子/嵌套回收视图位于

选项ViewHolder

内：

public class DishDetailsAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {

    private List<DishOption> options;
    private Context context;
    private SharedData sharedData = SharedData.getInstance();


    public DishDetailsAdapter(List<DishOption> detailsList, Context parentContext) {
        options = detailsList;
        context = parentContext;
        sharedData.setMainFont(context);
        sharedData.setSecondaryFont(context);
    }


    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

        LayoutInflater inflater = LayoutInflater.from(parent.getContext());

        View view = inflater.inflate(R.layout.category_dish_dialog_option, parent, false);
        RecyclerView.ViewHolder viewHolder = new OptionsViewHolder(view);

        return viewHolder;
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {

        DishOption dishOption = options.get(position);

        OptionsViewHolder vh = (OptionsViewHolder) holder;

        vh.optionName.setText(dishOption.getTitle());
        vh.optionName.setTypeface(sharedData.getSecondaryFont());

        List<DishOptionItem> dishOptionItems = dishOption.getItems();


        ItemsAdapter itemsAdapter = new ItemsAdapter(dishOptionItems, context);

        //NOTICE CHILD/NESTED RECYCLER VIEW HERE!!!!!!!!!!!!!!!!!!!!!!!
        vh.nestedRecyclerView.setAdapter(itemsAdapter);
        itemsAdapter.notifyDataSetChanged();

        LinearLayoutManager layoutManager = new NestedLinearLayoutManager(context, LinearLayoutManager.VERTICAL, false);

        vh.nestedRecyclerView.setLayoutManager(layoutManager);
    }

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


    /**
     * View holders for dish options Options
     */
    public class OptionsViewHolder extends RecyclerView.ViewHolder {

        private TextView optionName;
        private RecyclerView nestedRecyclerView;

        public OptionsViewHolder(View itemView) {
            super(itemView);


            optionName = (TextView) itemView.findViewById(R.id.dish_dialog_option_title);
            nestedRecyclerView = (RecyclerView) itemView.findViewById(R.id.category_nested_recycler_view);

        }
    }
}

公共类DishDetailsAdapter扩展了RecyclerView.Adapter{
私人名单选择；
私人语境；
private SharedData SharedData=SharedData.getInstance（）；
公共DishDetailsAdapter（列表详细信息列表，上下文父上下文）{
选项=详细信息列表；
上下文=父上下文；
setMainFont（上下文）；
sharedData.setSecondaryFont（上下文）；
}
@凌驾
public RecyclerView.ViewHolder onCreateViewHolder（视图组父级，int-viewType）{
LayoutInflater充气器=LayoutInflater.from（parent.getContext（））；
视图=充气机。充气（R.layout.category\u dish\u dialog\u选项，父项，false）；
RecyclerView.ViewHolder ViewHolder=新选项ViewHolder（视图）；
返回视图持有者；
}
@凌驾
BindViewHolder上的公共无效（RecyclerView.ViewHolder，int位置）{
DishOption DishOption=options.get（位置）；
选项视窗支架vh=（选项视窗支架）支架；
vh.optionName.setText（dishOption.getTitle（））；
vh.optionName.setTypeface（sharedData.getSecondaryFont（））；
List dishOptionItems=dishOption.getItems（）；
ItemsAdapter ItemsAdapter=新的ItemsAdapter（disoptionItems，上下文）；
//注意这里的儿童/嵌套回收者视图！！！！！！！！！！！！！！！！！！！！！！！
vh.NestedRecyclView.setAdapter（itemsAdapter）；
itemsAdapter.notifyDataSetChanged（）；
LinearLayoutManager布局管理器=新嵌套的LinearLayoutManager（上下文，LinearLayoutManager.VERTICAL，false）；
vh.nestedRecyclView.setLayoutManager（layoutManager）；
}
@凌驾
public int getItemCount（）{
返回选项。size（）；
}
/**
*查看盘子选项的支架
*/
公共类选项ViewHolder扩展了RecyclerView.ViewHolder{
私有文本视图选项名称；
私有回收视图嵌套回收视图；
公共选项ViewHolder（查看项目视图）{
超级（项目视图）；
optionName=（TextView）itemView.findViewById（R.id.dish\u dialog\u option\u title）；
nestedRecyclerView=（RecyclerView）itemView.findViewById（R.id.category\u nested\u RecyclerView）；
}
}
}

子/嵌套的RecyclerView适配器：

公共类ItemsAdapter扩展了RecyclerView.Adapter{
私人清单项目；
私人语境；
private SharedData SharedData=SharedData.getInstance（）；
公共项适配器（列表项列表、上下文父上下文）{
项目=项目列表；
上下文=父上下文；
}
@凌驾
public RecyclerView.ViewHolder onCreateViewHolder（视图组父级，int-viewType）{
LayoutInflater充气器=LayoutInflater.from（parent.getContext（））；
视图=充气机。充气（R.layout.category\u dish\u dialog\u item，parent，false）；
RecyclerView.ViewHolder ViewHolder=新项目ViewHolder（视图）；
返回视图持有者；
}
@凌驾
BindViewHolder上的公共无效（RecyclerView.ViewHolder，int位置）{
DishOptionItem item=items.get（位置）；
ItemViewHolder iVH=（ItemViewHolder）holder；
iVH.itemName.setText（item.getName（））；
}
@凌驾
public int getItemCount（）{
返回items.size（）；
}
/**
*查看菜肴选项项目的支架
*/
公共类ItemViewHolder扩展了RecyclerView.ViewHolder{
私有文本视图项目名称；
私有文本视图项目价格；
公共项目视图持有者（查看项目视图）{
超级（项目视图）；
itemName=（TextView）itemView.findViewById（R.id.dish\u dialog\u item\u name）；
//itemPrice=（TextView）itemView.findViewById（R.id.dish\u dialog\u item\u price）；
}
}
}

最后，自定义LinearLayoutManager：

公共类NestedLinearLayoutManager扩展了LinearLayoutManager{
公共嵌套LinearLayoutManager（上下文上下文、int方向、布尔反转）{
超级（上下文、方向、反转）；
}
私有int[]mMeasuredDimension=新int[2]；
@凌驾
测量时的公共空隙（RecyclerView.Recycler Recycler，RecyclerView.State，
整数宽度规格、整数高度规格）{
最终int-widthMode=View.MeasureSpec.getMode（widthmspec）；
最终int heightMode=View.MeasureSpec.getMode（heightSpec）；
最终int-widthSize=View.MeasureSpec.getSize（widthSpec）；
最终int heightSize=View.MeasureSpec.getSize（heightSpec）；
整数宽度=0；
整数高度=0；
对于（int i=0；ipublic class DishDetailsAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {

    private List<DishOption> options;
    private Context context;
    private SharedData sharedData = SharedData.getInstance();


    public DishDetailsAdapter(List<DishOption> detailsList, Context parentContext) {
        options = detailsList;
        context = parentContext;
        sharedData.setMainFont(context);
        sharedData.setSecondaryFont(context);
    }


    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

        LayoutInflater inflater = LayoutInflater.from(parent.getContext());

        View view = inflater.inflate(R.layout.category_dish_dialog_option, parent, false);
        RecyclerView.ViewHolder viewHolder = new OptionsViewHolder(view);

        return viewHolder;
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {

        DishOption dishOption = options.get(position);

        OptionsViewHolder vh = (OptionsViewHolder) holder;

        vh.optionName.setText(dishOption.getTitle());
        vh.optionName.setTypeface(sharedData.getSecondaryFont());

        List<DishOptionItem> dishOptionItems = dishOption.getItems();


        ItemsAdapter itemsAdapter = new ItemsAdapter(dishOptionItems, context);

        //NOTICE CHILD/NESTED RECYCLER VIEW HERE!!!!!!!!!!!!!!!!!!!!!!!
        vh.nestedRecyclerView.setAdapter(itemsAdapter);
        itemsAdapter.notifyDataSetChanged();

        LinearLayoutManager layoutManager = new NestedLinearLayoutManager(context, LinearLayoutManager.VERTICAL, false);

        vh.nestedRecyclerView.setLayoutManager(layoutManager);
    }

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


    /**
     * View holders for dish options Options
     */
    public class OptionsViewHolder extends RecyclerView.ViewHolder {

        private TextView optionName;
        private RecyclerView nestedRecyclerView;

        public OptionsViewHolder(View itemView) {
            super(itemView);


            optionName = (TextView) itemView.findViewById(R.id.dish_dialog_option_title);
            nestedRecyclerView = (RecyclerView) itemView.findViewById(R.id.category_nested_recycler_view);

        }
    }
}

public class ItemsAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {

    private List<DishOptionItem> items;
    private Context context;
    private SharedData sharedData = SharedData.getInstance();

    public ItemsAdapter(List<DishOptionItem> itemsList, Context parentParentContext) {
        items = itemsList;
        context = parentParentContext;
    }

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

        LayoutInflater inflater = LayoutInflater.from(parent.getContext());

        View view = inflater.inflate(R.layout.category_dish_dialog_item, parent, false);
        RecyclerView.ViewHolder viewHolder = new ItemViewHolder(view);

        return viewHolder;
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {

        DishOptionItem item = items.get(position);

        ItemViewHolder iVH = (ItemViewHolder) holder;

        iVH.itemName.setText(item.getName());

    }

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


    /**
     * View holders for dish options Items
     */
    public class ItemViewHolder extends RecyclerView.ViewHolder {

        private TextView itemName;
        private TextView itemPrice;

        public ItemViewHolder(View itemView) {
            super(itemView);

            itemName = (TextView) itemView.findViewById(R.id.dish_dialog_item_name);
            //itemPrice = (TextView) itemView.findViewById(R.id.dish_dialog_item_price);
        }
    }

}

public class NestedLinearLayoutManager extends LinearLayoutManager {


    public NestedLinearLayoutManager(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];
                }
            }
        }

        // If child view is more than screen size, there is no need to make it wrap content. We can use original onMeasure() so we can scroll view.
        if (height < heightSize && width < widthSize) {

            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);
        } else {
            super.onMeasure(recycler, state, widthSpec, heightSpec);
        }
    }

    private void measureScrapChild(RecyclerView.Recycler recycler, int position, int widthSpec,
                                   int heightSpec, int[] measuredDimension) {

        View view = recycler.getViewForPosition(position);

        // For adding Item Decor Insets to view
        super.measureChildWithMargins(view, 0, 0);
        if (view != null) {
            RecyclerView.LayoutParams p = (RecyclerView.LayoutParams) view.getLayoutParams();
            int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec,
                    getPaddingLeft() + getPaddingRight() + getDecoratedLeft(view) + getDecoratedRight(view), p.width);
            int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec,
                    getPaddingTop() + getPaddingBottom() + getPaddingBottom() + getDecoratedBottom(view) , p.height);
            view.measure(childWidthSpec, childHeightSpec);

            // Get decorated measurements
            measuredDimension[0] = getDecoratedMeasuredWidth(view) + p.leftMargin + p.rightMargin;
            measuredDimension[1] = getDecoratedMeasuredHeight(view) + p.bottomMargin + p.topMargin;
            recycler.recycleView(view);
        }
    }
}