子视图的带有 Horizo​​ntalScroll View 的可扩展列表视图

Question

我正在开发可扩展的 ListView 并使用了本教程。

https://www.androidhive.info/2013/07/android-expandable-list-view-tutorial/

但我正在寻找的是我想要一个带有水平滚动视图的子视图。我的子视图内部有一个图像和一个文本视图。它垂直工作，但我希望它水平工作。我看过其他一些教程，但没有一个有效。谁能告诉我如何让它水平工作？

child_view：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@color/textFieldBackgroundColor"
android:orientation="vertical">

<ImageView
    android:id="@+id/imageViewChild"
    android:layout_width="80dp"
    android:layout_height="80dp"
    android:layout_gravity="center"
    android:layout_marginTop="10dp" />

<TextView
    android:id="@+id/tvChildName"
    android:layout_width="match_parent"
    android:layout_height="40dp"
    android:layout_marginTop="10dp"
    android:layout_marginBottom="15dp"
    android:fontFamily="@font/uber_move_text_regular"
    android:gravity="center"
    android:textAlignment="center"
    android:textColor="@color/alternateTextColor"
    android:textSize="19sp" />


</LinearLayout>

适配器视图：

 private Context _context;
    private List<String> _listDataHeader; // header titles
    // child data in format of header title, child title
    private HashMap<String, List<String>> _listDataChild;

    public ExListAdapter(Context context, List<String> listDataHeader,
                         HashMap<String, List<String>> listChildData) {
        this._context = context;
        this._listDataHeader = listDataHeader;
        this._listDataChild = listChildData;
    }

    @Override
    public Object getChild(int groupPosition, int childPosititon) {
        return this._listDataChild.get(this._listDataHeader.get(groupPosition))
                .get(childPosititon);
    }

    @Override
    public long getChildId(int groupPosition, int childPosition) {
        return childPosition;
    }

    @Override
    public View getChildView(int groupPosition, final int childPosition,
                             boolean isLastChild, View convertView, ViewGroup parent) {

        final String childText = (String) getChild(groupPosition, childPosition);

        if (convertView == null) {
            LayoutInflater infalInflater = (LayoutInflater) this._context
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = infalInflater.inflate(R.layout.categories_list_child, null);
        }

        TextView txtListChild = convertView
                .findViewById(R.id.tvChildName);

        ImageView imageViewChild = convertView.findViewById(R.id.imageViewChild);

      
        txtListChild.setText(childText);
        return convertView;
    }

    @Override
    public int getChildrenCount(int groupPosition) {
        return this._listDataChild.get(this._listDataHeader.get(groupPosition))
                .size();
    }

    @Override
    public Object getGroup(int groupPosition) {
        return this._listDataHeader.get(groupPosition);
    }

    @Override
    public int getGroupCount() {
        return this._listDataHeader.size();
    }

    @Override
    public long getGroupId(int groupPosition) {
        return groupPosition;
    }

    @Override
    public View getGroupView(int groupPosition, boolean isExpanded,
                             View convertView, ViewGroup parent) {
        String headerTitle = (String) getGroup(groupPosition);
        if (convertView == null) {
            LayoutInflater infalInflater = (LayoutInflater) this._context
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = infalInflater.inflate(R.layout.categories_list_header, null);
        }

        TextView lblListHeader = convertView
                .findViewById(R.id.tvHeader);

        lblListHeader.setTypeface(null, Typeface.BOLD);
        lblListHeader.setText(headerTitle);

        ImageView headerImage = convertView.findViewById(R.id.imageViewCatHeader);
      

        return convertView;
    }

    @Override
    public boolean hasStableIds() {
        return false;
    }

    @Override
    public boolean isChildSelectable(int groupPosition, int childPosition) {
        return true;
    }
}

Answer 1

要让子视图水平而不是垂直，那么我从一个解决方案中发现，我们可以返回一个回收器视图而不是我们自己的视图，然后返回我们自己的视图，我们可以使用适配器将该数据设置为回收器视图就像我们一直做的那样。以下是帮助的适配器代码：

消耗性列表视图适配器：

public class ExListAdapter implements ExpandableListAdapter {

private Context context;
private List<categoriesModel> listModel;

public ExListAdapter(Context context, List<categoriesModel> brands) {
    this.context = context;
    this.listModel = brands;
}

@Override
public void registerDataSetObserver(DataSetObserver observer) {
}

@Override
public void unregisterDataSetObserver(DataSetObserver observer) {

}

@Override
public int getGroupCount() {
    return listModel.size();
}

@Override
public int getChildrenCount(int groupPosition) {

 // you need to return 1 here instead of length of child views as our only view is recycler view
   

return 1;
}

@Override
public Object getGroup(int groupPosition) {
    return listModel.get(groupPosition);
}

@Override
public Object getChild(int groupPosition, int childPosition) {
    return listModel.get(groupPosition);
}

@Override
public long getGroupId(int groupPosition) {
    return groupPosition;
}

@Override
public long getChildId(int groupPosition, int childPosition) {
    return childPosition;
}

@Override
public boolean hasStableIds() {
    return true;
}

@SuppressLint("InflateParams")
@Override
public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {

    ParentHolder parentHolder = null;

    categoriesModel model = (categoriesModel) getGroup(groupPosition);

    if (convertView == null) {
        LayoutInflater userInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = userInflater.inflate(R.layout.categories_list_header, null);
        convertView.setHorizontalScrollBarEnabled(true);

        parentHolder = new ParentHolder();
        convertView.setTag(parentHolder);

    } else {
        parentHolder = (ParentHolder) convertView.getTag();
    }

    parentHolder.tvHeader = convertView.findViewById(R.id.tvHeader);
    parentHolder.tvHeader.setText(model.getName());

    parentHolder.imageView = convertView.findViewById(R.id.imageViewCatHeader);

    if (model.getCategoryImageURL() != null) {
        //model.getBaseURL() + "/" +
        Picasso.with(context).load(model.getCategoryImageURL()).into(parentHolder.imageView);
    }


    return convertView;
}

@Override
public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {

    ChildHolder childHolder = null;
    if (convertView == null) {
        LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = inflater.inflate(R.layout.item_group_child, parent, false);
        childHolder = new ChildHolder();
        convertView.setTag(childHolder);
    } else {
        childHolder = (ChildHolder) convertView.getTag();
    }


   //here we are setting up child view with a recycler view.

    ChildHolder.horizontalListView = convertView.findViewById(R.id.childRecyclerView);
    LinearLayoutManager layoutManager = new LinearLayoutManager(context, LinearLayoutManager.HORIZONTAL, false);
    ChildHolder.horizontalListView.setLayoutManager(layoutManager);


    ChildAdapter horizontalListAdapter = new ChildAdapter(context, listModel.get(groupPosition).getChildModel());
    ChildHolder.horizontalListView.setAdapter(horizontalListAdapter);

    return convertView;
}

@Override
public boolean isChildSelectable(int groupPosition, int childPosition) {
    return false;
}

@Override
public boolean areAllItemsEnabled() {
    return false;
}

@Override
public boolean isEmpty() {
    return false;
}

@Override
public void onGroupExpanded(int groupPosition) {

}

@Override
public void onGroupCollapsed(int groupPosition) {

}

@Override
public long getCombinedChildId(long groupId, long childId) {
    return 0;
}

@Override
public long getCombinedGroupId(long groupId) {
    return 0;
}

private static class ChildHolder {
    static RecyclerView horizontalListView;
}

private static class ParentHolder {
    TextView tvHeader;
    ImageView imageView;
}

}

现在我们需要为回收站视图数据设置数据的子适配器如下：\

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

private Context context;
private List<subCategoriesModel> subCategoriesModelList;
private final static String TAG = "childAdapterClass";

public ChildAdapter(Context context, List<subCategoriesModel> mobiles) {
    this.context = context;
    this.subCategoriesModelList = mobiles;
}

@NonNull
@Override
public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
    LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View cardView = inflater.inflate(R.layout.categories_list_child, null, false);
    ViewHolder viewHolder = new ViewHolder(cardView);
    viewHolder.imageViewChild = cardView.findViewById(R.id.imageViewChild);
    viewHolder.tvChildName = cardView.findViewById(R.id.tvChildName);
    return viewHolder;
}

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

    ImageView imageView = holder.imageViewChild;

    if (subCategoriesModelList.get(position).getImageURL() != null) {
        //subCategoriesModelList.get(position).getBaseURL() + "/" +
        Picasso.with(context).load(subCategoriesModelList.get(position).getImageURL()).into(imageView);
    }

    TextView tvName = holder.tvChildName;
    tvName.setText(subCategoriesModelList.get(position).getName());

    LinearLayout layout = holder.linearLayout;

    layout.setOnClickListener(v -> {
       /* Bundle bundle = new Bundle();
        bundle.putString("subCatId", subCategoriesModelList.get(position).getId());
        Fragment fragment = new GetCategoriesFragment();
        fragment.setArguments(bundle);
        ((FragmentActivity) context).getSupportFragmentManager().beginTransaction()
                .replace(R.id.content_frame, fragment)
                .addToBackStack(null)
                .commit();
        Log.d(TAG, "adapter:"+subCategoriesModelList.get(position).getId());*/
    });




}

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

@Override
public void onAttachedToRecyclerView(@NonNull RecyclerView recyclerView) {
    super.onAttachedToRecyclerView(recyclerView);
}

public static class ViewHolder extends RecyclerView.ViewHolder {

    ImageView imageViewChild;
    TextView tvChildName;
    LinearLayout linearLayout;

    public ViewHolder(View itemView) {
        super(itemView);
        imageViewChild = itemView.findViewById(R.id.imageViewChild);
        tvChildName = itemView.findViewById(R.id.tvChildName);
        linearLayout = itemView.findViewById(R.id.linearLayout);
    }
}

}

现在要从主类发送数据，您需要为父类创建一个模型，其中包含子类的数组列表。就像一个类别有 3 个子类别一样，现在所有子类别都将添加到数组列表中，并且该数组列表将加上父子模型...

例如：

Model m = new Model(categoryID,categoryName,ArrayList<subCategory> model)