问题
I'm working on Expandable ListView and used this tutorial.
https://www.androidhive.info/2013/07/android-expandable-list-view-tutorial/
But what I'm looking for is that I want a child view with horizontal scroll view. I have an image and a text view inside for my child view. It is working vertically but I want it to work as horizontally. I've seen some other tutorials but none of them works. Can anyone tell me how can I make it work horizontally?
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>
adapter_view:
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;
}
}
回答1:
To have children view in horizontal instead of vertical then what I found from a solution is that we can return a recycler view instead of our own views and then to return our own views we can set that data to a recycler view using adapter just like we always do. Below is adapter code to help:
Expendable List View Adapter:
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;
}
}
Now the child adapter we need to set up data for the recycler view data is below:\
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);
}
}
}
Now to send the data from Main Class you need to create a model for parent with the array list of child.. Like a Category has 3 sub categories now all the sub categories will be added into an array list and that arraylist will be added with the model of parent child...
Ex:
Model m = new Model(categoryID,categoryName,ArrayList<subCategory> model)
来源：https://stackoverflow.com/questions/63046952/expandable-list-view-with-horizontalscroll-view-for-child-view