Creating an expandable RecyclerView

Question

I\'m trying to implement a recyclerview that behaves like my sketch below:

The idea is that there is a parent list, when an list item in the parent list is tapp

Answer 1

You can check my library in here

And create something like below code:

public class PurchaseItemRecyclerViewAdapter extends  ExpandableRecyclerView.Adapter
{

List itemModels;

public PurchaseItemRecyclerViewAdapter() {
    this.itemModels = new ArrayList<>();
    itemModels.add(new ItemModel("group 0",3,"subitem :"));
    itemModels.add(new ItemModel("group 1",3,"subitem :"));
    itemModels.add(new ItemModel("group 2",2,"subitem :"));
    itemModels.add(new ItemModel("group 3",1,"subitem :"));
    itemModels.add(new ItemModel("group 4",3,"subitem :"));
    itemModels.add(new ItemModel("group 5",5,"subitem :"));
}

@Override
public int getGroupItemCount() {
    return itemModels.size();
}

@Override
public int getChildItemCount(int i) {
    return itemModels.get(i).getSubItemCount();
}

@Override
public String getGroupItem(int i) {
    return itemModels.get(i).getParentName();
}

@Override
public String getChildItem(int group, int child) {
    return itemModels.get(group).getSubItemPrefix() + child;
}

@Override
protected ExpandableRecyclerView.SimpleGroupViewHolder onCreateGroupViewHolder(ViewGroup parent)
{
    return new ExpandableRecyclerView.SimpleGroupViewHolder(parent.getContext());
}

@Override
protected ChildViewHolder onCreateChildViewHolder(ViewGroup parent, int viewType)
{
    View rootView = LayoutInflater.from(parent.getContext()).inflate(R.layout.purchase_list_content,parent,false);
    return new ChildViewHolder(rootView);
}

@Override
public void onBindGroupViewHolder(ExpandableRecyclerView.SimpleGroupViewHolder holder, int group) {
    super.onBindGroupViewHolder(holder, group);
    holder.setText(getGroupItem(group));

}

@Override
public void onBindChildViewHolder(ChildViewHolder holder, final int group, int position)
{
    super.onBindChildViewHolder(holder, group, position);
    holder.name.setText(getChildItem(group, position));
    holder.itemView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            itemModels.get(group).setParentName("edited Parent");
            notifyItemChanged(group);
        }
    });
}

@Override
public int getChildItemViewType(int i, int i1) {
    return 1;
}

public class ChildViewHolder extends RecyclerView.ViewHolder
{
    private TextView name;
    public ChildViewHolder(View itemView) {
        super(itemView);
        name = (TextView) itemView.findViewById(R.id.item_name);
    }
}
}

and this ItemModel class:

public class ItemModel {
String parentName;
int subItemCount;
String subItemPrefix;

public ItemModel(String parentName, int subItemCount, String subItemPrefix) {
    this.parentName = parentName;
    this.subItemCount = subItemCount;
    this.subItemPrefix = subItemPrefix;
}

public String getParentName() {
    return parentName;
}

public void setParentName(String parentName) {
    this.parentName = parentName;
}

public int getSubItemCount() {
    return subItemCount;
}

public void setSubItemCount(int subItemCount) {
    this.subItemCount = subItemCount;
}

public String getSubItemPrefix() {
    return subItemPrefix;
}

public void setSubItemPrefix(String subItemPrefix) {
    this.subItemPrefix = subItemPrefix;
}
}