There are certain conditions when you need to use nested gridview or gridview as an item of parent gridview.

Step 1:- Create an xml file.

A) xml that contain the parent_gridview_item.xml

<GridView
    android:id="@+id/parent_gridview"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:horizontalSpacing="5dp"
    android:listSelector="@android:color/transparent"
    android:numColumns="3"
    android:scrollbars="none"
    android:stretchMode="columnWidth"
    android:verticalSpacing="4dp">
</GridView>

B) xml that contain the child_gridview_item.xml for parent gridview.

<GridView
    android:id="@+id/child_gridview"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:horizontalSpacing="5dp"
    android:listSelector="@android:color/transparent"
    android:numColumns="3"
    android:scrollbars="none"
    android:stretchMode="columnWidth"
    android:verticalSpacing="4dp">
</GridView>

C) xml that contain the item for item.xml

<TextView
    android:id="@+id/tv_date"
    android:layout_width="16dp"
    android:layout_height="16dp"
    android:layout_gravity="center"
    android:gravity="center"
    android:padding="@dimen/dp_3"/>

Step 2: create the adapter to enfill gridview_parent.

public class ParentGridviewAdapter extends BaseAdapter
 {
    Activity activity;
    ChildGridViewAdapter childGridViewAdapter;
    ArrayList<Integer> dateList;

    public ParentGridviewAdapter(Activity activity) 
    {
      for(int i=0;i<9;i++)
        {
          dateList.add(i);
        }
        this.activity = activity;
    }
    @Override
    public int getCount() 
    {
        return dateList.size();
    }
    @Override
    public Object getItem(int i)
    {
        return dateList.get(i);
    }
    @Override
    public long getItemId(int i) 
    {
        return 0;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup viewGroup) 
     {
      final ViewHolder holder;
      LayoutInflater inflater;
     inflater=(LayoutInflater) activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
       
       if (convertView == null) 
        {
            convertView = inflater.inflate(R.layout.child_gridview_item, null);
        }
        holder = new ParentGridviewAdapter.ViewHolder(convertView);

        childGridViewAdapter = new ChildGridViewAdapter(activity);
        holder.gridView.setAdapter(childGridViewAdapter);
        return convertView;
    }
    private class ViewHolder 
     {
        private InnerGridView gridView;
        public ViewHolder(View v) {
        gridView = (InnerGridView) v.findViewById(R.id.child_gridview);
     }
   }

Step 3: create the adapter to enfill gridview _child.

public class ChildGridviewAdapter extends BaseAdapter
 {
    Activity activity;
    ArrayList<Integer> countList;

    public ChildGridviewAdapter(Activity activity) 
    {
      for(int i=0;i<4;i++)
        {
          countList.add(i);
        }
        this.activity = activity;
    }
    @Override
    public int getCount() 
    {
        return countList.size();
    }
    @Override
    public Object getItem(int i)
    {
        return countList.get(i);
    }
    @Override
    public long getItemId(int i) 
    {
        return 0;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup viewGroup) 
     {
      final ViewHolder holder;
      LayoutInflater inflater;
     inflater=(LayoutInflater) activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
       
       if (convertView == null) 
        {
            convertView = inflater.inflate(R.layout.item, null);
        }
        holder = new ChildGridviewAdapter.ViewHolder(convertView);
        holder.textv.setText(countList.get(position)+"")
        return convertView;
    }
    private class ViewHolder 
     {
        private TextView textv;
        public ViewHolder(View v) {
        textv = (TextView) v.findViewById(R.id.tv_date);
     }
   }