Insert data in firebase cloud in android

 Xml:-

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:padding="20dp"
    tools:context=".ui.home.HomeFragment">
<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textSize="20sp"
    android:text="Form"
    android:layout_gravity="center"
    android:textStyle="bold"/>

   <EditText
       android:id="@+id/name"
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:hint="Entername"/>
    <EditText
        android:id="@+id/address"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Address"/>
    <EditText
        android:id="@+id/pincode"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Pincode"/>
    <EditText
        android:id="@+id/mobilenumber"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Mobile Number"/>
    <Button
        android:id="@+id/submit"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Submit"
        android:layout_gravity="center"/>

</LinearLayout>

Java :- 

package com.niranjan.cloudfirebase.ui.home;

import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
import androidx.lifecycle.Observer;
import androidx.lifecycle.ViewModelProvider;

import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.firestore.DocumentReference;
import com.google.firebase.firestore.FirebaseFirestore;
import com.niranjan.cloudfirebase.R;

import java.util.HashMap;
import java.util.Map;

public class HomeFragment extends Fragment {
EditText name,address,pincode,mobilenumbr;
Button button;
    FirebaseFirestore firestore;
    FirebaseAuth auth;


    public View onCreateView(@NonNull LayoutInflater inflater,
                             ViewGroup container, Bundle savedInstanceState) {

        View root = inflater.inflate(R.layout.fragment_home, container, false);
        firestore=FirebaseFirestore.getInstance();
        auth=FirebaseAuth.getInstance();
        name = root.findViewById(R.id.name);
        address = root.findViewById(R.id.address);
        pincode = root.findViewById(R.id.pincode);
        mobilenumbr = root.findViewById(R.id.mobilenumber);
        button=root.findViewById(R.id.submit);
button.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        Map<String, String> map = new HashMap<>();
        map.put("name",name.getText().toString());
        map.put("address",address.getText().toString());
        map.put("pincode",pincode.getText().toString());
        map.put("mobilenumbr",mobilenumbr.getText().toString());
        firestore.collection("Address").document(auth.getCurrentUser().getUid())
                .collection("CurrentUser").add(map).addOnCompleteListener(new OnCompleteListener<DocumentReference>() {
            @Override
            public void onComplete(@NonNull Task<DocumentReference> task) {
                Toast.makeText(getActivity(), "Insert Sucessfull", Toast.LENGTH_SHORT).show();
            }
        });

    }
});


        return root;
    }
}