DatePicker - Posts - OneCompiler

<?xml version="1.0" encoding="utf-8"?>

<Button
    android:id="@+id/btn"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_margin="50dp"
    android:layout_marginStart="50dp"
    android:layout_marginLeft="50dp"
    android:layout_marginTop="50dp"
    android:layout_marginEnd="50dp"
    android:layout_marginRight="50dp"
    android:layout_marginBottom="50dp"
    android:text="Pick Date" />

<TextView
    android:id="@+id/tv"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_margin="50dp"
    android:layout_marginStart="50dp"
    android:layout_marginLeft="50dp"
    android:layout_marginTop="50dp"
    android:layout_marginEnd="50dp"
    android:layout_marginRight="50dp"
    android:layout_marginBottom="50dp"
    android:text="Today's Date" />

</LinearLayout>

Java:
package com.example.datepicker;

import androidx.appcompat.app.AppCompatActivity;

import android.app.DatePickerDialog;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.DatePicker;
import android.widget.TextView;
import android.widget.Toast;

import org.w3c.dom.Text;

import java.util.Calendar;

public class MainActivity extends AppCompatActivity {

private TextView tv;
private Button btn;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    tv = (TextView)findViewById(R.id.tv);
    btn = (Button)findViewById(R.id.btn);

    btn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            showDatePicker();
        }
    });


}
private void showDatePicker(){
    Calendar calendar = Calendar.getInstance();
    int year = calendar.get(Calendar.YEAR);
    int month = calendar.get(Calendar.MONTH);
    int day = calendar.get(Calendar.DAY_OF_MONTH);

    DatePickerDialog datePickerDialog = new DatePickerDialog(MainActivity.this,
            new DatePickerDialog.OnDateSetListener() {
                @Override
                public void onDateSet(DatePicker view, int year, int month, int dayOfMonth) {
                    String selectedDate = dayOfMonth + "/" + (month + 1) + "/" + year;
                    tv.setText(selectedDate);
                    Toast.makeText(MainActivity.this, selectedDate, Toast.LENGTH_SHORT).show();
                }
            }, year, month, day);

    datePickerDialog.show();

}

}