How to create age calculator app in android studio

1. Activity (activity_main.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:background="#f7e9f0" android:orientation="vertical" tools:context=".MainActivity"> <Toolbar android:layout_width="match_parent" android:layout_gravity="center" android:layout_height="70dp"> <TextView android:layout_width="wrap_content" android:text="Anu Age Calculator" android:textColor="#ff3399" style="@style/Base.CardView" android:textSize="22dp" android:textStyle="bold" android:layout_height="wrap_content"> </TextView> </Toolbar> <Toolbar android:layout_width="match_parent" android:layout_gravity="center" android:background="@color/white" android:layout_height="1dp"/> <DatePicker android:id="@+id/datePicker" android:layout_width="wrap_content" android:layout_height="wrap_content" android:calendarViewShown="false" android:background="@color/black" android:scrollbars="vertical" android:visibility="gone" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@id/tvCurrentDate" /> <ScrollView android:layout_width="match_parent" android:layout_gravity="center" android:verticalScrollbarPosition="defaultPosition" android:layout_height="wrap_content"> <LinearLayout android:layout_width="match_parent" android:gravity="center_horizontal" android:background="#f7e9f0" android:orientation="vertical" android:layout_height="100dp"> <androidx.cardview.widget.CardView android:layout_width="match_parent" android:layout_height="300dp" android:layout_marginTop="10dp" android:elevation="8dp" app:cardBackgroundColor="@color/white" app:cardCornerRadius="20dp" app:cardUseCompatPadding="true" app:cardElevation="8dp"> <TextView android:id="@+id/TodayDates" android:layout_width="wrap_content" android:layout_height="wrap_content" android:padding="10dp" android:textStyle="bold" android:text="Today's Date" android:textColor="#697782" android:textSize="15sp" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" /> <androidx.cardview.widget.CardView android:id="@+id/cardView1" android:layout_width="match_parent" android:layout_height="100dp" android:layout_marginTop="20dp" android:backgroundTint="@android:color/white" android:elevation="8dp" android:radius="12dp" android:gravity="center" app:cardCornerRadius="12dp" app:cardElevation="8dp" app:cardUseCompatPadding="true"> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="vertical" android:layout_gravity="center_vertical" android:padding="16dp"> <TextView android:id="@+id/tvCurrentDate" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Current Date: " android:textColor="#899cab" android:textSize="18sp" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" /> <!-- Description --> </LinearLayout> </androidx.cardview.widget.CardView> <androidx.cardview.widget.CardView android:id="@+id/cardView2" android:layout_width="match_parent" android:layout_height="110dp" android:layout_marginTop="100dp" android:backgroundTint="@android:color/white" android:elevation="8dp" android:radius="12dp" android:gravity="center" app:cardCornerRadius="12dp" app:cardElevation="8dp" app:cardUseCompatPadding="true"> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="horizontal" android:layout_gravity="center_vertical" android:padding="16dp"> <TextView android:id="@+id/DOB" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Date Of Birth " android:textColor="#899cab" android:textSize="18sp" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" /> <Button android:id="@+id/selectdate" android:layout_width="100dp" android:layout_height="50dp" android:textColor="#ff3399" android:layout_marginLeft="90dp" android:text="Select" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" /> </LinearLayout> </androidx.cardview.widget.CardView> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="horizontal" android:layout_marginTop="95dp" android:layout_gravity="center_vertical" android:padding="16dp"> <Button android:id="@+id/Calculate" android:layout_width="120dp" android:layout_height="50dp" android:layout_marginLeft="90dp" android:text="Calculate" android:textColor="#ff3399" android:layout_marginStart="9dp" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" /> <Button android:id="@+id/clear" android:layout_width="100dp" android:layout_height="50dp" android:layout_marginLeft="90dp" android:textColor="#ff3399" android:text="Clear" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" /> </LinearLayout> </androidx.cardview.widget.CardView> <androidx.cardview.widget.CardView android:id="@+id/cardView3" android:layout_width="match_parent" android:layout_height="200dp" android:layout_marginTop="20dp" android:backgroundTint="@android:color/white" android:elevation="8dp" android:radius="12dp" android:gravity="center" app:cardCornerRadius="12dp" app:cardElevation="8dp" app:cardUseCompatPadding="true"> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="vertical" android:gravity="center" android:padding="16dp"> <TextView android:id="@+id/Dated" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Current Date: " android:textColor="#899cab" android:textSize="25sp" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" /> <!-- Description --> </LinearLayout> </androidx.cardview.widget.CardView> <androidx.cardview.widget.CardView android:id="@+id/cardView4" android:layout_width="match_parent" android:layout_height="350dp" android:layout_marginTop="20dp" android:backgroundTint="@android:color/white" android:elevation="8dp" android:radius="12dp" app:cardCornerRadius="12dp" app:cardElevation="8dp" app:cardUseCompatPadding="true"> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:padding="10dp" android:textStyle="bold" android:text="Your date of Birth" android:textColor="#697782" android:textSize="15sp" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" /> <androidx.cardview.widget.CardView android:id="@+id/cardView5" android:layout_width="match_parent" android:layout_height="110dp" android:layout_marginTop="20dp" android:backgroundTint="@android:color/white" android:elevation="8dp" android:radius="12dp" app:cardCornerRadius="12dp" app:cardElevation="8dp" app:cardUseCompatPadding="true"> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="horizontal" android:gravity="center_vertical" android:padding="16dp"> <TextView android:id="@+id/tvCrrente" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text=" Year :- " android:textColor="#899cab" android:textSize="18sp" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" /> <TextView android:id="@+id/tvResult" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Your Age" android:textSize="18sp" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" /> </LinearLayout> </androidx.cardview.widget.CardView> <androidx.cardview.widget.CardView android:id="@+id/cardView6" android:layout_width="match_parent" android:layout_height="110dp" android:layout_marginTop="110dp" android:backgroundTint="@android:color/white" android:elevation="8dp" android:radius="12dp" app:cardCornerRadius="12dp" app:cardElevation="8dp" app:cardUseCompatPadding="true"> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="horizontal" android:gravity="center_vertical" android:padding="16dp"> <TextView android:id="@+id/tvCrrenteerter" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text=" Month :- " android:textColor="#899cab" android:textSize="18sp" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" /> <TextView android:id="@+id/months1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="month" android:textSize="18sp" app:layout_constraintBottom_toTopOf="@id/datePicker" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toTopOf="parent" /> /> </LinearLayout> </androidx.cardview.widget.CardView> <androidx.cardview.widget.CardView android:id="@+id/cardView7" android:layout_width="match_parent" android:layout_height="110dp" android:layout_marginTop="200dp" android:backgroundTint="@android:color/white" android:elevation="8dp" android:radius="12dp" app:cardCornerRadius="12dp" app:cardElevation="8dp" app:cardUseCompatPadding="true"> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="horizontal" android:gravity="center_vertical" android:padding="16dp"> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text=" Day :- " android:textColor="#899cab" android:textSize="18sp" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" /> <TextView android:id="@+id/day1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text=" your total days 06 " android:textColor="#899cab" android:textSize="18sp" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintStart_toStartOf="parent" /> </LinearLayout> </androidx.cardview.widget.CardView> </androidx.cardview.widget.CardView> </LinearLayout> </ScrollView> </LinearLayout>

1. Activity (mainactivity.java)

import androidx.appcompat.app.AppCompatActivity; import androidx.cardview.widget.CardView; import android.annotation.SuppressLint; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.DatePicker; import android.widget.TextView; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Locale; public class MainActivity extends AppCompatActivity { DatePicker datePicker; Button btnCalculate; TextView tvResult, tvCurrentDate, months1 , day1, DOB, Dated; Button selectdate ,clear , Calculate; CardView cardView3 , cardView4; @SuppressLint("MissingInflatedId") @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); datePicker = findViewById(R.id.datePicker); tvResult = findViewById(R.id.tvResult); tvCurrentDate = findViewById(R.id.tvCurrentDate); months1 = findViewById(R.id.months1); selectdate = findViewById(R.id.selectdate); cardView3 =findViewById(R.id.cardView3); day1 = findViewById(R.id.day1); cardView4 = findViewById(R.id.cardView4); clear = findViewById(R.id.clear); DOB = findViewById(R.id.DOB); Dated = findViewById(R.id.Dated); Calculate = findViewById(R.id.Calculate); // Display the current date Calendar today = Calendar.getInstance(); SimpleDateFormat sdf = new SimpleDateFormat("dd MMM yyyy", Locale.getDefault()); String currentDate = sdf.format(today.getTime()); tvCurrentDate.setText("Current Date: " + currentDate); datePicker.setVisibility(View.GONE); cardView3.setVisibility(View.GONE); cardView4.setVisibility(View.GONE); selectdate.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { datePicker.setVisibility(View.VISIBLE); } }); clear.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { datePicker.setVisibility(View.GONE); cardView3.setVisibility(View.GONE); cardView4.setVisibility(View.GONE); } }); // Button Click Listener to calculate age Calculate.setOnClickListener(v -> { int day = datePicker.getDayOfMonth(); int month = datePicker.getMonth(); int year = datePicker.getYear(); int currentYear = today.get(Calendar.YEAR); int currentMonth = today.get(Calendar.MONTH); int currentDay = today.get(Calendar.DAY_OF_MONTH); // Age calculation int age = currentYear - year; int mont = currentMonth - month; int day2 = currentDay - day; if (currentMonth < month || (currentMonth == month && currentDay < day)) { age--; } // Display age result cardView4.setVisibility(View.VISIBLE); cardView3.setVisibility(View.VISIBLE); datePicker.setVisibility(View.GONE); tvResult.setText("Your age is: " + age + " years."); months1.setText("your month " +mont); Dated.setText(" I am currently " + age + "Year old or more precisely 12235325345 second! come to this" + "world on a beautiful Month " +mont ); }); } }