Design and develop any converter application currency converter.

A Currency Converter App helps users convert currencies like USD, INR, EUR, etc., using predefined or real-time exchange rates. This project demonstrates Android UI design and basic calculation logic.

🎯 Objective

• Convert one currency to another
• Provide a simple UI for users
• Perform quick calculations
• Learn Android development basics

🛠️ Technologies Used

• Android Studio
• Java
• XML (UI Design)

📱 Application Features

• Easy input for amount
• Currency selection (basic version)
• Instant conversion
• Simple and clean UI

🖥️ Step 1: Design Layout (XML)

Here is the UI design for the Currency Converter App:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:padding="20dp">

<EditText
    android:id="@+id/etName"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:hint="Enter Name"/>

<Button
    android:id="@+id/btnInsert"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="Insert"/>

<Button
    android:id="@+id/btnView"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="View"/>

<Button
    android:id="@+id/btnUpdate"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="Update"/>

<Button
    android:id="@+id/btnDelete"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="Delete"/>

</LinearLayout>

⚙️ Step 2: Java Code (MainActivity)

This code handles the conversion logic:

package com.example.databasedemo;

import android.content.ContentValues;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

public class DatabaseHelper extends SQLiteOpenHelper {

    public static final String DB_NAME="StudentDB";
    public static final String TABLE_NAME="student";

    public DatabaseHelper(Context context){
        super(context,DB_NAME,null,1);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("CREATE TABLE student(id INTEGER PRIMARY KEY AUTOINCREMENT,name TEXT)");
    }

    @Override
    public void onUpgrade(SQLiteDatabase db,int oldVersion,int newVersion){
        db.execSQL("DROP TABLE IF EXISTS student");
        onCreate(db);
    }

    public boolean insertData(String name){
        SQLiteDatabase db=this.getWritableDatabase();
        ContentValues cv=new ContentValues();
        cv.put("name",name);
        long result=db.insert(TABLE_NAME,null,cv);
        return result!=-1;
    }
}

🧠 Working Explanation

• User enters amount
• Selects currencies
• Clicks convert button
• App calculates using predefined rates
• Result is displayed instantly

🚀 Future Improvements

• 🌐 Add real-time API integration
• 🔄 Add currency swap feature
• 📊 Show exchange rate history
• 📱 Improve UI with Material Design