Currency Converter App in Flutter

This tutorial will teach you how to make make a Currency Converter App in Flutter step by step.it will help you convert the currency easily.

Main.dart

import 'package:currency_converter/currect_converter.dart';
import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      debugShowCheckedModeBanner: false,
      theme: ThemeData(

        primarySwatch: Colors.blue,
      ),
      home: CurrecyConverter(),
    );
  }
}

currect_converter.dart


import 'package:flutter/material.dart';

class CurrecyConverter extends StatefulWidget {
  const CurrecyConverter({ Key key }) : super(key: key);

  @override
  State<CurrecyConverter> createState() => _CurrecyConverterState();
}

class _CurrecyConverterState extends State<CurrecyConverter> {
  String valueschoose;
  String valueschoose1;
  @override
  Widget build(BuildContext context) {

      final _amount = TextEditingController();
      final _tot = TextEditingController();
      int cal;
      int result;

var size = MediaQuery.of(context).size;

    return Scaffold(
      body: SafeArea(
        child: Container(
          padding:EdgeInsets.symmetric(horizontal: 15,vertical: 20),
          child: Column(
            children: [
                Text("Currency Converter",style: TextStyle(fontSize: 30, color: Colors.black)),
                SizedBox(height: 15,),
                  TextField(
                           controller: _amount,
                           decoration: InputDecoration(
                             labelText: "Amount",
                             labelStyle: TextStyle(fontSize: 15,color: Colors.grey.shade400),
                             border: OutlineInputBorder(borderRadius: BorderRadius.circular(10))
                           ),
                ),
                SizedBox(height: 15,),
                 DropdownButton<String>(
                      
                    value: this.valueschoose,
                      items: <String>['Srilankan Rupees', 'Indian Rupees'].map((String value) {
                        return DropdownMenuItem<String>(
                          value: value,
                          child: Text(value),
                        );
                      }).toList(),
                      onChanged: (value) => setState(() => this.valueschoose = value,
    
                    )),

                     SizedBox(height: 15,),

              DropdownButton<String>(
                     value: this.valueschoose1,
                      items: <String>['USD'].map((String value) {
                        return DropdownMenuItem<String>(
                          value: value,
                          child: Text(value),
                        );
                      }).toList(),
                      onChanged: (value) => setState(() => this.valueschoose1 = value,
    
                    )),
              SizedBox(height: 15,),

               TextField(
                           controller: _tot,
                           decoration: InputDecoration(
                             labelText: "Total",
                             labelStyle: TextStyle(fontSize: 15,color: Colors.grey.shade400),
                             border: OutlineInputBorder(borderRadius: BorderRadius.circular(10))
                           ),
                ),
              SizedBox(height: 15,),

                   GestureDetector(
                     
                
             onTap: ()
             {
                if(valueschoose=="Srilankan Rupees" && valueschoose1=="USD")
                {
                     
                    cal =  int.parse(_amount.text) * 300; 
                    result = cal;
                   _tot.text = result.toString();
                }
                else if(valueschoose=="Indian Rupees" && valueschoose1=="USD")
                {
                    cal =  int.parse(_amount.text) * 78; 
                    result = cal;
                   _tot.text = result.toString(); 

                }


              },




                     child: Container(
                       alignment: Alignment.center,
                       height: size.height / 14,
                        width: size.width,
                      
                        decoration: BoxDecoration(color: Colors.red,
                            borderRadius: BorderRadius.circular(5)), 
                       
                       child: Text("Convert", 
                                  style: TextStyle(color: Colors.white,
                                  fontWeight: FontWeight.bold),),
                     ),
                   )
       

            ],
          ),
        ),
      ),
    );
  }
}