Tugas 7 Currency Converter

 Nama : Mohammad Ahnaf Fauzan

NRP: 5025211170

Currency Converter

Pada pertemuan ke 7 ini kami diminta untuk membuat aplikasi currency converter. Pada aplikasi  ini kami diminta setidaknya dapat mengkonversi 10 mata uang. Berikut kode yang sudah dihasilkan:

package com.example.currencyconverter

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.foundation.layout.*
import androidx.compose.foundation.text.KeyboardOptions
import androidx.compose.material3.*
import androidx.compose.runtime.*
import androidx.compose.ui.Modifier
import androidx.compose.ui.text.input.KeyboardType
import androidx.compose.ui.unit.dp
import androidx.compose.foundation.clickable

import com.example.currencyconverter.ui.theme.CurrencyConverterTheme

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            CurrencyConverterTheme {
                Surface(modifier = Modifier.fillMaxSize()) {
                    CurrencyConverterScreen()
                }
            }
        }
    }
}

@Composable
fun CurrencyConverterScreen() {
    val currencies = listOf("USD", "EUR", "IDR", "JPY", "GBP", "AUD", "CAD", "CHF", "CNY", "SGD")

    val exchangeRates = mapOf(
        "USD" to 1.0,
        "EUR" to 0.94,
        "IDR" to 15900.0,
        "JPY" to 154.0,
        "GBP" to 0.80,
        "AUD" to 1.52,
        "CAD" to 1.36,
        "CHF" to 0.91,
        "CNY" to 7.2,
        "SGD" to 1.35
    )

    var amountInput by remember { mutableStateOf("") }
    var fromCurrency by remember { mutableStateOf("USD") }
    var toCurrency by remember { mutableStateOf("IDR") }
    var result by remember { mutableStateOf("") }

    Column(modifier = Modifier
        .fillMaxSize()
        .padding(16.dp),
        verticalArrangement = Arrangement.spacedBy(12.dp)
    ) {
        OutlinedTextField(
            value = amountInput,
            onValueChange = { amountInput = it },
            label = { Text("Amount") },
            keyboardOptions = KeyboardOptions.Default.copy(keyboardType = KeyboardType.Number),
            modifier = Modifier.fillMaxWidth()
        )

        CurrencyDropdown(label = "From", selectedCurrency = fromCurrency, currencies = currencies) {
            fromCurrency = it
        }

        CurrencyDropdown(label = "To", selectedCurrency = toCurrency, currencies = currencies) {
            toCurrency = it
        }

        Button(
            onClick = {
                val amount = amountInput.toDoubleOrNull()
                if (amount != null) {
                    val usdAmount = amount / exchangeRates[fromCurrency]!!
                    val converted = usdAmount * exchangeRates[toCurrency]!!
                    result = "%.2f $fromCurrency = %.2f $toCurrency".format(amount, converted)
                } else {
                    result = "Invalid input"
                }
            },
            modifier = Modifier.fillMaxWidth()
        ) {
            Text("Convert")
        }

        Text(
            text = result,
            style = MaterialTheme.typography.bodyLarge
        )
    }
}

@Composable
fun CurrencyDropdown(
    label: String,
    selectedCurrency: String,
    currencies: List<String>,
    onCurrencySelected: (String) -> Unit
) {
    var expanded by remember { mutableStateOf(false) }

    Column {
        Text(label)
        Box {
            OutlinedTextField(
                value = selectedCurrency,
                onValueChange = {},
                readOnly = true,
                modifier = Modifier.fillMaxWidth(),
                label = { Text(label) }
            )
            DropdownMenu(
                expanded = expanded,
                onDismissRequest = { expanded = false }
            ) {
                currencies.forEach { currency ->
                    DropdownMenuItem(
                        text = { Text(currency) },
                        onClick = {
                            onCurrencySelected(currency)
                            expanded = false
                        }
                    )
                }
            }

            Spacer(
                modifier = Modifier
                    .matchParentSize()
                    .padding(8.dp)
                    .clickable { expanded = true }
            )
        }
    }
}

Adapun pada aplikasi ini, kita bisa melakukan input untuk jumlah uang yang ingin dihitung, kemudian disediakan juga pilihan mata uang yang ingin dihitung. Berikut merupakan tampilan dari aplikasi ini:

Setelah melakukan input dari jumlah, kemudian mata uang yang ingin dikonversi, maka selanjutnya kita dapat menekan tombol convert untuk mengerluarkan hasil konversi.