Currency Converter - 5025211024

Nama : Widian Sasi Disertasiani

NRP : 5025211024

Kelas : PPB D 

Materi : Membuat aplikasi Currency converter

Gambaran: 

Link Youtube: Demo

Github : Code

Berikut adalah codenya:

package com.example.currencyconverter

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.activity.enableEdgeToEdge
import androidx.compose.animation.AnimatedVisibility
import androidx.compose.animation.fadeIn
import androidx.compose.animation.fadeOut
import androidx.compose.foundation.background
import androidx.compose.foundation.clickable
import androidx.compose.foundation.interaction.MutableInteractionSource
import androidx.compose.foundation.interaction.collectIsPressedAsState
import androidx.compose.foundation.layout.*
import androidx.compose.foundation.text.KeyboardOptions
import androidx.compose.material.icons.Icons
import androidx.compose.material.icons.filled.ArrowDropDown
import androidx.compose.material3.*
import androidx.compose.runtime.*
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.text.input.KeyboardType
import androidx.compose.ui.unit.dp
import androidx.compose.ui.unit.sp
import com.example.currencyconverter.ui.theme.CurrencyConverterTheme

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        enableEdgeToEdge()
        setContent {
            CurrencyConverterTheme {
                Surface(
                    modifier = Modifier.fillMaxSize(),
                    color = Color.White
                ) {
                    SimpleCurrencyConverter()
                }
            }
        }
    }
}

@Composable
fun SimpleCurrencyConverter() {
    var amount by remember { mutableStateOf("") }
    var fromCurrency by remember { mutableStateOf("USD") }
    var toCurrency by remember { mutableStateOf("Indonesia (IDR)") }
    var fromExpanded by remember { mutableStateOf(false) }
    var toExpanded by remember { mutableStateOf(false) }
    var showResult by remember { mutableStateOf(false) }

    val currencyMap = mapOf(
        "USD" to "USD",
        "Indonesia (IDR)" to "IDR",
        "Algeria (DZD)" to "DZD",
        "Brazil (BRL)" to "BRL",
        "Japan (JPY)" to "JPY",
        "Europe (EUR)" to "EUR"
    )

    val exchangeRates = mapOf(
        Pair("USD", "IDR") to 16800.0,
        Pair("USD", "DZD") to 134.4,
        Pair("USD", "BRL") to 5.12,
        Pair("USD", "JPY") to 151.0,
        Pair("USD", "EUR") to 0.91
    )

    var converted by remember { mutableStateOf(0.0) }

    Column(
        modifier = Modifier
            .fillMaxSize()
            .padding(24.dp),
        verticalArrangement = Arrangement.spacedBy(16.dp)
    ) {
        Row(modifier = Modifier.fillMaxWidth(), horizontalArrangement = Arrangement.End) {
            Text("Contact", color = Color(0xFF00C8A0))
        }

        Text("Currency", fontSize = 28.sp, color = Color(0xFF005BFF))
        Text("Converter", fontSize = 28.sp, color = Color(0xFF005BFF))

        // From Dropdown
        Text("From")
        DropdownSelector(
            selected = fromCurrency,
            options = currencyMap.keys.toList(),
            expanded = fromExpanded,
            onExpandedChange = { fromExpanded = it },
            onSelect = { fromCurrency = it }
        )

        // To Dropdown
        Text("To")
        DropdownSelector(
            selected = toCurrency,
            options = currencyMap.keys.toList(),
            expanded = toExpanded,
            onExpandedChange = { toExpanded = it },
            onSelect = { toCurrency = it }
        )

        OutlinedTextField(
            value = amount,
            onValueChange = { amount = it },
            label = { Text("Amount in ${currencyMap[fromCurrency]}") },
            keyboardOptions = KeyboardOptions.Default.copy(keyboardType = KeyboardType.Number),
            modifier = Modifier.fillMaxWidth()
        )

        val buttonInteractionSource = remember { MutableInteractionSource() }
        val buttonPressed by buttonInteractionSource.collectIsPressedAsState()

        Button(
            onClick = {
                val rate = exchangeRates[Pair(fromCurrency, currencyMap[toCurrency])] ?: 1.0
                converted = amount.toDoubleOrNull()?.times(rate) ?: 0.0
                showResult = true
            },
            modifier = Modifier
                .fillMaxWidth()
                .height(50.dp),
            colors = ButtonDefaults.buttonColors(
                containerColor = if (buttonPressed) Color(0xFF009e82) else Color(0xFF00C8A0)
            ),
            interactionSource = buttonInteractionSource
        ) {
            Text("Convert", color = Color.White)
        }

        AnimatedVisibility(visible = showResult, enter = fadeIn(), exit = fadeOut()) {
            Column {
                Text("Result", fontSize = 16.sp)
                Text(
                    text = "%.2f %s".format(converted, currencyMap[toCurrency] ?: ""),
                    fontSize = 18.sp
                )
            }
        }
    }
}

@Composable
fun DropdownSelector(
    selected: String,
    options: List<String>,
    expanded: Boolean,
    onExpandedChange: (Boolean) -> Unit,
    onSelect: (String) -> Unit
) {
    val interactionSource = remember { MutableInteractionSource() }
    val isPressed by interactionSource.collectIsPressedAsState()

    Box {
        OutlinedTextField(
            value = selected,
            onValueChange = {},
            readOnly = true,
            modifier = Modifier
                .fillMaxWidth()
                .background(if (isPressed) Color(0xFFF0F0F0) else Color.Transparent),
            trailingIcon = {
                Icon(Icons.Default.ArrowDropDown, contentDescription = null)
            },
            interactionSource = interactionSource
        )

        DropdownMenu(
            expanded = expanded,
            onDismissRequest = { onExpandedChange(false) }
        ) {
            options.forEach {
                DropdownMenuItem(
                    text = { Text(it) },
                    onClick = {
                        onSelect(it)
                        onExpandedChange(false)
                    }
                )
            }
        }

        Spacer(
            modifier = Modifier
                .matchParentSize()
                .clickable { onExpandedChange(true) }
        )
    }
}