edit ketiga

app/src/main/java/com/example/tiptime/MainActivity.kt

@@ -6,6 +6,7 @@ import androidx.activity.compose.setContent
 import androidx.activity.enableEdgeToEdge
 import androidx.annotation.DrawableRes
 import androidx.annotation.StringRes
+import androidx.compose.foundation.background
 import androidx.compose.foundation.layout.*
 import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.text.KeyboardOptions
@@ -20,11 +21,9 @@ import androidx.compose.ui.text.input.ImeAction
 import androidx.compose.ui.text.input.KeyboardType
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
+import androidx.compose.ui.graphics.Brush
 import com.example.tiptime.ui.theme.TipTimeTheme
 import kotlin.math.pow
-import kotlin.math.roundToInt
-import androidx.compose.foundation.background
-import androidx.compose.ui.graphics.Brush
 
 class MainActivity : ComponentActivity() {
     override fun onCreate(savedInstanceState: Bundle?) {
@@ -44,15 +43,21 @@ class MainActivity : ComponentActivity() {
 fun BmiCalculatorLayout() {
     var heightInput by remember { mutableStateOf("") }
     var weightInput by remember { mutableStateOf("") }
+    var useMetricSystem by remember { mutableStateOf(true) } // ✅ toggle sistem satuan
     var errorMessage by remember { mutableStateOf("") }
-
+    var showResult by remember { mutableStateOf(false) } // ✅ hasil hanya tampil setelah tombol ditekan
-    // State untuk hasil BMI
-    var bmiResult by remember { mutableStateOf<Float?>(null) }
-    var bmiCategory by remember { mutableStateOf("") }
 
     val height = heightInput.toFloatOrNull() ?: 0f
     val weight = weightInput.toFloatOrNull() ?: 0f
-    val isValid = validateInput(height, weight)
+
+    val isValid = validateInput(height, weight, useMetricSystem)
+
+    // Konversi tinggi & berat ke sistem metrik (meter & kg)
+    val heightInMeters = if (useMetricSystem) height / 100f else height * 0.0254f
+    val weightInKg = if (useMetricSystem) weight else weight * 0.453592f
+
+    val bmi = if (isValid && showResult) weightInKg / heightInMeters.pow(2) else 0f
+    val category = if (isValid && showResult) getBMICategory(bmi) else ""
 
     Box(
         modifier = Modifier
@@ -70,6 +75,7 @@ fun BmiCalculatorLayout() {
     ) {
         Column(horizontalAlignment = Alignment.CenterHorizontally) {
 
+            // Judul Aplikasi
             Row(verticalAlignment = Alignment.CenterVertically) {
                 Icon(
                     painter = painterResource(id = R.drawable.ic_launcher_foreground),
@@ -88,6 +94,22 @@ fun BmiCalculatorLayout() {
 
             Spacer(modifier = Modifier.height(24.dp))
 
+            // Toggle Sistem Satuan
+            Row(
+                verticalAlignment = Alignment.CenterVertically,
+                horizontalArrangement = Arrangement.Center
+            ) {
+                Text("SI (kg, cm)")
+                Switch(
+                    checked = !useMetricSystem,
+                    onCheckedChange = { useMetricSystem = !useMetricSystem }
+                )
+                Text("USC (lbs, inci)")
+            }
+
+            Spacer(modifier = Modifier.height(24.dp))
+
+            // Card Input
             Card(
                 elevation = CardDefaults.cardElevation(defaultElevation = 8.dp),
                 colors = CardDefaults.cardColors(
@@ -100,7 +122,7 @@ fun BmiCalculatorLayout() {
                     horizontalAlignment = Alignment.CenterHorizontally
                 ) {
                     EditNumberField(
-                        label = R.string.height,
+                        label = if (useMetricSystem) R.string.height else R.string.height_inch,
                         leadingIcon = R.drawable.number,
                         keyboardOptions = KeyboardOptions(
                             keyboardType = KeyboardType.Number,
@@ -114,7 +136,7 @@ fun BmiCalculatorLayout() {
                     )
 
                     EditNumberField(
-                        label = R.string.weight,
+                        label = if (useMetricSystem) R.string.weight else R.string.weight_lbs,
                         leadingIcon = R.drawable.number,
                         keyboardOptions = KeyboardOptions(
                             keyboardType = KeyboardType.Number,
@@ -129,15 +151,18 @@ fun BmiCalculatorLayout() {
 
             Spacer(modifier = Modifier.height(24.dp))
 
+            // Tombol Hitung BMI
             Button(
                 onClick = {
                     if (!isValid) {
-                        errorMessage = "Masukkan tinggi (20–250 cm) dan berat (10–250 kg) yang valid!"
+                        showResult = false
-                        bmiResult = null
+                        errorMessage = if (useMetricSystem)
+                            "Masukkan tinggi (20–250 cm) dan berat (10–250 kg) yang valid!"
+                        else
+                            "Masukkan tinggi (≥4 inci) dan berat (5–550 lbs) yang valid!"
                     } else {
                         errorMessage = ""
-                        bmiResult = calculateBMI(weight, height)
+                        showResult = true
-                        bmiCategory = getBMICategory(bmiResult!!)
                     }
                 },
                 modifier = Modifier
@@ -145,9 +170,13 @@ fun BmiCalculatorLayout() {
                     .height(56.dp),
                 elevation = ButtonDefaults.elevatedButtonElevation(8.dp)
             ) {
-                Text(text = "Hitung BMI", style = MaterialTheme.typography.titleMedium)
+                Text(
+                    text = "Hitung BMI",
+                    style = MaterialTheme.typography.titleMedium
+                )
             }
 
+            // Pesan error
             if (errorMessage.isNotEmpty()) {
                 Text(
                     text = errorMessage,
@@ -157,9 +186,9 @@ fun BmiCalculatorLayout() {
                 )
             }
 
-            // Tampilkan hasil hanya jika sudah ditekan
+            // Hasil BMI hanya tampil setelah ditekan tombol
-            bmiResult?.let { bmi ->
+            if (showResult && isValid) {
-                val categoryColor = when (bmiCategory) {
+                val categoryColor = when (category) {
                     "Kurus" -> MaterialTheme.colorScheme.tertiaryContainer
                     "Normal" -> MaterialTheme.colorScheme.primaryContainer
                     "Kelebihan Berat" -> MaterialTheme.colorScheme.secondaryContainer
@@ -182,7 +211,7 @@ fun BmiCalculatorLayout() {
                             style = MaterialTheme.typography.titleLarge
                         )
                         Text(
-                            text = "Kategori: $bmiCategory",
+                            text = "Kategori: $category",
                             style = MaterialTheme.typography.bodyLarge
                         )
                     }
@@ -192,11 +221,6 @@ fun BmiCalculatorLayout() {
     }
 }
 
-
-
-/**
- * Fungsi untuk membuat TextField input angka
- */
 @Composable
 fun EditNumberField(
     @StringRes label: Int,
@@ -217,18 +241,6 @@ fun EditNumberField(
     )
 }
 
-/**
- * Menghitung nilai BMI berdasarkan berat (kg) dan tinggi (cm)
- * Rumus: BMI = berat / (tinggi/100)^2
- */
-fun calculateBMI(weight: Float, height: Float): Float {
-    if (height <= 0) return 0f
-    return weight / (height / 100).pow(2)
-}
-
-/**
- * Menentukan kategori BMI
- */
 fun getBMICategory(bmi: Float): String {
     return when {
         bmi < 18.5 -> "Kurus"
@@ -238,11 +250,11 @@ fun getBMICategory(bmi: Float): String {
     }
 }
 
-/**
+fun validateInput(height: Float, weight: Float, useMetric: Boolean): Boolean {
- * Validasi input agar nilai masuk akal
+    return if (useMetric)
- */
+        height in 20f..250f && weight in 10f..250f
-fun validateInput(height: Float, weight: Float): Boolean {
+    else
-    return height in 20f..250f && weight in 10f..250f
+        height >= 4f && height <= 100f && weight in 5f..550f
 }
 
 @Preview(showBackground = true)

app/src/main/res/values/strings.xml

@@ -22,4 +22,6 @@
     <string name="use_usc">Gunakan Unit USC (lbs/in)?</string>
     <string name="bmi_calculation">BMI Anda: %s</string>
     <string name="bmi_category">Kategori: %s</string>
+    <string name="height_inch">Tinggi Badan</string>
+    <string name="weight_lbs">Berat Badan</string>
 </resources>