[feat] #20 date picker 구현 완료

app/src/main/java/org/android/bbangzip/presentation/component/wheelpicker/BbangZipDatePicker.kt

@@ -5,65 +5,94 @@ import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.padding
+import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.derivedStateOf
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
+import org.android.bbangzip.presentation.model.Date
+import org.android.bbangzip.presentation.util.constant.DateConstant
 import java.time.YearMonth
 
 @Composable
-fun BbangZipDatePicker() {
+fun BbangZipDatePicker(
+    onConfirm: (Date) -> Unit = {},
+    currentDate: Date = Date(DateConstant.YEAR_OF_TODAY.toString(), "1", "1"),
+) {
     Row(
         modifier = Modifier.fillMaxWidth(),
     ) {
-        val years = (2025..2035).map { it.toString() + "년" }
+        val years = DateConstant.YEARS_LIST
         val yearPickerState = rememberPickerState()
+        val startYear = currentDate.year.toInt() - DateConstant.YEAR_OF_TODAY
 
-        val months = (1..12).map { it.toString() + "월" }
+        val months = DateConstant.MONTHS_LIST
         val monthsPickerState = rememberPickerState()
+        val startMonth = currentDate.month.toInt() - 1
 
         val days =
             remember(yearPickerState.selectedItem, monthsPickerState.selectedItem) {
                 derivedStateOf {
-                    val year = yearPickerState.selectedItem.filter { it.isDigit() }.toIntOrNull() ?: 2025
+                    val year = yearPickerState.selectedItem.filter { it.isDigit() }.toIntOrNull() ?: DateConstant.YEAR_OF_TODAY
                     val month = monthsPickerState.selectedItem.filter { it.isDigit() }.toIntOrNull() ?: 1
                     (1..getDaysInMonth(year, month)).map { it.toString() + "일" }
                 }
             }
         val daysPickerState = rememberPickerState()
+        val startDay = currentDate.day.toInt() - 1
+
+        LaunchedEffect(yearPickerState.selectedItem, monthsPickerState.selectedItem, daysPickerState.selectedItem) {
+            val year = yearPickerState.selectedItem.filter { it.isDigit() }
+            val month = monthsPickerState.selectedItem.filter { it.isDigit() }
+            val day = daysPickerState.selectedItem.filter { it.isDigit() }
+            onConfirm(
+                Date(
+                    year = year,
+                    month = month,
+                    day = day
+                )
+            )
+        }
 
         Picker(
             state = yearPickerState,
             items = years,
-            visibleItemsCount = 5,
             modifier = Modifier.weight(0.4f),
+            startIndex = startYear,
+            visibleItemsCount = 5,
             textModifier = Modifier.padding(8.dp),
-            isCircular = true,
+            isCircular = false,
         )
 
         Picker(
             state = monthsPickerState,
             items = months,
-            visibleItemsCount = 5,
             modifier = Modifier.weight(0.3f),
+            startIndex = startMonth,
+            visibleItemsCount = 5,
             textModifier = Modifier.padding(8.dp),
-            isCircular = true,
+            isCircular = false,
         )
 
         Picker(
             state = daysPickerState,
             items = days.value,
-            startIndex = 0, // if(daysPickerState.selectedItem == "") daysPickerState.selectedItem.toInt() else 0,
+            startIndex = startDay,
             visibleItemsCount = 5,
             modifier = Modifier.weight(0.3f),
             textModifier = Modifier.padding(8.dp),
-            isCircular = true,
+            isCircular = false,
         )
     }
 }
 
+// 현재 달이 몇일 있는 지 알아낼 함수, 어디로 빼야할까요?
 fun getDaysInMonth(
     year: Int,
     month: Int,
@@ -74,12 +103,20 @@ fun getDaysInMonth(
 @Preview(showBackground = true)
 @Composable
 fun BbangZipDatePickerPreview() {
+    var selectedDate by remember { mutableStateOf<Date?>(null) }
+
     Column(
         modifier =
-            Modifier
-                .fillMaxSize()
-                .padding(16.dp),
+        Modifier
+            .fillMaxSize()
+            .padding(16.dp),
     ) {
-        BbangZipDatePicker()
+        BbangZipDatePicker(
+            onConfirm = {
+                selectedDate = it
+            },
+            currentDate = Date("2026", "3", "16"),
+        )
+        Text("Selected Date: ${selectedDate?.year}년 ${selectedDate?.month}월 ${selectedDate?.day}일")
     }
 }

app/src/main/java/org/android/bbangzip/presentation/component/wheelpicker/BbangZipPicker.kt

@@ -70,7 +70,7 @@ fun Picker(
         if (isCircular) {
             listScrollMiddle - listScrollMiddle % pickerItems.size - visibleItemsMiddle + startIndex
         } else {
-            0 // isCircular가 false이면 시작 인덱스를 0으로 설정
+            0 + startIndex // isCircular가 false이면 시작 인덱스를 0으로 설정
         }
 
     fun getItem(index: Int) = pickerItems[index % pickerItems.size]

app/src/main/java/org/android/bbangzip/presentation/model/Date.kt

@@ -0,0 +1,11 @@
+package org.android.bbangzip.presentation.model
+
+import android.os.Parcelable
+import kotlinx.parcelize.Parcelize
+
+@Parcelize
+data class Date(
+    val year: String,
+    val month: String,
+    val day: String,
+) : Parcelable

app/src/main/java/org/android/bbangzip/presentation/util/constant/DateConstant.kt

@@ -1,5 +1,10 @@
 package org.android.bbangzip.presentation.util.constant
 
+import java.time.LocalDate
+
 object DateConstant {
+    const val YEAR_OF_TODAY = 2025
 
+    val YEARS_LIST = (YEAR_OF_TODAY..2099).map { it.toString() + "년" }
+    val MONTHS_LIST = (1..12).map { it.toString() + "월" }
 }