🔀 :: (#705) 외출 신청 디자인 수정

🔀 :: (#705) 외출 신청 디자인 수정

core/design-system/src/main/java/team/aliens/dms/android/core/designsystem/Picker.kt

@@ -0,0 +1,115 @@
+package team.aliens.dms.android.core.designsystem
+
+import androidx.compose.foundation.ExperimentalFoundationApi
+import androidx.compose.foundation.gestures.snapping.rememberSnapFlingBehavior
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.rememberLazyListState
+import androidx.compose.material3.LocalContentColor
+import androidx.compose.material3.LocalTextStyle
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableIntStateOf
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.runtime.snapshotFlow
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.drawWithContent
+import androidx.compose.ui.graphics.BlendMode
+import androidx.compose.ui.graphics.Brush
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.CompositingStrategy
+import androidx.compose.ui.graphics.graphicsLayer
+import androidx.compose.ui.layout.onSizeChanged
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.text.TextStyle
+import androidx.compose.ui.text.style.TextOverflow
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.map
+
+@OptIn(ExperimentalFoundationApi::class)
+@Composable
+fun Picker(
+ items: List<String>,
+ state: PickerState = rememberPickerState(),
+ modifier: Modifier = Modifier,
+ startIndex: Int = 0,
+ visibleItemsCount: Int = 3,
+ textModifier: Modifier = Modifier,
+ textStyle: TextStyle = LocalTextStyle.current,
+) {
+ val visibleItemsMiddle = visibleItemsCount / 2
+ val listScrollCount = Integer.MAX_VALUE
+ val listScrollMiddle = listScrollCount / 2
+ val listStartIndex = listScrollMiddle - listScrollMiddle % items.size - visibleItemsMiddle + startIndex
+
+ fun getItem(index: Int) = items[index % items.size]
+
+ val listState = rememberLazyListState(initialFirstVisibleItemIndex = listStartIndex)
+ val flingBehavior = rememberSnapFlingBehavior(lazyListState = listState)
+
+ val itemHeightPixels = remember { mutableIntStateOf(0) }
+ val itemHeightDp = pixelsToDp(itemHeightPixels.value)
+
+ val fadingEdgeGradient = remember {
+ Brush.verticalGradient(
+ 0f to Color.Transparent,
+ 0.5f to Color.Black,
+ 1f to Color.Transparent
+ )
+ }
+
+ LaunchedEffect(listState) {
+ snapshotFlow { listState.firstVisibleItemIndex }
+ .map { index -> getItem(index + visibleItemsMiddle) }
+ .distinctUntilChanged()
+ .collect { item -> state.selectedItem = item }
+ }
+
+ Box(modifier = modifier) {
+ LazyColumn(
+ state = listState,
+ flingBehavior = flingBehavior,
+ horizontalAlignment = Alignment.CenterHorizontally,
+ modifier = Modifier
+ .fillMaxWidth()
+ .height(itemHeightDp * visibleItemsCount)
+ .fadingEdge(fadingEdgeGradient)
+ ) {
+ items(listScrollCount) { index ->
+ Text(
+ text = getItem(index),
+ maxLines = 1,
+ overflow = TextOverflow.Ellipsis,
+ style = textStyle,
+ modifier = Modifier
+ .onSizeChanged { size -> itemHeightPixels.value = size.height }
+ .then(textModifier)
+ )
+ }
+ }
+ }
+}
+
+private fun Modifier.fadingEdge(brush: Brush) = this
+ .graphicsLayer(compositingStrategy = CompositingStrategy.Offscreen)
+ .drawWithContent {
+ drawContent()
+ drawRect(brush = brush, blendMode = BlendMode.DstIn)
+ }
+
+@Composable
+private fun pixelsToDp(pixels: Int) = with(LocalDensity.current) { pixels.toDp() }
+
+@Composable
+fun rememberPickerState() = remember { PickerState() }
+
+class PickerState {
+ var selectedItem by mutableStateOf("")
+}