v0.2.9: True Touch Drag & Drop Reordering & Fix OTA Auto-Install Bug

app/src/main/java/com/hotdeal/alarm/presentation/components/DragDropListState.kt

@@ -0,0 +1,138 @@
+package com.hotdeal.alarm.presentation.components
+
+import androidx.compose.animation.core.Animatable
+import androidx.compose.animation.core.Spring
+import androidx.compose.animation.core.spring
+import androidx.compose.foundation.gestures.detectDragGesturesAfterLongPress
+import androidx.compose.foundation.gestures.scrollBy
+import androidx.compose.foundation.lazy.LazyListItemInfo
+import androidx.compose.foundation.lazy.LazyListState
+import androidx.compose.runtime.*
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.graphics.graphicsLayer
+import androidx.compose.ui.input.pointer.pointerInput
+import androidx.compose.ui.zIndex
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.launch
+
+/**
+ * Compose LazyColumn Drag & Drop Reordering State
+ */
+@Composable
+fun rememberDragDropListState(
+    lazyListState: LazyListState,
+    onMove: (Int, Int) -> Unit,
+    onDragEnd: () -> Unit = {}
+): DragDropListState {
+    val scope = rememberCoroutineScope()
+    val state = remember(lazyListState) {
+        DragDropListState(
+            lazyListState = lazyListState,
+            onMove = onMove,
+            onDragEnd = onDragEnd,
+            scope = scope
+        )
+    }
+    return state
+}
+
+class DragDropListState(
+    val lazyListState: LazyListState,
+    private val onMove: (Int, Int) -> Unit,
+    private val onDragEnd: () -> Unit,
+    private val scope: CoroutineScope
+) {
+    var initiallyDraggedElement by mutableStateOf<LazyListItemInfo?>(null)
+        private set
+
+    var currentIndexOfDraggedItem by mutableStateOf<Int?>(null)
+        private set
+
+    private val dragOffset = Animatable(0f)
+
+    val elementOffset: Float
+        get() = dragOffset.value
+
+    fun onDragStart(offset: Offset) {
+        lazyListState.layoutInfo.visibleItemsInfo
+            .firstOrNull { item -> offset.y.toInt() in item.offset..(item.offset + item.size) }
+            ?.also { item ->
+                currentIndexOfDraggedItem = item.index
+                initiallyDraggedElement = item
+            }
+    }
+
+    fun onDragInterrupted() {
+        initiallyDraggedElement = null
+        currentIndexOfDraggedItem = null
+        scope.launch {
+            dragOffset.snapTo(0f)
+        }
+    }
+
+    fun onDrag(change: Offset) {
+        scope.launch {
+            dragOffset.snapTo(dragOffset.value + change.y)
+
+            val currentElement = initiallyDraggedElement ?: return@launch
+            val startOffset = currentElement.offset + dragOffset.value
+            val endOffset = startOffset + currentElement.size
+
+            val hoveredItem = lazyListState.layoutInfo.visibleItemsInfo
+                .firstOrNull { item ->
+                    val itemMid = item.offset + item.size / 2
+                    val isMidInRange = itemMid in startOffset.toInt()..endOffset.toInt()
+                    isMidInRange && item.index != currentIndexOfDraggedItem
+                }
+
+            if (hoveredItem != null) {
+                val currentIndex = currentIndexOfDraggedItem ?: return@launch
+                val targetIndex = hoveredItem.index
+                onMove(currentIndex, targetIndex)
+                currentIndexOfDraggedItem = targetIndex
+            }
+        }
+    }
+
+    fun onDragStop() {
+        onDragEnd()
+        scope.launch {
+            dragOffset.animateTo(0f, spring(stiffness = Spring.StiffnessMediumLow))
+            initiallyDraggedElement = null
+            currentIndexOfDraggedItem = null
+        }
+    }
+}
+
+fun Modifier.dragDropGesture(
+    dragDropState: DragDropListState
+): Modifier = this.pointerInput(dragDropState) {
+    detectDragGesturesAfterLongPress(
+        onDragStart = { offset -> dragDropState.onDragStart(offset) },
+        onDragEnd = { dragDropState.onDragStop() },
+        onDragCancel = { dragDropState.onDragInterrupted() },
+        onDrag = { change, dragAmount ->
+            change.consume()
+            dragDropState.onDrag(dragAmount)
+        }
+    )
+}
+
+fun Modifier.dragDropItem(
+    index: Int,
+    dragDropState: DragDropListState
+): Modifier = this.then(
+    if (index == dragDropState.currentIndexOfDraggedItem) {
+        Modifier
+            .zIndex(10f)
+            .graphicsLayer {
+                translationY = dragDropState.elementOffset
+                scaleX = 1.03f
+                scaleY = 1.03f
+                shadowElevation = 8f
+            }
+    } else {
+        Modifier
+    }
+)