A Jetpack Compose (Android Desktop) modifier enabling reordering by drag and drop in a LazyList and LazyGrid.
dependencies {
implementation("org.burnoutcrew.composereorderable:reorderable:<latest_version>")
}
- Create a reorderable state by
rememberReorderableLazyListState
for LazyList orrememberReorderableLazyGridState
for LazyGrid - Add the
reorderable(state)
modifier to your list/grid - Inside the list/grid itemscope create a
ReorderableItem(state, key = )
for a keyed lists orReorderableItem(state, index = )
for a indexed only list. (Animated items only work with keyed lists) - Apply the
detectReorderAfterLongPress(state)
ordetectReorder(state)
modifier to the list. If only a drag handle is needed apply the detect modifier to any child composable inside the item layout.
ReorderableItem
provides the item dragging state, use this to apply elevation , scale etc.
@Composable
fun VerticalReorderList() {
val data = remember { mutableStateOf(List(100) { "Item $it" }) }
val state = rememberReorderableLazyListState(onMove = { from, to ->
data.value = data.value.toMutableList().apply {
add(to.index, removeAt(from.index))
}
})
LazyColumn(
state = state.listState,
modifier = Modifier
.reorderable(state)
.detectReorderAfterLongPress(state)
) {
items(data.value, { it }) { item ->
ReorderableItem(state, key = item) { isDragging ->
val elevation = animateDpAsState(if (isDragging) 16.dp else 0.dp)
Column(
modifier = Modifier
.shadow(elevation.value)
.background(MaterialTheme.colors.surface)
) {
Text(item)
}
}
}
}
}
The item placement and drag cancelled animation can be changed or disabled by dragCancelledAnimation
and defaultDraggingModifier
@Composable
fun VerticalReorderGrid() {
val data = remember { mutableStateOf(List(100) { "Item $it" }) }
val state = rememberReorderableLazyGridState(dragCancelledAnimation = NoDragCancelledAnimation(),
onMove = { from, to ->
data.value = data.value.toMutableList().apply {
add(to.index, removeAt(from.index))
}
})
LazyVerticalGrid(
columns = GridCells.Fixed(4),
state = state.gridState,
modifier = Modifier.reorderable(state)
) {
items(data.value, { it }) { item ->
ReorderableItem(state, key = item, defaultDraggingModifier = Modifier) { isDragging ->
Box(
modifier = Modifier
.aspectRatio(1f)
.background(MaterialTheme.colors.surface)
) {
Text(text = item,
modifier = Modifier.detectReorderAfterLongPress(state)
)
}
}
}
}
}
Check out the sample app for different implementation samples.
It's a known issue that the first visible item does not animate.
Copyright 2021 André Claßen
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
https://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.