Develop Reference

Jetpack Compose: How to create multi-item FAB with animation?

I'm trying to create a multi-item floating action button with the following animation:
I created a multi-item floating action button but I could not implement the intended animation.
I have FilterFabMenuButton composable that I show as a menu item :
FilterFabMenuButton
#Composable
fun FilterFabMenuButton(
item: FilterFabMenuItem,
onClick: (FilterFabMenuItem) -> Unit,
modifier: Modifier = Modifier
) {
FloatingActionButton(
modifier = modifier,
onClick = {
onClick(item)
},
backgroundColor = colorResource(
id = R.color.primary_color
)
) {
Icon(
painter = painterResource(item.icon), contentDescription = null, tint = colorResource(
id = R.color.white
)
)
}
}
I have FilterFabMenuLabel composable which is a label for FilterFabMenuButton:
FilterFabMenuLabel
#Composable
fun FilterFabMenuLabel(
label: String,
modifier: Modifier = Modifier
) {
Surface(
modifier = modifier,
shape = RoundedCornerShape(6.dp),
color = Color.Black.copy(alpha = 0.8f)
) {
Text(
text = label, color = Color.White,
modifier = Modifier.padding(horizontal = 20.dp, vertical = 2.dp),
fontSize = 14.sp,
maxLines = 1
)
}
}
I have FilterFabMenuItem composable which is a Row that contains FilterFabMenuLabel and FilterFabMenuButton composables:
FilterFabMenuItem
#Composable
fun FilterFabMenuItem(
menuItem: FilterFabMenuItem,
onMenuItemClick: (FilterFabMenuItem) -> Unit,
modifier: Modifier = Modifier
) {
Row(
modifier = modifier,
horizontalArrangement = Arrangement.spacedBy(10.dp),
verticalAlignment = Alignment.CenterVertically
) {
//label
FilterFabMenuLabel(label = menuItem.label)
//fab
FilterFabMenuButton(item = menuItem, onClick = onMenuItemClick)
}
}
I have FilterFabMenu composable which is a Column that shows menu items:
FilterFabMenu
#Composable
fun FilterFabMenu(
visible: Boolean,
items: List<FilterFabMenuItem>,
modifier: Modifier = Modifier
) {
val enterTransition = remember {
expandVertically(
expandFrom = Alignment.Bottom,
animationSpec = tween(150, easing = FastOutSlowInEasing)
) + fadeIn(
initialAlpha = 0.3f,
animationSpec = tween(150, easing = FastOutSlowInEasing)
)
}
val exitTransition = remember {
shrinkVertically(
shrinkTowards = Alignment.Bottom,
animationSpec = tween(150, easing = FastOutSlowInEasing)
) + fadeOut(
animationSpec = tween(150, easing = FastOutSlowInEasing)
)
}
AnimatedVisibility(visible = visible, enter = enterTransition, exit = exitTransition) {
Column(
modifier = modifier.fillMaxWidth(), horizontalAlignment = Alignment.End,
verticalArrangement = Arrangement.spacedBy(16.dp),
) {
items.forEach { menuItem ->
FilterFabMenuItem(
menuItem = menuItem,
onMenuItemClick = {}
)
}
}
}
}
I have FilterFab composable that expands/collapses FilterMenu:
FilterFab
#Composable
fun FilterFab(
state: FilterFabState,
rotation:Float,
onClick: (FilterFabState) -> Unit,
modifier: Modifier = Modifier
) {
FloatingActionButton(
modifier = modifier
.rotate(rotation),
elevation = FloatingActionButtonDefaults.elevation(defaultElevation = 0.dp),
onClick = {
onClick(
if (state == FilterFabState.EXPANDED) {
FilterFabState.COLLAPSED
} else {
FilterFabState.EXPANDED
}
)
},
backgroundColor = colorResource(
R.color.primary_color
),
shape = CircleShape
) {
Icon(
painter = painterResource(R.drawable.fab_add),
contentDescription = null,
tint = Color.White
)
}
}
Last but not least, I have a FilterView composable which is a Column that contains FilterFabMenu and FilterFab composables:
FilterView
#SuppressLint("UnusedTransitionTargetStateParameter")
#Composable
fun FilterView(
items: List<FilterFabMenuItem>,
modifier: Modifier = Modifier
) {
var filterFabState by rememberSaveable() {
mutableStateOf(FilterFabState.COLLAPSED)
}
val transitionState = remember {
MutableTransitionState(filterFabState).apply {
targetState = FilterFabState.COLLAPSED
}
}
val transition = updateTransition(targetState = transitionState, label = "transition")
val iconRotationDegree by transition.animateFloat({
tween(durationMillis = 150, easing = FastOutSlowInEasing)
}, label = "rotation") {
if (filterFabState == FilterFabState.EXPANDED) 230f else 0f
}
Column(
modifier = modifier.fillMaxSize().padding(16.dp), horizontalAlignment = Alignment.End,
verticalArrangement = Arrangement.spacedBy(16.dp,Alignment.Bottom)
) {
FilterFabMenu(items = items, visible = filterFabState == FilterFabState.EXPANDED)
FilterFab(
state = filterFabState,
rotation = iconRotationDegree, onClick = { state ->
filterFabState = state
})
}
}
This produces the following result:

expandVertically in your enterTransition is not the correct approach for this kind of animation. Per documentation, it animates a clip revealing the content of the animated item from top to bottom, or vice versa. You apply this animation to the entire column (so all items at once), resulting in the gif you have shown us.
Instead, you should use a different enter/exit animation type, maybe a custom animation where you work with the item scaling to emulate the "pop in" effect like such:
scaleFactor.animateTo(2f, tween(easing = FastOutSlowInEasing, durationMillis = 50))
scaleFactor.animateTo(1f, tween(easing = FastOutSlowInEasing, durationMillis = 70))
(the scaleFactor is an animatabale of type Animatable<Float, AnimationVector1D> in this instance).
Then you create such an animatable for each of the column items, i.e. your menu items. After that, just run the animations in a for loop for each menu item inside a coroutine scope (since compose animations are suspend by default, they will run in sequence, use async/awaitAll if you want to do it in parallel).
Also, don't forget to put your animatabales in remember {}, then just use the values you are animating like scaleFactor inside modifiers of your column items, and trigger them inside a LaunchedEffect when you click to expand/close the menu.

How to clip or cut a Composable?

How to clip or cut Composable content to have Image, Button or Composables to have custom shapes? This question is not about using Modifier.clip(), more like accomplishing task with alternative methods that allow outcomes that are not possible or when it's difficult to create a shape like cloud or Squircle.
This is share your knowledge, Q&A-style question which inspired by M3 BottomAppBar or BottomNavigation not having cutout shape, couldn't find question, and drawing a Squircle shape being difficult as in this question.
More and better ways of clipping or customizing shapes and Composables are more than welcome.

One of the ways for achieving cutting or clipping a Composable without the need of creating a custom Composable is using
Modifier.drawWithContent{} with a layer and a BlendMode or PorterDuff modes.
With Jetpack Compose for these modes to work you either need to set alpha less than 1f or use a Layer as in answer here.
I go with layer solution because i don't want to change content alpha
fun ContentDrawScope.drawWithLayer(block: ContentDrawScope.() -> Unit) {
with(drawContext.canvas.nativeCanvas) {
val checkPoint = saveLayer(null, null)
block()
restoreToCount(checkPoint)
}
}
block lambda is the draw scope for Modifier.drawWithContent{} to do clipping
and another extension for simplifying further
fun Modifier.drawWithLayer(block: ContentDrawScope.() -> Unit) = this.then(
Modifier.drawWithContent {
drawWithLayer {
block()
}
}
)
Clip button at the left side
First let's draw the button that is cleared a circle at left side
#Composable
private fun WhoAteMyButton() {
val circleSize = LocalDensity.current.run { 100.dp.toPx() }
Box(
modifier = Modifier
.fillMaxWidth()
.drawWithLayer {
// Destination
drawContent()
// Source
drawCircle(
center = Offset(0f, 10f),
radius = circleSize,
blendMode = BlendMode.SrcOut,
color = Color.Transparent
)
}
) {
Button(
modifier = Modifier
.padding(horizontal = 10.dp)
.fillMaxWidth(),
onClick = { /*TODO*/ }) {
Text("Hello World")
}
}
}
We simply draw a circle but because of BlendMode.SrcOut intersection of destination is removed.
Clip button and Image with custom image
For squircle button i found an image from web
And clipped button and image using this image with
#Composable
private fun ClipComposables() {
Row(
modifier = Modifier.fillMaxWidth(),
horizontalArrangement = Arrangement.SpaceEvenly
) {
val imageBitmap = ImageBitmap.imageResource(id = R.drawable.squircle)
Box(modifier = Modifier
.size(150.dp)
.drawWithLayer {
// Destination
drawContent()
// Source
drawImage(
image = imageBitmap,
dstSize = IntSize(width = size.width.toInt(), height = size.height.toInt()),
blendMode = BlendMode.DstIn
)
}
) {
Box(
modifier = Modifier
.size(150.dp)
.clickable { }
.background(MaterialTheme.colorScheme.inversePrimary),
contentAlignment = Alignment.Center
) {
Text(text = "Squircle", fontSize = 20.sp)
}
}
Box(modifier = Modifier
.size(150.dp)
.drawWithLayer {
// Destination
drawContent()
// Source
drawImage(
image = imageBitmap,
dstSize = IntSize(width = size.width.toInt(), height = size.height.toInt()),
blendMode = BlendMode.DstIn
)
}
) {
Image(
painterResource(id = R.drawable.squirtle),
modifier = Modifier
.size(150.dp),
contentScale = ContentScale.Crop,
contentDescription = ""
)
}
}
}
There are 2 things to note here
1- Blend mode is BlendMode.DstIn because we want texture of Destination with shape of Source
2- Drawing image inside ContentDrawScope with dstSize to match Composable size. By default it's drawn with png size posted above.
Creating a BottomNavigation with cutout shape
#Composable
private fun BottomBarWithCutOutShape() {
val density = LocalDensity.current
val shapeSize = density.run { 70.dp.toPx() }
val cutCornerShape = CutCornerShape(50)
val outline = cutCornerShape.createOutline(
Size(shapeSize, shapeSize),
LocalLayoutDirection.current,
density
)
val icons =
listOf(Icons.Filled.Home, Icons.Filled.Map, Icons.Filled.Settings, Icons.Filled.LocationOn)
Box(
modifier = Modifier.fillMaxWidth()
) {
BottomNavigation(
modifier = Modifier
.drawWithLayer {
with(drawContext.canvas.nativeCanvas) {
val checkPoint = saveLayer(null, null)
val width = size.width
val outlineWidth = outline.bounds.width
val outlineHeight = outline.bounds.height
// Destination
drawContent()
// Source
withTransform(
{
translate(
left = (width - outlineWidth) / 2,
top = -outlineHeight / 2
)
}
) {
drawOutline(
outline = outline,
color = Color.Transparent,
blendMode = BlendMode.Clear
)
}
restoreToCount(checkPoint)
}
},
backgroundColor = Color.White
) {
var selectedIndex by remember { mutableStateOf(0) }
icons.forEachIndexed { index, imageVector: ImageVector ->
if (index == 2) {
Spacer(modifier = Modifier.weight(1f))
BottomNavigationItem(
icon = { Icon(imageVector, contentDescription = null) },
label = null,
selected = selectedIndex == index,
onClick = {
selectedIndex = index
}
)
} else {
BottomNavigationItem(
icon = { Icon(imageVector, contentDescription = null) },
label = null,
selected = selectedIndex == index,
onClick = {
selectedIndex = index
}
)
}
}
}
// This is size fo BottomNavigationItem
val bottomNavigationHeight = LocalDensity.current.run { 56.dp.roundToPx() }
FloatingActionButton(
modifier = Modifier
.align(Alignment.TopCenter)
.offset {
IntOffset(0, -bottomNavigationHeight / 2)
},
shape = cutCornerShape,
onClick = {}
) {
Icon(imageVector = Icons.Default.Add, contentDescription = null)
}
}
}
This code is a bit long but we basically create a shape like we always and create an outline to clip
val cutCornerShape = CutCornerShape(50)
val outline = cutCornerShape.createOutline(
Size(shapeSize, shapeSize),
LocalLayoutDirection.current,
density
)
And before clipping we move this shape section up as half of the height to cut only with half of the outline
withTransform(
{
translate(
left = (width - outlineWidth) / 2,
top = -outlineHeight / 2
)
}
) {
drawOutline(
outline = outline,
color = Color.Transparent,
blendMode = BlendMode.Clear
)
}
Also to have a BottomNavigation such as BottomAppBar that places children on both side
i used a Spacer
icons.forEachIndexed { index, imageVector: ImageVector ->
if (index == 2) {
Spacer(modifier = Modifier.weight(1f))
BottomNavigationItem(
icon = { Icon(imageVector, contentDescription = null) },
label = null,
selected = selectedIndex == index,
onClick = {
selectedIndex = index
}
)
} else {
BottomNavigationItem(
icon = { Icon(imageVector, contentDescription = null) },
label = null,
selected = selectedIndex == index,
onClick = {
selectedIndex = index
}
)
}
}
Then we simply add a FloatingActionButton, i used offset but you can create a bigger parent and put our custom BottomNavigation and button inside it.

How to implement list multiSelect in Jetpack Compose?

I need to implement multiselect for LazyList, which will also change appBar content when list items are long clicked.
For ListView we could do that with just setting choiceMode to CHOICE_MODE_MULTIPLE_MODAL and setting MultiChoiceModeListener.
Is there a way to do this using Compose?

Since you're in control of the whole state in jetpack compose, you can easily create your own multi-select mode. This is an example.
First I created a ViewModel
val dirs: LiveData<DirViewState> = {
DirViewState.Content(dirRepository.targetFolders)}.asFlow().asLiveData()
val all: LiveData<DirViewState> = {
DirViewState.Content(dirRepository.allFolders)
}.asFlow().asLiveData()
val createFolder = mutableStateOf(false)
val refresh = mutableStateOf(false)
val enterSelectMode = mutableStateOf(false)
val selectedAll = mutableStateOf(false)
val selectedList = mutableStateOf(mutableListOf<String>())
fun updateList(path: String){
if(path in selectedList.value){
selectedList.value.remove(path)
}else{
selectedList.value.add(path)
}
}
}
Usage
Card(modifier = Modifier
.width(100.dp)
.height(120.dp)
.padding(8.dp)
.pointerInput(Unit) {
detectTapGestures(
onLongPress = { **viewModel.enterSelectMode.value = true** },
onTap = {
if (viewModel.enterSelectMode.value) {
viewModel.enterSelectMode.value = false
}
}
)
}
,
shape = MaterialTheme.shapes.medium
) {
Image(painter = if (dirModel.dirCover != "") painter
else painterResource(id = R.drawable.thumbnail),
contentDescription = "dirThumbnail",
modifier = Modifier
.fillMaxHeight()
.fillMaxWidth(),
contentScale = ContentScale.FillHeight)
**AnimatedVisibility(
visible = viewModel.enterSelectMode.value,
enter = expandIn(),
exit = shrinkOut()
){
Row(verticalAlignment = Alignment.Top,
horizontalArrangement = Arrangement.Start) {
Checkbox(checked = isSelected.value, onCheckedChange = {
isSelected.value = !isSelected.value
viewModel.updateList(dirModel.dirPath)
})
}
}**
}

Add selected field to some class representing the item. Then just compose proper code based on that field. In compose you don't have to look for some LazyColumn flag or anything like that. You are in control of the whole state of the list.
The same can be said about the AppBar, you can do a simple if there, like if (items.any { it.selected }) // display button

You can simply handle this by the below code:
Fore example This is your list:
LazyColumn {
items(items = filters) { item ->
FilterItem(item)
}
}
and this is your list item View:
#Composable
fun FilterItem(filter: FilterModel) {
val (selected, onSelected) = remember { mutableStateOf(false) }
Card(
shape = RoundedCornerShape(8.dp),
modifier = Modifier
.padding(horizontal = 8.dp)
.border(
width = 1.dp,
colorResource(
if (selected)
R.color.black
else
R.color.white
),
RoundedCornerShape(8.dp)
)) {
Text(
modifier = Modifier
.toggleable(
value =
selected,
onValueChange =
onSelected
)
.padding(8.dp),
text = filter.text)
}
}
and that's it use tooggleable on your click component modifier like here I did on text.

Gradient backround for FAB in Jetpack compose

I want to add a Floating Action Button with a gradient background in Jetpack Compose. I have the following snippet to do so:
FloatingActionButton(
onClick = {
coroutineScope.safeLaunch {
navController.navigate("AddTodoPage") {
launchSingleTop = true
}
}
},
shape = RoundedCornerShape(14.dp),
backgroundColor = Color.Transparent,
modifier = Modifier
.constrainAs(addFab) {
bottom.linkTo(parent.bottom)
end.linkTo(parent.end)
}
.offset(x = (-16).dp, y = (-24).dp)
.background(
brush = Brush.verticalGradient(
colors = BluePinkGradient()
),
shape = RoundedCornerShape(14.dp)
)
) {
Icon(
painter = painterResource(id = R.drawable.ic_add),
contentDescription = "Add icon",
tint = Color.White
)
}
fun BluePinkGradient(inverse: Boolean = false) = when (inverse) {
true -> listOf(
MutedBlue,
MutedPink
)
false -> listOf(
MutedPink,
MutedBlue
)
}
val MutedBlue = Color(0xFF26A69A)
val MutedPink = Color(0xFFEC407A)
But from the image below, the button has a "Whitish" shade on the plus icon. How can I remove that shade or a better way to set the FAB background to a gradient?
Fab Image

'"Whitish" shade on the plus icon' is the result of elevation parameter. You can zero it, but it doesn't looks like you need FAB in the first place.
As you need to custom the button that much, you can use IconButton instead:
IconButton(
onClick = {
},
modifier = Modifier
.background(
brush = Brush.verticalGradient(
colors = BluePinkGradient()
),
shape = RoundedCornerShape(14.dp)
)
) {
Icon(
painter = painterResource(id = R.drawable.ic_undo),
contentDescription = "Add icon",
tint = Color.White
)
}
FloatingActionButton is only applying some Material defaults to the content, it doesn't make it really floating, it has to be done with the container.

I have developed the following solution, which I have confirmed as working:
#OptIn(ExperimentalMaterialApi::class)
#Composable
fun CrazyFloatingActionButton(
onClick: () -> Unit,
modifier: Modifier = Modifier,
interactionSource: MutableInteractionSource = remember { MutableInteractionSource() },
shape: Shape = MaterialTheme.shapes.small.copy(CornerSize(percent = 50)),
gradient: List<Color>,
contentColor: Color = contentColorFor(gradient[0]),
elevation: FloatingActionButtonElevation = FloatingActionButtonDefaults.elevation(),
content: #Composable () -> Unit
) {
Surface(
modifier = modifier,
shape = shape,
contentColor = contentColor,
elevation = elevation.elevation(interactionSource).value,
onClick = onClick,
role = Role.Button,
interactionSource = interactionSource,
indication = rememberRipple()
) {
CompositionLocalProvider(LocalContentAlpha provides contentColor.alpha) {
ProvideTextStyle(MaterialTheme.typography.button) {
Box(
modifier = Modifier
.defaultMinSize(minWidth = 56.dp, minHeight = 56.dp)
.background(brush = Brush.verticalGradient(gradient)),
contentAlignment = Alignment.Center
) { content() }
}
}
}
}
Just prepend Crazy to your Composable and you should be good to go.

Jetpack Compose: IntrinsicMeasurements not supported loading with Accompanist CoilImage in DropdownMenu

I want to build a dropdown menu with items that contain not only text, but also an image. The image should be loaded from an url. I'm using Dropdown Menu and Accompanist to load the image.
But when I try to open the Dropdown Menu, I get java.lang.IllegalStateException: Intrinsic measurements are not currently supported by SubcomposeLayout.
I've tried to play around with Intrinsics in my Composables like here https://developer.android.com/codelabs/jetpack-compose-layouts#10, but it didn't work. If I don't use CoilImage, but get a painter from resources with Image, everything works fine.
Is there a way to solve it?
#Composable
fun DropdownChildren(
items: List<ChildUiModel>,
chosenChild: ChildUiModel?,
onChildChosen: (ChildUiModel) -> Unit
) {
var expanded by remember { mutableStateOf(false) }
var selectedIndex by remember { mutableStateOf(0) }
Box(modifier = Modifier
.fillMaxSize()
.wrapContentSize(Alignment.TopStart)) {
Row(modifier = Modifier
.fillMaxSize()
.clickable(onClick = { expanded = true })) {
ChildrenDropdownMenuItem(
imageUrl = "https://oneyearwithjesus.files.wordpress.com/2014/09/shutterstock_20317516.jpg",
text = items[selectedIndex].name?: "No name",
chosen = false)
}
DropdownMenu(
expanded = expanded,
onDismissRequest = { expanded = false },
modifier = Modifier
.fillMaxWidth()
.requiredSizeIn(maxHeight = 500.dp)
) {
items.forEachIndexed { index, child ->
DropdownMenuItem(
modifier = Modifier
.background(color = if (child.id == chosenChild?.id) appColors.secondary else appColors.primary),
onClick = {
expanded = false
selectedIndex = index
onChildChosen(items[selectedIndex])
}) {
ChildrenDropdownMenuItem(
imageUrl = "https://oneyearwithjesus.files.wordpress.com/2014/09/shutterstock_20317516.jpg",
text = child.name,
chosen = child.id == chosenChild?.id)
}
}
}
}
}
#Composable
fun ChildrenDropdownMenuItem(
imageUrl: String,
text: String,
chosen: Boolean
){
Row(){
Avatar(url = imageUrl)
Text(text = text,
style = AppTheme.typography.h4,
color = if (chosen) appColors.primary else appColors.secondary,
modifier = Modifier
.fillMaxWidth()
.align(Alignment.CenterVertically))
}
}
#Composable
fun Avatar(
url: String
){
val contentPadding = PaddingValues(8.dp, 8.dp, 12.dp, 8.dp)
CoilImage(
data = url,
) { imageState ->
when (imageState) {
is ImageLoadState.Success -> {
MaterialLoadingImage(
result = imageState,
contentDescription = "avatar",
modifier = Modifier
.padding(contentPadding)
.clip(CircleShape)
.size(48.dp),
contentScale = ContentScale.Crop,
fadeInEnabled = true,
fadeInDurationMs = 600,
)
}
is ImageLoadState.Error -> CoilImage(
data = "https://www.padtinc.com/blog/wp-content/uploads/2020/09/plc-errors.jpg",
contentDescription = "error",
contentScale = ContentScale.Crop,
modifier = Modifier
.padding(contentPadding)
.clip(CircleShape)
.size(48.dp)
)
ImageLoadState.Loading -> CircularProgressIndicator()
ImageLoadState.Empty -> {}
}
}
}

CoilImage is now Deprecated,
use this
Image(
painter = rememberCoilPainter("https://picsum.photos/300/300"),
contentDescription = stringResource(R.string.image_content_desc),
previewPlaceholder = R.drawable.placeholder,
)

As you mentioned on the bug, this has already been fixed in v0.8.0 of Accompanist. You need to use the new rememberCoilPainter() though, and not the deprecated CoilImage().