LazyItemScope

Receiver scope being used by the item content parameter of LazyColumn/Row.

Summary

Public functions
open Modifier
Modifier.animateItem(
    fadeInSpec: FiniteAnimationSpec<Float>?,
    placementSpec: FiniteAnimationSpec<IntOffset>?,
    fadeOutSpec: FiniteAnimationSpec<Float>?
)

This modifier animates the item appearance (fade in), disappearance (fade out) and placement changes (such as an item reordering).
Cmn
Modifier
Modifier.fillParentMaxHeight(
    fraction: @FloatRange(from = 0.0, to = 1.0) Float
)

Have the content fill the Constraints.maxHeight of the incoming measurement constraints by setting the minimum height to be equal to the maximum height multiplied by fraction.
Cmn
Modifier
Modifier.fillParentMaxSize(
    fraction: @FloatRange(from = 0.0, to = 1.0) Float
)

Have the content fill the Constraints.maxWidth and Constraints.maxHeight of the parent measurement constraints by setting the minimum width to be equal to the maximum width multiplied by fraction and the minimum height to be equal to the maximum height multiplied by fraction.
Cmn
Modifier
Modifier.fillParentMaxWidth(
    fraction: @FloatRange(from = 0.0, to = 1.0) Float
)

Have the content fill the Constraints.maxWidth of the parent measurement constraints by setting the minimum width to be equal to the maximum width multiplied by fraction.
Cmn

Public functions

animateItem

Cmn 
open fun Modifier.animateItem(
    fadeInSpec: FiniteAnimationSpec<Float>? = spring(stiffness = Spring.StiffnessMediumLow),
    placementSpec: FiniteAnimationSpec<IntOffset>? = spring(
                stiffness = Spring.StiffnessMediumLow,
                visibilityThreshold = IntOffset.VisibilityThreshold
            ),
    fadeOutSpec: FiniteAnimationSpec<Float>? = spring(stiffness = Spring.StiffnessMediumLow)
): Modifier

This modifier animates the item appearance (fade in), disappearance (fade out) and placement changes (such as an item reordering).

You should also provide a key via LazyListScope.item/LazyListScope.items for this modifier to enable animations.

import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.lazy.LazyColumn
import androidx.compose.foundation.lazy.items
import androidx.compose.material.Button
import androidx.compose.material.Text
import androidx.compose.runtime.State
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.ui.Modifier

var list by remember { mutableStateOf(listOf("1", "2", "3")) }
Column {
    Button(onClick = { list = list + "${list.count() + 1}" }) { Text("Add new item") }
    Button(onClick = { list = list.shuffled() }) { Text("Shuffle") }
    LazyColumn { items(list, key = { it }) { Text("Item $it", Modifier.animateItem()) } }
}
Parameters
fadeInSpec: FiniteAnimationSpec<Float>? = spring(stiffness = Spring.StiffnessMediumLow)

an animation specs to use for animating the item appearance. When null is provided the item will be appearing without animations.
placementSpec: FiniteAnimationSpec<IntOffset>? = spring( stiffness = Spring.StiffnessMediumLow, visibilityThreshold = IntOffset.VisibilityThreshold )

an animation specs that will be used to animate the item placement. Aside from item reordering all other position changes caused by events like arrangement or alignment changes will also be animated. When null is provided no animations will happen.
fadeOutSpec: FiniteAnimationSpec<Float>? = spring(stiffness = Spring.StiffnessMediumLow)

an animation specs to use for animating the item disappearance. When null is provided the item will be disappearance without animations.

fillParentMaxHeight

Cmn 
fun Modifier.fillParentMaxHeight(
    fraction: @FloatRange(from = 0.0, to = 1.0) Float = 1.0f
): Modifier

Have the content fill the Constraints.maxHeight of the incoming measurement constraints by setting the minimum height to be equal to the maximum height multiplied by fraction. Note that, by default, the fraction is 1, so the modifier will make the content fill the whole parent height. fraction must be between 0 and 1.

Regular Modifier.fillMaxHeight can't work inside the scrolling vertically layouts as the items are measured with Constraints.Infinity as the constraints for the main axis.

fillParentMaxSize

Cmn 
fun Modifier.fillParentMaxSize(
    fraction: @FloatRange(from = 0.0, to = 1.0) Float = 1.0f
): Modifier

Have the content fill the Constraints.maxWidth and Constraints.maxHeight of the parent measurement constraints by setting the minimum width to be equal to the maximum width multiplied by fraction and the minimum height to be equal to the maximum height multiplied by fraction. Note that, by default, the fraction is 1, so the modifier will make the content fill the whole available space. fraction must be between 0 and 1.

Regular Modifier.fillMaxSize can't work inside the scrolling layouts as the items are measured with Constraints.Infinity as the constraints for the main axis.

fillParentMaxWidth

Cmn 
fun Modifier.fillParentMaxWidth(
    fraction: @FloatRange(from = 0.0, to = 1.0) Float = 1.0f
): Modifier

Have the content fill the Constraints.maxWidth of the parent measurement constraints by setting the minimum width to be equal to the maximum width multiplied by fraction. Note that, by default, the fraction is 1, so the modifier will make the content fill the whole parent width. fraction must be between 0 and 1.

Regular Modifier.fillMaxWidth can't work inside the scrolling horizontally layouts as the items are measured with Constraints.Infinity as the constraints for the main axis.