androidx.compose.foundation.lazy.grid

Common/All

Interfaces

GridCells	This class describes the count and the sizes of columns in vertical grids, or rows in horizontal grids.	Cmn
LazyGridItemInfo	Contains useful information about an individual item in lazy grids like LazyVerticalGrid.	Cmn
LazyGridItemScope	Receiver scope being used by the item content parameter of LazyVerticalGrid.	Cmn
LazyGridItemSpanScope	Scope of lambdas used to calculate the spans of items in lazy grids.	Cmn
LazyGridLayoutInfo	Contains useful information about the currently displayed layout state of lazy grids like LazyVerticalGrid.	Cmn
LazyGridPrefetchScope	Scope for callbacks in LazyGridPrefetchStrategy which allows prefetches to be requested.	Cmn
LazyGridPrefetchStrategy	Implementations of this interface control which indices of a LazyGrid should be prefetched (precomposed and premeasured during idle time) as the user interacts with it.	Cmn
LazyGridScope	Receiver scope which is used by LazyVerticalGrid.	Cmn

Classes

GridCells.Adaptive	Defines a grid with as many rows or columns as possible on the condition that every cell has at least minSize space and all extra space distributed evenly.	Cmn
GridCells.Fixed	Defines a grid with fixed number of rows or columns.	Cmn
GridCells.FixedSize	Defines a grid with as many rows or columns as possible on the condition that every cell takes exactly size space.	Cmn
GridItemSpan	Represents the span of an item in a LazyVerticalGrid or a LazyHorizontalGrid.	Cmn
LazyGridState	A state object that can be hoisted to control and observe scrolling.	Cmn

Annotations

LazyGridScopeMarker

DSL marker used to distinguish between lazy grid dsl scope and the item content scope.

Cmn

Top-level functions summary

GridItemSpan	GridItemSpan(currentLineSpan: @IntRange(from = 1) Int) Creates a GridItemSpan with a specified currentLineSpan.	Cmn
LazyGridPrefetchStrategy	@ExperimentalFoundationApi LazyGridPrefetchStrategy(nestedPrefetchItemCount: Int) Creates an instance of the default LazyGridPrefetchStrategy, allowing for customization of the nested prefetch count.	Cmn
Unit	@Composable LazyHorizontalGrid(     rows: GridCells,     modifier: Modifier,     state: LazyGridState,     contentPadding: PaddingValues,     reverseLayout: Boolean,     horizontalArrangement: Arrangement.Horizontal,     verticalArrangement: Arrangement.Vertical,     flingBehavior: FlingBehavior,     userScrollEnabled: Boolean,     content: LazyGridScope.() -> Unit ) A lazy horizontal grid layout.	Cmn
LazyLayoutScrollScope	LazyLayoutScrollScope(state: LazyGridState, scrollScope: ScrollScope) An implementation of LazyLayoutScrollScope that can be used with LazyGrids.	Cmn
Unit	@Composable LazyVerticalGrid(     columns: GridCells,     modifier: Modifier,     state: LazyGridState,     contentPadding: PaddingValues,     reverseLayout: Boolean,     verticalArrangement: Arrangement.Vertical,     horizontalArrangement: Arrangement.Horizontal,     flingBehavior: FlingBehavior,     userScrollEnabled: Boolean,     content: LazyGridScope.() -> Unit ) A lazy vertical grid layout.	Cmn
LazyGridState	@Composable rememberLazyGridState(     initialFirstVisibleItemIndex: Int,     initialFirstVisibleItemScrollOffset: Int ) Creates a LazyGridState that is remembered across compositions.	Cmn
LazyGridState	@ExperimentalFoundationApi @Composable rememberLazyGridState(     initialFirstVisibleItemIndex: Int,     initialFirstVisibleItemScrollOffset: Int,     prefetchStrategy: LazyGridPrefetchStrategy ) Creates a LazyGridState that is remembered across compositions.	Cmn

Extension functions summary

inline Unit	<T : Any?> LazyGridScope.items(     items: Array<T>,     noinline key: ((item) -> Any)?,     noinline span: (LazyGridItemSpanScope.(item) -> GridItemSpan)?,     noinline contentType: (item) -> Any,     crossinline itemContent: @Composable LazyGridItemScope.(item) -> Unit ) Adds an array of items.	Cmn
inline Unit	<T : Any?> LazyGridScope.items(     items: List<T>,     noinline key: ((item) -> Any)?,     noinline span: (LazyGridItemSpanScope.(item) -> GridItemSpan)?,     noinline contentType: (item) -> Any,     crossinline itemContent: @Composable LazyGridItemScope.(item) -> Unit ) Adds a list of items.	Cmn
inline Unit	<T : Any?> LazyGridScope.itemsIndexed(     items: Array<T>,     noinline key: ((index: Int, item) -> Any)?,     noinline span: (LazyGridItemSpanScope.(index: Int, item) -> GridItemSpan)?,     crossinline contentType: (index: Int, item) -> Any,     crossinline itemContent: @Composable LazyGridItemScope.(index: Int, item) -> Unit ) Adds an array of items where the content of an item is aware of its index.	Cmn
inline Unit	<T : Any?> LazyGridScope.itemsIndexed(     items: List<T>,     noinline key: ((index: Int, item) -> Any)?,     noinline span: (LazyGridItemSpanScope.(index: Int, item) -> GridItemSpan)?,     crossinline contentType: (index: Int, item) -> Any,     crossinline itemContent: @Composable LazyGridItemScope.(index: Int, item) -> Unit ) Adds a list of items where the content of an item is aware of its index.	Cmn

Top-level functions

GridItemSpan

Cmn

Artifact: androidx.compose.foundation:foundation

View Source

Added in 1.2.0

fun GridItemSpan(currentLineSpan: @IntRange(from = 1) Int): GridItemSpan

Creates a GridItemSpan with a specified currentLineSpan. This will be the horizontal span for an item of a LazyVerticalGrid and the vertical span for a LazyHorizontalGrid.

LazyGridPrefetchStrategy

Cmn

Artifact: androidx.compose.foundation:foundation

View Source

Added in 1.7.0

@ExperimentalFoundationApi
fun LazyGridPrefetchStrategy(nestedPrefetchItemCount: Int = 2): LazyGridPrefetchStrategy

Creates an instance of the default LazyGridPrefetchStrategy, allowing for customization of the nested prefetch count.

Parameters
nestedPrefetchItemCount: Int = 2	specifies how many inner items should be prefetched when this LazyGrid is nested inside another LazyLayout. For example, if this is the state for a horizontal LazyGrid nested in a vertical LazyGrid, you might want to set this to the number of items that will be visible when this grid is scrolled into view.

LazyHorizontalGrid

Cmn

Artifact: androidx.compose.foundation:foundation

View Source

Added in 1.2.0

@Composable
fun LazyHorizontalGrid(
    rows: GridCells,
    modifier: Modifier = Modifier,
    state: LazyGridState = rememberLazyGridState(),
    contentPadding: PaddingValues = PaddingValues(0.dp),
    reverseLayout: Boolean = false,
    horizontalArrangement: Arrangement.Horizontal = if (!reverseLayout) Arrangement.Start else Arrangement.End,
    verticalArrangement: Arrangement.Vertical = Arrangement.Top,
    flingBehavior: FlingBehavior = ScrollableDefaults.flingBehavior(),
    userScrollEnabled: Boolean = true,
    content: LazyGridScope.() -> Unit
): Unit

A lazy horizontal grid layout. It composes only visible columns of the grid.

Sample:

import androidx.compose.foundation.border
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.width
import androidx.compose.foundation.layout.wrapContentSize
import androidx.compose.foundation.lazy.grid.GridCells
import androidx.compose.foundation.lazy.grid.LazyHorizontalGrid
import androidx.compose.foundation.lazy.grid.items
import androidx.compose.foundation.lazy.grid.itemsIndexed
import androidx.compose.material.Text
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp

val itemsList = (0..5).toList()
val itemsIndexedList = listOf("A", "B", "C")

val itemModifier = Modifier.border(1.dp, Color.Blue).width(80.dp).wrapContentSize()

LazyHorizontalGrid(
    rows = GridCells.Fixed(3),
    horizontalArrangement = Arrangement.spacedBy(16.dp),
    verticalArrangement = Arrangement.spacedBy(16.dp)
) {
    items(itemsList) { Text("Item is $it", itemModifier) }

    item { Text("Single item", itemModifier) }

    itemsIndexed(itemsIndexedList) { index, item ->
        Text("Item at index $index is $item", itemModifier)
    }
}

Sample with custom item spans:

import androidx.compose.foundation.border
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.width
import androidx.compose.foundation.layout.wrapContentSize
import androidx.compose.foundation.lazy.grid.GridCells
import androidx.compose.foundation.lazy.grid.GridItemSpan
import androidx.compose.foundation.lazy.grid.LazyHorizontalGrid
import androidx.compose.foundation.lazy.grid.items
import androidx.compose.material.Text
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp

val sections = (0 until 25).toList().chunked(5)
LazyHorizontalGrid(
    rows = GridCells.Fixed(3),
    horizontalArrangement = Arrangement.spacedBy(16.dp),
    verticalArrangement = Arrangement.spacedBy(16.dp)
) {
    sections.forEachIndexed { index, items ->
        item(span = { GridItemSpan(maxLineSpan) }) {
            Text(
                "This is section $index",
                Modifier.border(1.dp, Color.Gray).width(80.dp).wrapContentSize()
            )
        }
        items(
            items,
            // not required as it is the default
            span = { GridItemSpan(1) }
        ) {
            Text("Item $it", Modifier.border(1.dp, Color.Blue).width(80.dp).wrapContentSize())
        }
    }
}

Parameters
rows: GridCells	a class describing how cells form rows, see GridCells doc for more information
modifier: Modifier = Modifier	the modifier to apply to this layout
state: LazyGridState = rememberLazyGridState()	the state object to be used to control or observe the list's state
contentPadding: PaddingValues = PaddingValues(0.dp)	specify a padding around the whole content
reverseLayout: Boolean = false	reverse the direction of scrolling and layout. When true, items are laid out in the reverse order and LazyGridState.firstVisibleItemIndex == 0 means that grid is scrolled to the end. Note that reverseLayout does not change the behavior of horizontalArrangement, e.g. with 123### becomes 321###.
horizontalArrangement: Arrangement.Horizontal = if (!reverseLayout) Arrangement.Start else Arrangement.End	The horizontal arrangement of the layout's children
verticalArrangement: Arrangement.Vertical = Arrangement.Top	The vertical arrangement of the layout's children
flingBehavior: FlingBehavior = ScrollableDefaults.flingBehavior()	logic describing fling behavior
userScrollEnabled: Boolean = true	whether the scrolling via the user gestures or accessibility actions is allowed. You can still scroll programmatically using the state even when it is disabled.
content: LazyGridScope.() -> Unit	the LazyGridScope which describes the content

LazyLayoutScrollScope

Cmn

Artifact: androidx.compose.foundation:foundation

View Source

Added in 1.8.0-alpha04

fun LazyLayoutScrollScope(state: LazyGridState, scrollScope: ScrollScope): LazyLayoutScrollScope

An implementation of LazyLayoutScrollScope that can be used with LazyGrids.

import androidx.compose.animation.core.tween
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.height
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.layout.size
import androidx.compose.foundation.lazy.grid.GridCells
import androidx.compose.foundation.lazy.grid.LazyGridState
import androidx.compose.foundation.lazy.grid.LazyHorizontalGrid
import androidx.compose.foundation.lazy.grid.LazyLayoutScrollScope
import androidx.compose.foundation.lazy.grid.items
import androidx.compose.foundation.lazy.grid.rememberLazyGridState
import androidx.compose.foundation.lazy.layout.LazyLayoutScrollScope
import androidx.compose.foundation.rememberScrollState
import androidx.compose.foundation.verticalScroll
import androidx.compose.material.Button
import androidx.compose.material.Text
import androidx.compose.runtime.remember
import androidx.compose.runtime.rememberCoroutineScope
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp

suspend fun LazyGridState.customScroll(block: suspend LazyLayoutScrollScope.() -> Unit) =
    scroll {
        block.invoke(LazyLayoutScrollScope(this@customScroll, this))
    }

val itemsList = (0..100).toList()
val state = rememberLazyGridState()
val scope = rememberCoroutineScope()

Column(Modifier.verticalScroll(rememberScrollState())) {
    Button(
        onClick = {
            scope.launch {
                state.customScroll {
                    snapToItem(40, 0) // teleport to item 40
                    val distance = calculateDistanceTo(50).toFloat()
                    var previousValue = 0f
                    androidx.compose.animation.core.animate(
                        0f,
                        distance,
                        animationSpec = tween(5_000)
                    ) { currentValue, _ ->
                        previousValue += scrollBy(currentValue - previousValue)
                    }
                }
            }
        }
    ) {
        Text("Scroll To Item 50")
    }
    LazyHorizontalGrid(
        state = state,
        rows = GridCells.Fixed(3),
        modifier = Modifier.height(600.dp).fillMaxWidth()
    ) {
        items(itemsList) {
            Box(Modifier.padding(2.dp).background(Color.Red).size(45.dp)) {
                Text(it.toString())
            }
        }
    }
}

Parameters
state: LazyGridState	The LazyGridState associated with the layout where this custom scroll should be performed.
scrollScope: ScrollScope	The base ScrollScope where the scroll session was created.

Returns
LazyLayoutScrollScope	An implementation of LazyLayoutScrollScope that works with LazyHorizontalGrid and LazyVerticalGrid.

LazyVerticalGrid

Cmn

Artifact: androidx.compose.foundation:foundation

View Source

Added in 1.2.0

@Composable
fun LazyVerticalGrid(
    columns: GridCells,
    modifier: Modifier = Modifier,
    state: LazyGridState = rememberLazyGridState(),
    contentPadding: PaddingValues = PaddingValues(0.dp),
    reverseLayout: Boolean = false,
    verticalArrangement: Arrangement.Vertical = if (!reverseLayout) Arrangement.Top else Arrangement.Bottom,
    horizontalArrangement: Arrangement.Horizontal = Arrangement.Start,
    flingBehavior: FlingBehavior = ScrollableDefaults.flingBehavior(),
    userScrollEnabled: Boolean = true,
    content: LazyGridScope.() -> Unit
): Unit

A lazy vertical grid layout. It composes only visible rows of the grid.

Sample:

import androidx.compose.foundation.border
import androidx.compose.foundation.layout.height
import androidx.compose.foundation.layout.wrapContentSize
import androidx.compose.foundation.lazy.grid.GridCells
import androidx.compose.foundation.lazy.grid.LazyVerticalGrid
import androidx.compose.foundation.lazy.grid.items
import androidx.compose.foundation.lazy.grid.itemsIndexed
import androidx.compose.material.Text
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp

val itemsList = (0..5).toList()
val itemsIndexedList = listOf("A", "B", "C")

val itemModifier = Modifier.border(1.dp, Color.Blue).height(80.dp).wrapContentSize()

LazyVerticalGrid(columns = GridCells.Fixed(3)) {
    items(itemsList) { Text("Item is $it", itemModifier) }
    item { Text("Single item", itemModifier) }
    itemsIndexed(itemsIndexedList) { index, item ->
        Text("Item at index $index is $item", itemModifier)
    }
}

Sample with custom item spans:

import androidx.compose.foundation.border
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.height
import androidx.compose.foundation.layout.wrapContentSize
import androidx.compose.foundation.lazy.grid.GridCells
import androidx.compose.foundation.lazy.grid.GridItemSpan
import androidx.compose.foundation.lazy.grid.LazyVerticalGrid
import androidx.compose.foundation.lazy.grid.items
import androidx.compose.material.Text
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp

val sections = (0 until 25).toList().chunked(5)
LazyVerticalGrid(
    columns = GridCells.Fixed(3),
    horizontalArrangement = Arrangement.spacedBy(16.dp),
    verticalArrangement = Arrangement.spacedBy(16.dp)
) {
    sections.forEachIndexed { index, items ->
        item(span = { GridItemSpan(maxLineSpan) }) {
            Text(
                "This is section $index",
                Modifier.border(1.dp, Color.Gray).height(80.dp).wrapContentSize()
            )
        }
        items(
            items,
            // not required as it is the default
            span = { GridItemSpan(1) }
        ) {
            Text("Item $it", Modifier.border(1.dp, Color.Blue).height(80.dp).wrapContentSize())
        }
    }
}

Parameters
columns: GridCells	describes the count and the size of the grid's columns, see GridCells doc for more information
modifier: Modifier = Modifier	the modifier to apply to this layout
state: LazyGridState = rememberLazyGridState()	the state object to be used to control or observe the list's state
contentPadding: PaddingValues = PaddingValues(0.dp)	specify a padding around the whole content
reverseLayout: Boolean = false	reverse the direction of scrolling and layout. When true, items will be laid out in the reverse order and LazyGridState.firstVisibleItemIndex == 0 means that grid is scrolled to the bottom. Note that reverseLayout does not change the behavior of verticalArrangement, e.g. with Arrangement.Top (top) 123### (bottom) becomes (top) 321### (bottom).
verticalArrangement: Arrangement.Vertical = if (!reverseLayout) Arrangement.Top else Arrangement.Bottom	The vertical arrangement of the layout's children
horizontalArrangement: Arrangement.Horizontal = Arrangement.Start	The horizontal arrangement of the layout's children
flingBehavior: FlingBehavior = ScrollableDefaults.flingBehavior()	logic describing fling behavior
userScrollEnabled: Boolean = true	whether the scrolling via the user gestures or accessibility actions is allowed. You can still scroll programmatically using the state even when it is disabled.
content: LazyGridScope.() -> Unit	the LazyGridScope which describes the content

rememberLazyGridState

Cmn

Artifact: androidx.compose.foundation:foundation

View Source

Added in 1.2.0

@Composable
fun rememberLazyGridState(
    initialFirstVisibleItemIndex: Int = 0,
    initialFirstVisibleItemScrollOffset: Int = 0
): LazyGridState

Creates a LazyGridState that is remembered across compositions.

Changes to the provided initial values will not result in the state being recreated or changed in any way if it has already been created.

Parameters
initialFirstVisibleItemIndex: Int = 0	the initial value for LazyGridState.firstVisibleItemIndex
initialFirstVisibleItemScrollOffset: Int = 0	the initial value for LazyGridState.firstVisibleItemScrollOffset

rememberLazyGridState

Cmn

Artifact: androidx.compose.foundation:foundation

View Source

Added in 1.7.0

@ExperimentalFoundationApi
@Composable
fun rememberLazyGridState(
    initialFirstVisibleItemIndex: Int = 0,
    initialFirstVisibleItemScrollOffset: Int = 0,
    prefetchStrategy: LazyGridPrefetchStrategy = remember { LazyGridPrefetchStrategy() }
): LazyGridState

Creates a LazyGridState that is remembered across compositions.

Changes to the provided initial values will not result in the state being recreated or changed in any way if it has already been created.

Parameters
initialFirstVisibleItemIndex: Int = 0	the initial value for LazyGridState.firstVisibleItemIndex
initialFirstVisibleItemScrollOffset: Int = 0	the initial value for LazyGridState.firstVisibleItemScrollOffset
prefetchStrategy: LazyGridPrefetchStrategy = remember { LazyGridPrefetchStrategy() }	the LazyGridPrefetchStrategy to use for prefetching content in this grid

Extension functions

items

Cmn

Artifact: androidx.compose.foundation:foundation

View Source

Added in 1.2.0

inline fun <T : Any?> LazyGridScope.items(
    items: Array<T>,
    noinline key: ((item) -> Any)? = null,
    noinline span: (LazyGridItemSpanScope.(item) -> GridItemSpan)? = null,
    noinline contentType: (item) -> Any = { null },
    crossinline itemContent: @Composable LazyGridItemScope.(item) -> Unit
): Unit

Adds an array of items.

Parameters
items: Array<T>	the data array
noinline key: ((item) -> Any)? = null	a factory of stable and unique keys representing the item. Using the same key for multiple items in the grid is not allowed. Type of the key should be saveable via Bundle on Android. If null is passed the position in the grid will represent the key. When you specify the key the scroll position will be maintained based on the key, which means if you add/remove items before the current visible item the item with the given key will be kept as the first visible one.This can be overridden by calling LazyGridState.requestScrollToItem.
noinline span: (LazyGridItemSpanScope.(item) -> GridItemSpan)? = null	define custom spans for the items. Default is 1x1. It is good practice to leave it null when this matches the intended behavior, as providing a custom implementation impacts performance
noinline contentType: (item) -> Any = { null }	a factory of the content types for the item. The item compositions of the same type could be reused more efficiently. Note that null is a valid type and items of such type will be considered compatible.
crossinline itemContent: @Composable LazyGridItemScope.(item) -> Unit	the content displayed by a single item

items

Cmn

Artifact: androidx.compose.foundation:foundation

View Source

inline fun <T : Any?> LazyGridScope.items(
    items: List<T>,
    noinline key: ((item) -> Any)? = null,
    noinline span: (LazyGridItemSpanScope.(item) -> GridItemSpan)? = null,
    noinline contentType: (item) -> Any = { null },
    crossinline itemContent: @Composable LazyGridItemScope.(item) -> Unit
): Unit

Adds a list of items.

Parameters
items: List<T>	the data list
noinline key: ((item) -> Any)? = null	a factory of stable and unique keys representing the item. Using the same key for multiple items in the grid is not allowed. Type of the key should be saveable via Bundle on Android. If null is passed the position in the grid will represent the key. When you specify the key the scroll position will be maintained based on the key, which means if you add/remove items before the current visible item the item with the given key will be kept as the first visible one. This can be overridden by calling LazyGridState.requestScrollToItem.
noinline span: (LazyGridItemSpanScope.(item) -> GridItemSpan)? = null	define custom spans for the items. Default is 1x1. It is good practice to leave it null when this matches the intended behavior, as providing a custom implementation impacts performance
noinline contentType: (item) -> Any = { null }	a factory of the content types for the item. The item compositions of the same type could be reused more efficiently. Note that null is a valid type and items of such type will be considered compatible.
crossinline itemContent: @Composable LazyGridItemScope.(item) -> Unit	the content displayed by a single item

itemsIndexed

Cmn

Artifact: androidx.compose.foundation:foundation

View Source

Added in 1.2.0

inline fun <T : Any?> LazyGridScope.itemsIndexed(
    items: Array<T>,
    noinline key: ((index: Int, item) -> Any)? = null,
    noinline span: (LazyGridItemSpanScope.(index: Int, item) -> GridItemSpan)? = null,
    crossinline contentType: (index: Int, item) -> Any = { _, _ -> null },
    crossinline itemContent: @Composable LazyGridItemScope.(index: Int, item) -> Unit
): Unit

Adds an array of items where the content of an item is aware of its index.

Parameters
items: Array<T>	the data array
noinline key: ((index: Int, item) -> Any)? = null	a factory of stable and unique keys representing the item. Using the same key for multiple items in the grid is not allowed. Type of the key should be saveable via Bundle on Android. If null is passed the position in the grid will represent the key. When you specify the key the scroll position will be maintained based on the key, which means if you add/remove items before the current visible item the item with the given key will be kept as the first visible one. This can be overridden by calling LazyGridState.requestScrollToItem.
noinline span: (LazyGridItemSpanScope.(index: Int, item) -> GridItemSpan)? = null	define custom spans for the items. Default is 1x1. It is good practice to leave it null when this matches the intended behavior, as providing a custom implementation impacts performance
crossinline contentType: (index: Int, item) -> Any = { _, _ -> null }	a factory of the content types for the item. The item compositions of the same type could be reused more efficiently. Note that null is a valid type and items of such type will be considered compatible.
crossinline itemContent: @Composable LazyGridItemScope.(index: Int, item) -> Unit	the content displayed by a single item

itemsIndexed

Cmn

Artifact: androidx.compose.foundation:foundation

View Source

inline fun <T : Any?> LazyGridScope.itemsIndexed(
    items: List<T>,
    noinline key: ((index: Int, item) -> Any)? = null,
    noinline span: (LazyGridItemSpanScope.(index: Int, item) -> GridItemSpan)? = null,
    crossinline contentType: (index: Int, item) -> Any = { _, _ -> null },
    crossinline itemContent: @Composable LazyGridItemScope.(index: Int, item) -> Unit
): Unit

Adds a list of items where the content of an item is aware of its index.

Parameters
items: List<T>	the data list
noinline key: ((index: Int, item) -> Any)? = null	a factory of stable and unique keys representing the item. Using the same key for multiple items in the grid is not allowed. Type of the key should be saveable via Bundle on Android. If null is passed the position in the grid will represent the key. When you specify the key the scroll position will be maintained based on the key, which means if you add/remove items before the current visible item the item with the given key will be kept as the first visible one. This can be overridden by calling LazyGridState.requestScrollToItem.
noinline span: (LazyGridItemSpanScope.(index: Int, item) -> GridItemSpan)? = null	define custom spans for the items. Default is 1x1. It is good practice to leave it null when this matches the intended behavior, as providing a custom implementation impacts performance
crossinline contentType: (index: Int, item) -> Any = { _, _ -> null }	a factory of the content types for the item. The item compositions of the same type could be reused more efficiently. Note that null is a valid type and items of such type will be considered compatible.
crossinline itemContent: @Composable LazyGridItemScope.(index: Int, item) -> Unit	the content displayed by a single item