Add overload of LazyLayout which accepts a lambda of LazyLayoutItemProvider
This overload allows users to write a more efficient code as the item provider can be updated without extra recomposition.
Relnote: Overload of LazyLayout added, it accepts a lambda of LazyLayoutItemProvider, not a plain object as it was before. The previous overload is deprecated.
Test: run lazy/layout tests
Change-Id: I42a5a3d5933deaccac5b5fc6df15c47194cf8b05
diff --git a/compose/foundation/foundation/api/current.txt b/compose/foundation/foundation/api/current.txt
index 5383dcd7..8f3ee10 100644
--- a/compose/foundation/foundation/api/current.txt
+++ b/compose/foundation/foundation/api/current.txt
@@ -881,7 +881,8 @@
}
public final class LazyLayoutKt {
- method @SuppressCompatibility @androidx.compose.foundation.ExperimentalFoundationApi @androidx.compose.runtime.Composable public static void LazyLayout(androidx.compose.foundation.lazy.layout.LazyLayoutItemProvider itemProvider, optional androidx.compose.ui.Modifier modifier, optional androidx.compose.foundation.lazy.layout.LazyLayoutPrefetchState? prefetchState, kotlin.jvm.functions.Function2<? super androidx.compose.foundation.lazy.layout.LazyLayoutMeasureScope,? super androidx.compose.ui.unit.Constraints,? extends androidx.compose.ui.layout.MeasureResult> measurePolicy);
+ method @Deprecated @SuppressCompatibility @androidx.compose.foundation.ExperimentalFoundationApi @androidx.compose.runtime.Composable public static void LazyLayout(androidx.compose.foundation.lazy.layout.LazyLayoutItemProvider itemProvider, optional androidx.compose.ui.Modifier modifier, optional androidx.compose.foundation.lazy.layout.LazyLayoutPrefetchState? prefetchState, kotlin.jvm.functions.Function2<? super androidx.compose.foundation.lazy.layout.LazyLayoutMeasureScope,? super androidx.compose.ui.unit.Constraints,? extends androidx.compose.ui.layout.MeasureResult> measurePolicy);
+ method @SuppressCompatibility @androidx.compose.foundation.ExperimentalFoundationApi @androidx.compose.runtime.Composable public static void LazyLayout(kotlin.jvm.functions.Function0<? extends androidx.compose.foundation.lazy.layout.LazyLayoutItemProvider> itemProvider, optional androidx.compose.ui.Modifier modifier, optional androidx.compose.foundation.lazy.layout.LazyLayoutPrefetchState? prefetchState, kotlin.jvm.functions.Function2<? super androidx.compose.foundation.lazy.layout.LazyLayoutMeasureScope,? super androidx.compose.ui.unit.Constraints,? extends androidx.compose.ui.layout.MeasureResult> measurePolicy);
}
@SuppressCompatibility @androidx.compose.foundation.ExperimentalFoundationApi @androidx.compose.runtime.Stable public sealed interface LazyLayoutMeasureScope extends androidx.compose.ui.layout.MeasureScope {
diff --git a/compose/foundation/foundation/api/restricted_current.txt b/compose/foundation/foundation/api/restricted_current.txt
index 2bdd519..4667dba 100644
--- a/compose/foundation/foundation/api/restricted_current.txt
+++ b/compose/foundation/foundation/api/restricted_current.txt
@@ -883,7 +883,8 @@
}
public final class LazyLayoutKt {
- method @SuppressCompatibility @androidx.compose.foundation.ExperimentalFoundationApi @androidx.compose.runtime.Composable public static void LazyLayout(androidx.compose.foundation.lazy.layout.LazyLayoutItemProvider itemProvider, optional androidx.compose.ui.Modifier modifier, optional androidx.compose.foundation.lazy.layout.LazyLayoutPrefetchState? prefetchState, kotlin.jvm.functions.Function2<? super androidx.compose.foundation.lazy.layout.LazyLayoutMeasureScope,? super androidx.compose.ui.unit.Constraints,? extends androidx.compose.ui.layout.MeasureResult> measurePolicy);
+ method @Deprecated @SuppressCompatibility @androidx.compose.foundation.ExperimentalFoundationApi @androidx.compose.runtime.Composable public static void LazyLayout(androidx.compose.foundation.lazy.layout.LazyLayoutItemProvider itemProvider, optional androidx.compose.ui.Modifier modifier, optional androidx.compose.foundation.lazy.layout.LazyLayoutPrefetchState? prefetchState, kotlin.jvm.functions.Function2<? super androidx.compose.foundation.lazy.layout.LazyLayoutMeasureScope,? super androidx.compose.ui.unit.Constraints,? extends androidx.compose.ui.layout.MeasureResult> measurePolicy);
+ method @SuppressCompatibility @androidx.compose.foundation.ExperimentalFoundationApi @androidx.compose.runtime.Composable public static void LazyLayout(kotlin.jvm.functions.Function0<? extends androidx.compose.foundation.lazy.layout.LazyLayoutItemProvider> itemProvider, optional androidx.compose.ui.Modifier modifier, optional androidx.compose.foundation.lazy.layout.LazyLayoutPrefetchState? prefetchState, kotlin.jvm.functions.Function2<? super androidx.compose.foundation.lazy.layout.LazyLayoutMeasureScope,? super androidx.compose.ui.unit.Constraints,? extends androidx.compose.ui.layout.MeasureResult> measurePolicy);
}
@SuppressCompatibility @androidx.compose.foundation.ExperimentalFoundationApi @androidx.compose.runtime.Stable public sealed interface LazyLayoutMeasureScope extends androidx.compose.ui.layout.MeasureScope {
diff --git a/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/layout/LazyLayoutStateRestorationTest.kt b/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/layout/LazyLayoutStateRestorationTest.kt
index d05d1f1..eab253b 100644
--- a/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/layout/LazyLayoutStateRestorationTest.kt
+++ b/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/layout/LazyLayoutStateRestorationTest.kt
@@ -299,20 +299,19 @@
indexToKey: (Int) -> Any = { getDefaultLazyLayoutKey(it) },
content: @Composable (Int) -> Unit
) {
- LazyLayout(
- itemProvider = remember(itemCount, indexToKey, content as Any) {
- object : LazyLayoutItemProvider {
- override val itemCount: Int = itemCount()
+ val provider = remember(itemCount, indexToKey, content as Any) {
+ object : LazyLayoutItemProvider {
+ override val itemCount: Int = itemCount()
- @Composable
- override fun Item(index: Int, key: Any) {
- content(index)
- }
-
- override fun getKey(index: Int) = indexToKey(index)
+ @Composable
+ override fun Item(index: Int, key: Any) {
+ content(index)
}
+
+ override fun getKey(index: Int) = indexToKey(index)
}
- ) { constraints ->
+ }
+ LazyLayout(itemProvider = { provider }) { constraints ->
val placeables = mutableListOf<Placeable>()
repeat(itemCount()) { index ->
if (itemIsVisible(index)) {
diff --git a/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/layout/LazyLayoutTest.kt b/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/layout/LazyLayoutTest.kt
index 7cedc56..cd762bf 100644
--- a/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/layout/LazyLayoutTest.kt
+++ b/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/layout/LazyLayoutTest.kt
@@ -163,7 +163,7 @@
LazyLayout(itemProvider) {
val constraints = Constraints.fixed(100, 100)
val items = mutableListOf<Placeable>()
- repeat(itemProvider.itemCount) { index ->
+ repeat(itemProvider().itemCount) { index ->
items.addAll(measure(index, constraints))
}
layout(100, 100) {
@@ -204,7 +204,7 @@
LazyLayout(itemProvider) {
val constraints = Constraints.fixed(100, 100)
val items = mutableListOf<Placeable>()
- repeat(itemProvider.itemCount) { index ->
+ repeat(itemProvider().itemCount) { index ->
items.addAll(measure(index, constraints))
}
layout(100, 100) {
@@ -463,7 +463,7 @@
override fun getKey(index: Int) = stateList[index]
}
rule.setContent {
- LazyLayout(itemProvider) { constraint ->
+ LazyLayout({ itemProvider }) { constraint ->
measure(0, constraint)
layout(100, 100) {}
}
@@ -483,8 +483,8 @@
private fun itemProvider(
itemCount: () -> Int,
itemContent: @Composable (Int) -> Unit
- ): LazyLayoutItemProvider {
- return object : LazyLayoutItemProvider {
+ ): () -> LazyLayoutItemProvider {
+ val provider = object : LazyLayoutItemProvider {
@Composable
override fun Item(index: Int, key: Any) {
itemContent(index)
@@ -492,5 +492,6 @@
override val itemCount: Int get() = itemCount()
}
+ return { provider }
}
}
diff --git a/compose/foundation/foundation/src/commonMain/kotlin/androidx/compose/foundation/lazy/layout/LazyLayout.kt b/compose/foundation/foundation/src/commonMain/kotlin/androidx/compose/foundation/lazy/layout/LazyLayout.kt
index 3ad7f4f..6c08e89 100644
--- a/compose/foundation/foundation/src/commonMain/kotlin/androidx/compose/foundation/lazy/layout/LazyLayout.kt
+++ b/compose/foundation/foundation/src/commonMain/kotlin/androidx/compose/foundation/lazy/layout/LazyLayout.kt
@@ -37,6 +37,12 @@
* @param prefetchState allows to schedule items for prefetching
* @param measurePolicy Measure policy which allows to only compose and measure needed items.
*/
+@Deprecated(
+ message = "Use an overload accepting a lambda prodicing an item provider instead",
+ replaceWith = ReplaceWith(
+ "LazyLayout({ itemProvider }, modifier, prefetchState, measurePolicy)"
+ )
+)
@ExperimentalFoundationApi
@Composable
fun LazyLayout(
@@ -48,9 +54,19 @@
LazyLayout({ itemProvider }, modifier, prefetchState, measurePolicy)
}
+/**
+ * A layout that only composes and lays out currently needed items. Can be used to build
+ * efficient scrollable layouts.
+ *
+ * @param itemProvider lambda producing an item provider containing all the needed info about
+ * the items which could be used to compose and measure items as part of [measurePolicy].
+ * @param modifier to apply on the layout
+ * @param prefetchState allows to schedule items for prefetching
+ * @param measurePolicy Measure policy which allows to only compose and measure needed items.
+ */
@ExperimentalFoundationApi
@Composable
-internal fun LazyLayout(
+fun LazyLayout(
itemProvider: () -> LazyLayoutItemProvider,
modifier: Modifier = Modifier,
prefetchState: LazyLayoutPrefetchState? = null,
diff --git a/tv/tv-foundation/src/main/java/androidx/tv/foundation/lazy/grid/LazyGrid.kt b/tv/tv-foundation/src/main/java/androidx/tv/foundation/lazy/grid/LazyGrid.kt
index b95b687..5cf5964 100644
--- a/tv/tv-foundation/src/main/java/androidx/tv/foundation/lazy/grid/LazyGrid.kt
+++ b/tv/tv-foundation/src/main/java/androidx/tv/foundation/lazy/grid/LazyGrid.kt
@@ -127,7 +127,7 @@
),
prefetchState = state.prefetchState,
measurePolicy = measurePolicy,
- itemProvider = itemProvider
+ itemProvider = { itemProvider }
)
}
diff --git a/tv/tv-foundation/src/main/java/androidx/tv/foundation/lazy/list/LazyList.kt b/tv/tv-foundation/src/main/java/androidx/tv/foundation/lazy/list/LazyList.kt
index 224af43..34254cc 100644
--- a/tv/tv-foundation/src/main/java/androidx/tv/foundation/lazy/list/LazyList.kt
+++ b/tv/tv-foundation/src/main/java/androidx/tv/foundation/lazy/list/LazyList.kt
@@ -131,7 +131,7 @@
),
prefetchState = state.prefetchState,
measurePolicy = measurePolicy,
- itemProvider = itemProvider
+ itemProvider = { itemProvider }
)
}
