design(home) : use enterAlwaysScrollBehavior for the RoomListFiltersView

libraries/designsystem/src/main/kotlin/io/element/android/libraries/designsystem/components/TopAppBarScrollBehaviorLayout.kt

@@ -0,0 +1,54 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.designsystem.components
+
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.Surface
+import androidx.compose.material3.TopAppBarScrollBehavior
+import androidx.compose.material3.contentColorFor
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.UiComposable
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.layout.Layout
+import io.element.android.compound.theme.ElementTheme
+
+/**
+ * A layout that measures its content to set the height offset limit of a [TopAppBarScrollBehavior].
+ * It places the content according to the current height offset of the scroll behavior.
+ *
+ */
+@ExperimentalMaterial3Api
+@Composable
+fun TopAppBarScrollBehaviorLayout(
+    scrollBehavior: TopAppBarScrollBehavior,
+    modifier: Modifier = Modifier,
+    backgroundColor: Color = ElementTheme.colors.bgCanvasDefault,
+    contentColor: Color = contentColorFor(backgroundColor),
+    content: @Composable @UiComposable () -> Unit,
+) {
+    Surface(
+        modifier = modifier,
+        color = backgroundColor,
+        contentColor = contentColor
+    ) {
+        Layout(
+            content = content,
+            measurePolicy = { measurables, constraints ->
+                val placeable = measurables.first().measure(constraints)
+                val contentHeight = placeable.height.toFloat()
+                scrollBehavior.state.heightOffsetLimit = -contentHeight
+                val heightOffset = scrollBehavior.state.heightOffset
+                val layoutHeight = (contentHeight + heightOffset).toInt()
+                layout(placeable.width, layoutHeight) {
+                    placeable.place(0, heightOffset.toInt())
+                }
+            }
+        )
+    }
+}