LazySemantics.kt

/*
 * Copyright 2021 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package androidx.compose.foundation.lazy.grid

import androidx.compose.foundation.ExperimentalFoundationApi
import androidx.compose.foundation.gestures.animateScrollBy
import androidx.compose.foundation.lazy.layout.LazyLayoutSemanticState
import androidx.compose.runtime.Composable
import androidx.compose.runtime.remember
import androidx.compose.ui.semantics.CollectionInfo

@OptIn(ExperimentalFoundationApi::class)
@Composable
internal fun rememberLazyGridSemanticState(
    state: LazyGridState,
    reverseScrolling: Boolean
): LazyLayoutSemanticState =
    remember(state, reverseScrolling) {
        object : LazyLayoutSemanticState {
            override val currentPosition: Float
                get() = state.firstVisibleItemIndex + state.firstVisibleItemScrollOffset / 100_000f
            override val canScrollForward: Boolean
                get() = state.canScrollForward

            override suspend fun animateScrollBy(delta: Float) {
                state.animateScrollBy(delta)
            }

            override suspend fun scrollToItem(index: Int) {
                state.scrollToItem(index)
            }

            // TODO(popam): check if this is correct - it would be nice to provide correct columns
            override fun collectionInfo(): CollectionInfo =
                CollectionInfo(rowCount = -1, columnCount = -1)
        }
    }