LazyListLayoutInfo.kt
/*
* Copyright 2020 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
/**
* Contains useful information about the currently displayed layout state of lazy lists like
* [LazyColumn] or [LazyRow]. For example you can get the list of currently displayed item.
*
* Use [LazyListState.layoutInfo] to retrieve this
*/
interface LazyListLayoutInfo {
/**
* The list of [LazyListItemInfo] representing all the currently visible items.
*/
val visibleItemsInfo: List<LazyListItemInfo>
/**
* The start offset of the layout's viewport. You can think of it as a minimum offset which
* would be visible. Usually it is 0, but it can be negative if a content padding was applied
* as the content displayed in the content padding area is still visible.
*
* You can use it to understand what items from [visibleItemsInfo] are fully visible.
*/
val viewportStartOffset: Int
/**
* The end offset of the layout's viewport. You can think of it as a maximum offset which
* would be visible. Usually it is a size of the lazy list container plus a content padding.
*
* You can use it to understand what items from [visibleItemsInfo] are fully visible.
*/
val viewportEndOffset: Int
/**
* The total count of items passed to [LazyColumn] or [LazyRow].
*/
val totalItemsCount: Int
}