LazyGridScopeImpl.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.lazy.GridItemSpan
import androidx.compose.foundation.lazy.LazyGridItemSpanScope
import androidx.compose.foundation.lazy.LazyGridScope
import androidx.compose.foundation.lazy.layout.MutableIntervalList
import androidx.compose.runtime.Composable
@OptIn(ExperimentalFoundationApi::class)
internal class LazyGridScopeImpl : LazyGridScope {
internal val intervals = MutableIntervalList<LazyGridIntervalContent>()
internal var hasCustomSpans = false
private val DefaultSpan: LazyGridItemSpanScope.(Int) -> GridItemSpan = { GridItemSpan(1) }
override fun item(
key: Any?,
span: (LazyGridItemSpanScope.() -> GridItemSpan)?,
content: @Composable () -> Unit
) {
intervals.add(
1,
LazyGridIntervalContent(
key = key?.let { { key } },
span = span?.let { { span() } } ?: DefaultSpan,
content = { { content() } }
)
)
if (span != null) hasCustomSpans = true
}
override fun items(
count: Int,
key: ((index: Int) -> Any)?,
span: (LazyGridItemSpanScope.(Int) -> GridItemSpan)?,
itemContent: @Composable (index: Int) -> Unit
) {
intervals.add(
count,
LazyGridIntervalContent(
key = key,
span = span ?: DefaultSpan,
content = { { itemContent(it) } }
)
)
if (span != null) hasCustomSpans = true
}
}
@OptIn(ExperimentalFoundationApi::class)
internal class LazyGridIntervalContent(
val key: ((index: Int) -> Any)?,
val span: LazyGridItemSpanScope.(Int) -> GridItemSpan,
val content: (Int) -> (@Composable () -> Unit)
)