/*
* Copyright 2022 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.ui.layout
import androidx.compose.ui.ExperimentalComposeUiApi
import androidx.compose.ui.platform.InspectorInfo
import androidx.compose.ui.platform.InspectorValueInfo
import androidx.compose.ui.unit.Constraints
import androidx.compose.ui.unit.IntSize
/**
* IntermediateLayoutModifier is a [LayoutModifier] that will be skipped when
* looking ahead. During measure pass, [measure] will be invoked with the constraints from the
* look-ahead, as well as the target size.
*/
@ExperimentalComposeUiApi
internal interface IntermediateLayoutModifier : LayoutModifier {
var targetSize: IntSize
}
@OptIn(ExperimentalComposeUiApi::class)
internal class LookaheadIntermediateLayoutModifierImpl(
val measureBlock: MeasureScope.(
measurable: Measurable,
constraints: Constraints,
lookaheadSize: IntSize
) -> MeasureResult,
inspectorInfo: InspectorInfo.() -> Unit
) : IntermediateLayoutModifier, InspectorValueInfo(inspectorInfo) {
override var targetSize: IntSize = IntSize.Zero
override fun MeasureScope.measure(
measurable: Measurable,
constraints: Constraints
): MeasureResult =
measureBlock(measurable, constraints, targetSize)
override fun equals(other: Any?): Boolean {
if (this === other) return true
if (other !is LookaheadIntermediateLayoutModifierImpl) return false
return measureBlock == other.measureBlock && targetSize == other.targetSize
}
override fun hashCode(): Int {
return measureBlock.hashCode() * 31 + targetSize.hashCode()
}
}