SemanticsWrapper.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.ui.semantics
import androidx.compose.ui.geometry.MutableRect
import androidx.compose.ui.geometry.Offset
import androidx.compose.ui.geometry.Rect
import androidx.compose.ui.geometry.Size
import androidx.compose.ui.geometry.toRect
import androidx.compose.ui.layout.boundsInRoot
import androidx.compose.ui.layout.boundsInWindow
import androidx.compose.ui.layout.findRoot
import androidx.compose.ui.layout.positionInRoot
import androidx.compose.ui.node.DelegatingLayoutNodeWrapper
import androidx.compose.ui.node.HitTestResult
import androidx.compose.ui.node.LayoutNodeWrapper
import androidx.compose.ui.node.requireOwner
import androidx.compose.ui.unit.toSize
internal class SemanticsWrapper(
wrapped: LayoutNodeWrapper,
semanticsModifier: SemanticsModifier
) : DelegatingLayoutNodeWrapper<SemanticsModifier>(wrapped, semanticsModifier) {
val semanticsSize: Size
get() {
val measuredSize = measuredSize
if (!useMinimumTouchTarget) {
return measuredSize.toSize()
}
val minTouchTargetSize = minimumTouchTargetSize
val width = maxOf(measuredSize.width.toFloat(), minTouchTargetSize.width)
val height = maxOf(measuredSize.height.toFloat(), minTouchTargetSize.height)
return Size(width, height)
}
private val useMinimumTouchTarget: Boolean
get() = modifier.semanticsConfiguration.getOrNull(SemanticsActions.OnClick) != null
fun collapsedSemanticsConfiguration(): SemanticsConfiguration {
val nextSemantics = wrapped.nearestSemantics { true }
if (nextSemantics == null || modifier.semanticsConfiguration.isClearingSemantics) {
return modifier.semanticsConfiguration
}
val config = modifier.semanticsConfiguration.copy()
config.collapsePeer(nextSemantics.collapsedSemanticsConfiguration())
return config
}
override fun detach() {
super.detach()
layoutNode.owner?.onSemanticsChange()
}
override fun onModifierChanged() {
super.onModifierChanged()
layoutNode.owner?.onSemanticsChange()
}
override fun toString(): String {
return "${super.toString()} id: ${modifier.id} config: ${modifier.semanticsConfiguration}"
}
override fun hitTestSemantics(
pointerPosition: Offset,
hitSemanticsWrappers: HitTestResult<SemanticsWrapper>
) {
hitTestInMinimumTouchTarget(
pointerPosition,
hitSemanticsWrappers,
this
) {
// Also, keep looking to see if we also might hit any children.
// This avoids checking layer bounds twice as when we call super.hitTest()
val positionInWrapped = wrapped.fromParentPosition(pointerPosition)
wrapped.hitTestSemantics(positionInWrapped, hitSemanticsWrappers)
}
}
fun semanticsPositionInRoot(): Offset {
if (!useMinimumTouchTarget) {
return positionInRoot()
}
check(isAttached) { ExpectAttachedLayoutCoordinates }
val root = findRoot()
val padding = calculateMinimumTouchTargetPadding(minimumTouchTargetSize)
val left = -padding.width
val top = -padding.height
return root.localPositionOf(this, Offset(left, top))
}
fun semanticsPositionInWindow(): Offset {
val positionInRoot = semanticsPositionInRoot()
return layoutNode.requireOwner().calculatePositionInWindow(positionInRoot)
}
fun semanticsBoundsInRoot(): Rect {
if (!useMinimumTouchTarget) {
return boundsInRoot()
}
return calculateBoundsInRoot().toRect()
}
fun semanticsBoundsInWindow(): Rect {
if (!useMinimumTouchTarget) {
return boundsInWindow()
}
val bounds = calculateBoundsInRoot()
val root = findRoot()
val topLeft = root.localToWindow(Offset(bounds.left, bounds.top))
val topRight = root.localToWindow(Offset(bounds.right, bounds.top))
val bottomRight = root.localToWindow(Offset(bounds.right, bounds.bottom))
val bottomLeft = root.localToWindow(Offset(bounds.left, bounds.bottom))
val left = minOf(topLeft.x, topRight.x, bottomLeft.x, bottomRight.x)
val top = minOf(topLeft.y, topRight.y, bottomLeft.y, bottomRight.y)
val right = maxOf(topLeft.x, topRight.x, bottomLeft.x, bottomRight.x)
val bottom = maxOf(topLeft.y, topRight.y, bottomLeft.y, bottomRight.y)
return Rect(left, top, right, bottom)
}
private fun calculateBoundsInRoot(): MutableRect {
check(isAttached) { ExpectAttachedLayoutCoordinates }
val root = findRoot()
val bounds = rectCache
val padding = calculateMinimumTouchTargetPadding(minimumTouchTargetSize)
bounds.left = -padding.width
bounds.top = -padding.height
bounds.right = measuredWidth + padding.width
bounds.bottom = measuredHeight + padding.height
var wrapper: LayoutNodeWrapper = this
while (wrapper !== root) {
wrapper.rectInParent(bounds, true)
if (bounds.isEmpty) {
bounds.set(0f, 0f, 0f, 0f)
return bounds
}
wrapper = wrapper.wrappedBy!!
}
return bounds
}
}