Introduce MovableElementScenePicker (aa4ecae1) · Commits · e / os / android_frameworks_base

packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/TransitionDsl.kt

+26 −0

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		@@ -136,6 +136,7 @@ interface TransitionBuilder : PropertyTransformationBuilder {
		* @see DefaultElementScenePicker
		* @see HighestZIndexScenePicker
		* @see LowestZIndexScenePicker
		* @see MovableElementScenePicker
		*/
		interface ElementScenePicker {
		/**
		@@ -227,6 +228,31 @@ object LowestZIndexScenePicker : ElementScenePicker {
		}
		}

		/**
		* An [ElementScenePicker] that draws/composes elements in the scene we are transitioning to, iff
		* that scene is in [scenes].
		*
		* This picker can be useful for movable elements whose content size depends on its content (because
		* it wraps it) in at least one scene. That way, the target size of the MovableElement will be
		* computed in the scene we are going to and, given that this element was probably already composed
		* in the scene we are going from before starting the transition, the interpolated size of the
		* movable element during the transition should be correct.
		*
		* The downside of this picker is that the zIndex of the element when going from scene A to scene B
		* is not the same as when going from scene B to scene A, so it's not usable in situations where
		* z-ordering during the transition matters.
		*/
		class MovableElementScenePicker(private val scenes: Set<SceneKey>) : ElementScenePicker {
		override fun sceneDuringTransition(
		element: ElementKey,
		transition: TransitionState.Transition,
		fromSceneZIndex: Float,
		toSceneZIndex: Float,
		): SceneKey {
		return if (scenes.contains(transition.toScene)) transition.toScene else transition.fromScene
		}
		}

		/** The default [ElementScenePicker]. */
		val DefaultElementScenePicker = HighestZIndexScenePicker

packages/SystemUI/compose/scene/tests/src/com/android/compose/animation/scene/MovableElementScenePickerTest.kt

0 → 100644

+53 −0

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		/*
		* Copyright (C) 2024 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 com.android.compose.animation.scene

		import androidx.test.ext.junit.runners.AndroidJUnit4
		import com.google.common.truth.Truth.assertThat
		import org.junit.Test
		import org.junit.runner.RunWith

		@RunWith(AndroidJUnit4::class)
		class MovableElementScenePickerTest {
		@Test
		fun toSceneInScenes() {
		val picker = MovableElementScenePicker(scenes = setOf(TestScenes.SceneA, TestScenes.SceneB))
		assertThat(
		picker.sceneDuringTransition(
		TestElements.Foo,
		transition(from = TestScenes.SceneA, to = TestScenes.SceneB),
		fromSceneZIndex = 0f,
		toSceneZIndex = 1f,
		)
		)
		.isEqualTo(TestScenes.SceneB)
		}

		@Test
		fun toSceneNotInScenes() {
		val picker = MovableElementScenePicker(scenes = emptySet())
		assertThat(
		picker.sceneDuringTransition(
		TestElements.Foo,
		transition(from = TestScenes.SceneA, to = TestScenes.SceneB),
		fromSceneZIndex = 0f,
		toSceneZIndex = 1f,
		)
		)
		.isEqualTo(TestScenes.SceneA)
		}
		}

packages/SystemUI/compose/scene/tests/src/com/android/compose/animation/scene/SceneTransitionLayoutStateTest.kt

+0 −9

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		@@ -50,13 +50,4 @@ class SceneTransitionLayoutStateTest {
		assertThat(state.isTransitioning(to = TestScenes.SceneA)).isFalse()
		assertThat(state.isTransitioning(from = TestScenes.SceneA, to = TestScenes.SceneB)).isTrue()
		}

		private fun transition(from: SceneKey, to: SceneKey): TransitionState.Transition {
		return object : TransitionState.Transition(from, to) {
		override val currentScene: SceneKey = from
		override val progress: Float = 0f
		override val isInitiatedByUserInput: Boolean = false
		override val isUserInputOngoing: Boolean = false
		}
		}
		}

packages/SystemUI/compose/scene/tests/utils/src/com/android/compose/animation/scene/Transition.kt

0 → 100644

+33 −0

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		/*
		* Copyright (C) 2024 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 com.android.compose.animation.scene

		/** A utility to easily create a [TransitionState.Transition] in tests. */
		fun transition(
		from: SceneKey,
		to: SceneKey,
		progress: () -> Float = { 0f },
		isInitiatedByUserInput: Boolean = false,
		isUserInputOngoing: Boolean = false,
		): TransitionState.Transition {
		return object : TransitionState.Transition(from, to) {
		override val currentScene: SceneKey = from
		override val progress: Float = progress()
		override val isInitiatedByUserInput: Boolean = isInitiatedByUserInput
		override val isUserInputOngoing: Boolean = isUserInputOngoing
		}
		}