Obsolete
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po...@google.com
Project: platform/frameworks/support
Branch: androidx-master-dev
commit fcf76b3241844f18106d6e850004952046d4bfb6
Author: Leland Richardson <lelandr@google.com>
Date: Wed May 13 16:58:59 2020
Deprecate @Model
Relnote: “
@Model annotation is now deprecated. Use state and mutableStateOf as alternatives. This deprecation decision was reached after much careful discussion.
Justification
=============
Rationale includes but is not limited to:
- Reduces API surface area and concepts we need to teach
- More closely aligns with other comparable toolkits (Swift UI, React, Flutter)
- Reversible decision. We can always bring @Model back later.
- Removes corner-case usage and difficult to answer questions about configuring @Model as things we need to handle
- @Model data classes, equals, hashcode, etc.
- How do I have some properties “observed” and others not?
- How do I specify structural vs. referential equality to be used in observation?
- Reduces “magic” in the system. Would reduce the likelihood of someone assuming system was smarter than it is (ie, it knowing how to diff a list)
- Makes the granularity of observation more intuitive.
- Improves refactorability from variable -> property on class
- Potentially opens up possibilities to do hand-crafted State-specific optimizations
- More closely aligns with the rest of the ecosystem and reduces ambiguity towards immutable or us “embracing mutable state”
Migration Notes
===============
Almost all existing usages of @Model are fairly trivially transformed in one of two ways. The example below has a @Model class with two properties just for the sake of example, and has it being used in a composable.
```
@Model class Position(
var x: Int,
var y: Int
)
@Composable fun Example() {
var p = remember { Position(0, 0) }
PositionChanger(
position=p,
onXChange={ p.x = it }
onYChange={ p.y = it }
)
}
```
Alternative 1: Use State<OriginalClass> and create copies.
----------------------------------------------------------
This approach is made easier with Kotlin’s data classes. Essentially, make all previously `var` properties into `val` properties of a data class, and then use `state` instead of `remember`, and assign the state value to cloned copies of the original using the data class `copy(...)` convenience method.
It’s important to note that this approach only works when the only mutations to that class were done in the same scope that the `State` instance is created. If the class is internally mutating itself outside of the scope of usage, and you are relying on the observation of that, then the next approach is the one you will want to use.
```
data class Position(
val x: Int,
val y: Int
)
@Composable fun Example() {
var p by state { Position(0, 0) }
PositionChanger(
position=p,
onXChange={ p = p.copy(x=it) }
onYChange={ p = p.copy(y=it) }
)
}
```
Alternative 2: Use mutableStateOf and property delegates
--------------------------------------------------------
This approach is made easier with Kotlin’s property delegates and the `mutableStateOf` API which allows you to create MutableState instances outside of composition. Essentially, replace all `var` properties of the original class with `var` properties with `mutableStateOf` as their property delegate. This has the advantage that the usage of the class will not change at all, only the internal implementation of it. The behavior is not completely identical to the original example though, as each property is now observed/subscribed to individually, so the recompositions you see after this refactor could be more narrow (a good thing).
```
class Position(x: Int, y: Int) {
var x by mutableStateOf(x)
var y by mutableStateOf(y)
}
// source of Example is identical to original
@Composable fun Example() {
var p = remember { Position(0, 0) }
PositionChanger(
position=p,
onXChange={ p.x = it }
onYChange={ p.y = it }
)
}
```
“
Bug: 156546430
Bug: 152993135
Bug: 152050010
Bug: 148866188
Bug: 148422703
Bug: 148394427
Bug: 146362815
Bug: 146342522
Bug: 143413369
Bug: 135715219
Bug: 126418732
Bug: 147088098
Bug: 143263925
Bug: 139653744
Change-Id: I409e8c158841eae1dd548b33f1ec80bb609cba31
M compose/compose-compiler-hosted/integration-tests/src/test/java/androidx/compose/plugins/kotlin/frames/FrameDiagnosticTests.kt
M compose/compose-runtime/api/0.1.0-dev12.txt
M compose/compose-runtime/api/current.txt
M compose/compose-runtime/api/public_plus_experimental_0.1.0-dev12.txt
M compose/compose-runtime/api/public_plus_experimental_current.txt
M compose/compose-runtime/api/restricted_0.1.0-dev12.txt
M compose/compose-runtime/api/restricted_current.txt
M compose/compose-runtime/compose-runtime-benchmark/src/androidTest/java/androidx/compose/benchmark/ComposeBenchmark.kt
M compose/compose-runtime/compose-runtime-benchmark/src/androidTest/java/androidx/compose/benchmark/SiblingBenchmark.kt
M compose/compose-runtime/compose-runtime-benchmark/src/androidTest/java/androidx/compose/benchmark/dbmonster/DbMonster.kt
M compose/compose-runtime/compose-runtime-benchmark/src/androidTest/java/androidx/compose/benchmark/realworld4/RealWorld4_DataModels.kt
M compose/compose-runtime/samples/src/main/java/androidx/compose/samples/ModelSamples.kt
M compose/compose-runtime/src/commonMain/kotlin/androidx/compose/FrameManager.kt
M compose/compose-runtime/src/commonMain/kotlin/androidx/compose/Model.kt
M compose/compose-runtime/src/commonMain/kotlin/androidx/compose/MutableState.kt
M compose/compose-runtime/src/commonMain/kotlin/androidx/compose/Observe.kt
M compose/compose-runtime/src/commonMain/kotlin/androidx/compose/Recompose.kt
M compose/compose-runtime/src/commonMain/kotlin/androidx/compose/StableMarker.kt
M ui/integration-tests/benchmark/src/androidTest/java/androidx/ui/benchmark/test/ModelObserverBenchmark.kt
M ui/integration-tests/benchmark/src/androidTest/java/androidx/ui/benchmark/test/RadioGroupBenchmark.kt
M ui/integration-tests/demos/src/main/java/androidx/ui/demos/DemoColorPalette.kt
M ui/integration-tests/src/main/java/androidx/ui/integration/test/foundation/RectsInColumnSharedModelTestCase.kt
M ui/ui-android-view/integration-tests/android-view-demos/src/main/java/androidx/ui/androidview/demos/WebComponentActivity.kt
M ui/ui-animation/src/main/java/androidx/ui/animation/AnimatedValueEffects.kt
M ui/ui-animation/src/main/java/androidx/ui/animation/Transition.kt
M ui/ui-core/src/androidTest/java/androidx/ui/core/test/AndroidLayoutDrawTest.kt
M ui/ui-core/src/androidTest/java/androidx/ui/core/test/AndroidViewCompatTest.kt
M ui/ui-core/src/androidTest/java/androidx/ui/core/test/ClipTest.kt
M ui/ui-core/src/androidTest/java/androidx/ui/core/test/DrawShadowTest.kt
M ui/ui-core/src/androidTest/java/androidx/ui/core/test/ModelReadsTest.kt
M ui/ui-core/src/androidTest/java/androidx/ui/core/test/OpacityTest.kt
D ui/ui-core/src/androidTest/java/androidx/ui/core/test/ValueModel.kt
M ui/ui-core/src/androidTest/java/androidx/ui/core/test/WithConstraintsTest.kt
M ui/ui-core/src/androidTest/java/androidx/ui/res/ResourcesTest.kt
M ui/ui-core/src/androidTest/java/androidx/ui/semantics/SemanticsTests.kt
M ui/ui-core/src/main/java/androidx/ui/core/ModelObserver.kt
M ui/ui-core/src/main/java/androidx/ui/res/Resources.kt
M ui/ui-core/src/test/java/androidx/ui/core/selection/SelectionManagerDragTest.kt
M ui/ui-core/src/test/java/androidx/ui/core/selection/SelectionManagerLongPressDragTest.kt
M ui/ui-core/src/test/java/androidx/ui/core/selection/SelectionManagerTest.kt
M ui/ui-foundation/src/androidTest/java/androidx/ui/foundation/DeterminateProgressTest.kt
M ui/ui-layout/src/androidTest/java/androidx/ui/layout/test/ContainerTest.kt
M ui/ui-layout/src/androidTest/java/androidx/ui/layout/test/OnPositionedTest.kt
M ui/ui-material/api/0.1.0-dev12.txt
M ui/ui-material/api/current.txt
M ui/ui-material/api/public_plus_experimental_0.1.0-dev12.txt
M ui/ui-material/api/public_plus_experimental_current.txt
M ui/ui-material/api/restricted_0.1.0-dev12.txt
M ui/ui-material/api/restricted_current.txt
M ui/ui-material/integration-tests/material-demos/src/main/java/androidx/ui/material/demos/DynamicThemeActivity.kt
M ui/ui-material/src/androidTest/java/androidx/ui/material/DrawerTest.kt
M ui/ui-material/src/androidTest/java/androidx/ui/material/ProgressIndicatorTest.kt
M ui/ui-material/src/androidTest/java/androidx/ui/material/RadioGroupUiTest.kt
M ui/ui-material/src/main/java/androidx/ui/material/Color.kt
M ui/ui-material/src/main/java/androidx/ui/material/Scaffold.kt
M ui/ui-test/src/androidTest/java/androidx/ui/test/AndroidComposeTestCaseRunnerTest.kt
M ui/ui-test/src/androidTest/java/androidx/ui/test/MultipleComposeRootsTest.kt
M ui/ui-text/src/main/java/androidx/ui/text/CoreText.kt
M ui/ui-text/src/main/java/androidx/ui/text/CoreTextField.kt
https://android-review.googlesource.com/1311293
Branch: androidx-master-dev
commit fcf76b3241844f18106d6e850004952046d4bfb6
Author: Leland Richardson <lelandr@google.com>
Date: Wed May 13 16:58:59 2020
Deprecate @Model
Relnote: “
@Model annotation is now deprecated. Use state and mutableStateOf as alternatives. This deprecation decision was reached after much careful discussion.
Justification
=============
Rationale includes but is not limited to:
- Reduces API surface area and concepts we need to teach
- More closely aligns with other comparable toolkits (Swift UI, React, Flutter)
- Reversible decision. We can always bring @Model back later.
- Removes corner-case usage and difficult to answer questions about configuring @Model as things we need to handle
- @Model data classes, equals, hashcode, etc.
- How do I have some properties “observed” and others not?
- How do I specify structural vs. referential equality to be used in observation?
- Reduces “magic” in the system. Would reduce the likelihood of someone assuming system was smarter than it is (ie, it knowing how to diff a list)
- Makes the granularity of observation more intuitive.
- Improves refactorability from variable -> property on class
- Potentially opens up possibilities to do hand-crafted State-specific optimizations
- More closely aligns with the rest of the ecosystem and reduces ambiguity towards immutable or us “embracing mutable state”
Migration Notes
===============
Almost all existing usages of @Model are fairly trivially transformed in one of two ways. The example below has a @Model class with two properties just for the sake of example, and has it being used in a composable.
```
@Model class Position(
var x: Int,
var y: Int
)
@Composable fun Example() {
var p = remember { Position(0, 0) }
PositionChanger(
position=p,
onXChange={ p.x = it }
onYChange={ p.y = it }
)
}
```
Alternative 1: Use State<OriginalClass> and create copies.
----------------------------------------------------------
This approach is made easier with Kotlin’s data classes. Essentially, make all previously `var` properties into `val` properties of a data class, and then use `state` instead of `remember`, and assign the state value to cloned copies of the original using the data class `copy(...)` convenience method.
It’s important to note that this approach only works when the only mutations to that class were done in the same scope that the `State` instance is created. If the class is internally mutating itself outside of the scope of usage, and you are relying on the observation of that, then the next approach is the one you will want to use.
```
data class Position(
val x: Int,
val y: Int
)
@Composable fun Example() {
var p by state { Position(0, 0) }
PositionChanger(
position=p,
onXChange={ p = p.copy(x=it) }
onYChange={ p = p.copy(y=it) }
)
}
```
Alternative 2: Use mutableStateOf and property delegates
--------------------------------------------------------
This approach is made easier with Kotlin’s property delegates and the `mutableStateOf` API which allows you to create MutableState instances outside of composition. Essentially, replace all `var` properties of the original class with `var` properties with `mutableStateOf` as their property delegate. This has the advantage that the usage of the class will not change at all, only the internal implementation of it. The behavior is not completely identical to the original example though, as each property is now observed/subscribed to individually, so the recompositions you see after this refactor could be more narrow (a good thing).
```
class Position(x: Int, y: Int) {
var x by mutableStateOf(x)
var y by mutableStateOf(y)
}
// source of Example is identical to original
@Composable fun Example() {
var p = remember { Position(0, 0) }
PositionChanger(
position=p,
onXChange={ p.x = it }
onYChange={ p.y = it }
)
}
```
“
Bug: 156546430
Bug: 152993135
Bug: 152050010
Bug: 148866188
Bug: 148422703
Bug: 148394427
Bug: 146362815
Bug: 146342522
Bug: 143413369
Bug: 135715219
Bug: 126418732
Bug: 147088098
Bug: 143263925
Bug: 139653744
Change-Id: I409e8c158841eae1dd548b33f1ec80bb609cba31
M compose/compose-compiler-hosted/integration-tests/src/test/java/androidx/compose/plugins/kotlin/frames/FrameDiagnosticTests.kt
M compose/compose-runtime/api/0.1.0-dev12.txt
M compose/compose-runtime/api/current.txt
M compose/compose-runtime/api/public_plus_experimental_0.1.0-dev12.txt
M compose/compose-runtime/api/public_plus_experimental_current.txt
M compose/compose-runtime/api/restricted_0.1.0-dev12.txt
M compose/compose-runtime/api/restricted_current.txt
M compose/compose-runtime/compose-runtime-benchmark/src/androidTest/java/androidx/compose/benchmark/ComposeBenchmark.kt
M compose/compose-runtime/compose-runtime-benchmark/src/androidTest/java/androidx/compose/benchmark/SiblingBenchmark.kt
M compose/compose-runtime/compose-runtime-benchmark/src/androidTest/java/androidx/compose/benchmark/dbmonster/DbMonster.kt
M compose/compose-runtime/compose-runtime-benchmark/src/androidTest/java/androidx/compose/benchmark/realworld4/RealWorld4_DataModels.kt
M compose/compose-runtime/samples/src/main/java/androidx/compose/samples/ModelSamples.kt
M compose/compose-runtime/src/commonMain/kotlin/androidx/compose/FrameManager.kt
M compose/compose-runtime/src/commonMain/kotlin/androidx/compose/Model.kt
M compose/compose-runtime/src/commonMain/kotlin/androidx/compose/MutableState.kt
M compose/compose-runtime/src/commonMain/kotlin/androidx/compose/Observe.kt
M compose/compose-runtime/src/commonMain/kotlin/androidx/compose/Recompose.kt
M compose/compose-runtime/src/commonMain/kotlin/androidx/compose/StableMarker.kt
M ui/integration-tests/benchmark/src/androidTest/java/androidx/ui/benchmark/test/ModelObserverBenchmark.kt
M ui/integration-tests/benchmark/src/androidTest/java/androidx/ui/benchmark/test/RadioGroupBenchmark.kt
M ui/integration-tests/demos/src/main/java/androidx/ui/demos/DemoColorPalette.kt
M ui/integration-tests/src/main/java/androidx/ui/integration/test/foundation/RectsInColumnSharedModelTestCase.kt
M ui/ui-android-view/integration-tests/android-view-demos/src/main/java/androidx/ui/androidview/demos/WebComponentActivity.kt
M ui/ui-animation/src/main/java/androidx/ui/animation/AnimatedValueEffects.kt
M ui/ui-animation/src/main/java/androidx/ui/animation/Transition.kt
M ui/ui-core/src/androidTest/java/androidx/ui/core/test/AndroidLayoutDrawTest.kt
M ui/ui-core/src/androidTest/java/androidx/ui/core/test/AndroidViewCompatTest.kt
M ui/ui-core/src/androidTest/java/androidx/ui/core/test/ClipTest.kt
M ui/ui-core/src/androidTest/java/androidx/ui/core/test/DrawShadowTest.kt
M ui/ui-core/src/androidTest/java/androidx/ui/core/test/ModelReadsTest.kt
M ui/ui-core/src/androidTest/java/androidx/ui/core/test/OpacityTest.kt
D ui/ui-core/src/androidTest/java/androidx/ui/core/test/ValueModel.kt
M ui/ui-core/src/androidTest/java/androidx/ui/core/test/WithConstraintsTest.kt
M ui/ui-core/src/androidTest/java/androidx/ui/res/ResourcesTest.kt
M ui/ui-core/src/androidTest/java/androidx/ui/semantics/SemanticsTests.kt
M ui/ui-core/src/main/java/androidx/ui/core/ModelObserver.kt
M ui/ui-core/src/main/java/androidx/ui/res/Resources.kt
M ui/ui-core/src/test/java/androidx/ui/core/selection/SelectionManagerDragTest.kt
M ui/ui-core/src/test/java/androidx/ui/core/selection/SelectionManagerLongPressDragTest.kt
M ui/ui-core/src/test/java/androidx/ui/core/selection/SelectionManagerTest.kt
M ui/ui-foundation/src/androidTest/java/androidx/ui/foundation/DeterminateProgressTest.kt
M ui/ui-layout/src/androidTest/java/androidx/ui/layout/test/ContainerTest.kt
M ui/ui-layout/src/androidTest/java/androidx/ui/layout/test/OnPositionedTest.kt
M ui/ui-material/api/0.1.0-dev12.txt
M ui/ui-material/api/current.txt
M ui/ui-material/api/public_plus_experimental_0.1.0-dev12.txt
M ui/ui-material/api/public_plus_experimental_current.txt
M ui/ui-material/api/restricted_0.1.0-dev12.txt
M ui/ui-material/api/restricted_current.txt
M ui/ui-material/integration-tests/material-demos/src/main/java/androidx/ui/material/demos/DynamicThemeActivity.kt
M ui/ui-material/src/androidTest/java/androidx/ui/material/DrawerTest.kt
M ui/ui-material/src/androidTest/java/androidx/ui/material/ProgressIndicatorTest.kt
M ui/ui-material/src/androidTest/java/androidx/ui/material/RadioGroupUiTest.kt
M ui/ui-material/src/main/java/androidx/ui/material/Color.kt
M ui/ui-material/src/main/java/androidx/ui/material/Scaffold.kt
M ui/ui-test/src/androidTest/java/androidx/ui/test/AndroidComposeTestCaseRunnerTest.kt
M ui/ui-test/src/androidTest/java/androidx/ui/test/MultipleComposeRootsTest.kt
M ui/ui-text/src/main/java/androidx/ui/text/CoreText.kt
M ui/ui-text/src/main/java/androidx/ui/text/CoreTextField.kt
pa...@google.com
There does not seem to be any improvement in that particular benchmark.
I was looking based on build ab/6852971
Attached screenshots of all the devices + one without the noisy ones. The point where is the cross-hair is the place with the build.
You can also take a look yourself here:
To pan and zoom please use the keyboard shortcuts (displayed on the left side of the UI with blue text)
ap...@google.com
Project: platform/frameworks/support
Branch: androidx-master-dev
commit e7bf661e6433826be9ab75256bb2ca7ff259304d
Author: Mihai Popa <popam@google.com>
Date: Fri Sep 25 11:15:39 2020
Refactor Box for improved performance
The CL:
- updates the implementation of Box to reduce allocations and the number
of children traversals
- makes Box inline
- adds NestedBoxesBenchmark, which shows a 25% improvement after the
changes above
Relnote: Box was made an inline function.
Bug: 155056091
Test: ran BoxTest and NestedBoxesBenchmark
Change-Id: Ibce0c1940173f06c030fd1115b9badb692ceb05a
M compose/foundation/foundation-layout/api/current.txt
M compose/foundation/foundation-layout/api/public_plus_experimental_current.txt
M compose/foundation/foundation-layout/api/restricted_current.txt
M compose/foundation/foundation-layout/src/commonMain/kotlin/androidx/compose/foundation/layout/Box.kt
A compose/integration-tests/benchmark/src/androidTest/java/androidx/ui/benchmark/test/NestedBoxesBenchmark.kt
A compose/integration-tests/src/main/java/androidx/ui/integration/test/foundation/NestedBoxesTestCase.kt
M compose/material/material/src/commonMain/kotlin/androidx/compose/material/Swipeable.kt
M compose/ui/ui/src/androidAndroidTest/kotlin/androidx/compose/ui/layout/SubcomposeLayoutTest.kt
M ui/ui-tooling/src/androidTest/java/androidx/ui/tooling/BoundsTest.kt
M ui/ui-tooling/src/androidTest/java/androidx/ui/tooling/ModifierInfoTest.kt
https://android-review.googlesource.com/1439051
Branch: androidx-master-dev
commit e7bf661e6433826be9ab75256bb2ca7ff259304d
Author: Mihai Popa <popam@google.com>
Date: Fri Sep 25 11:15:39 2020
Refactor Box for improved performance
The CL:
- updates the implementation of Box to reduce allocations and the number
of children traversals
- makes Box inline
- adds NestedBoxesBenchmark, which shows a 25% improvement after the
changes above
Relnote: Box was made an inline function.
Bug: 155056091
Test: ran BoxTest and NestedBoxesBenchmark
Change-Id: Ibce0c1940173f06c030fd1115b9badb692ceb05a
M compose/foundation/foundation-layout/api/current.txt
M compose/foundation/foundation-layout/api/public_plus_experimental_current.txt
M compose/foundation/foundation-layout/api/restricted_current.txt
M compose/foundation/foundation-layout/src/commonMain/kotlin/androidx/compose/foundation/layout/Box.kt
A compose/integration-tests/benchmark/src/androidTest/java/androidx/ui/benchmark/test/NestedBoxesBenchmark.kt
A compose/integration-tests/src/main/java/androidx/ui/integration/test/foundation/NestedBoxesTestCase.kt
M compose/material/material/src/commonMain/kotlin/androidx/compose/material/Swipeable.kt
M compose/ui/ui/src/androidAndroidTest/kotlin/androidx/compose/ui/layout/SubcomposeLayoutTest.kt
M ui/ui-tooling/src/androidTest/java/androidx/ui/tooling/BoundsTest.kt
M ui/ui-tooling/src/androidTest/java/androidx/ui/tooling/ModifierInfoTest.kt
po...@google.com
Since this is an old regression, and many performance improvements have happened in the past months, I will close this as obsolete. Nonetheless, I am a bit surprised my CL did not improve that benchmark.
Description
Given we plan the Box to be foundational component to build things with, we should probably see what we can do here.
Alert on dashboard:
CLs in build: aosp/1287601
Note: the shared model benchmark surfaces things like this more because it recomposes all the rectangles even when one changes (because they share reference to one model entry from the foreach loop)