NavGraphBuilder.dialog [206465487]

Fixed

Bug

Status Update

No update yet.

Description

ja...@deepl.com

created issue #1

Nov 16, 2021 02:51PM

Component used: Navigation

Version used: 2.4.0-beta02

Devices/Android versions reproduced on: Every device

I'm using Compose with the navigation components. I inject a ViewModel via Hilt.

I navigate with the NavGraphBuilder.composable() extension, which works.

When I open my composable within a Dialog via the NavGraphBuilder.dialog() extension I run into the following problem:

Closing the dialog with the system back button works. When I call navController.popBackstack() this exception occurs and the app crashes:

java.lang.IllegalStateException: You cannot access the NavBackStackEntry's ViewModels until it is added to the NavController's back stack (i.e., the Lifecycle of the NavBackStackEntry reaches the CREATED state).
        at androidx.navigation.NavBackStackEntry.getViewModelStore(NavBackStackEntry.kt:180)
        at androidx.lifecycle.ViewModelProvider.<init>(ViewModelProvider.java:114)
        at androidx.lifecycle.viewmodel.compose.ViewModelKt.get(ViewModel.kt:80)
        at androidx.lifecycle.viewmodel.compose.ViewModelKt.viewModel(ViewModel.kt:72)

I observed that my crashing composable is recomposed after navController.popBackstack(), which ultimately leads to the crash. Is there a reason for the additional recompositions?

Comments

jb...@google.com <jb...@google.com> #2Nov 16, 2021 03:58PM

Project: platform/frameworks/support
Branch: androidx-master-dev

commit c60f33e229e31ab328ef6b59dab63b264954831c
Author: Alexandre Elias <aelias@google.com>
Date: Fri Jul 10 16:23:09 2020

Semantics no-op cleanups

Partly in response to lmr's broad code review, I did a pass of
superficial API/implementation cleanup. The main changes are:

- I changed each Boolean SemanticsProperty where false is equivalent to
not being present to take "Unit" instead. This is conceptually
clearer: it avoids questions like "can I cancel out a semantics from a
merged child by setting it to false?" Because "property = Unit" looks
weird, I also changed the style of these to "property()".

- I moved the Semantics id generator closer to where it's used, in
SemanticsModifierCore. I made it internal and an AtomicInt.
(Note that integer ids are heavily used in the Android
AccessibilityNodeInfo APIs so I can't simply remove them entirely.)

- I deleted dead code. Some examples include SemanticsHintOverrides,
a public API not connected to anything, and SemanticsPropertyKey
merge() open method which is never called. (In both cases I have
a different plan in mind for accessibility.)

Fixes: 145951226
Fixes: 145955412
Test: existing tests
Relnote: "Single-value semantics properties now use a calling style.
For example, 'semantics { hidden = true }' is now written as:
'semantics { hidden() }'."

Change-Id: Ic1afd12ea22c926babc9662f1804d80b33aa0cfc

M ui/integration-tests/benchmark/src/androidTest/java/androidx/ui/benchmark/test/LayoutNodeModifierBenchmark.kt
M ui/ui-core/api/0.1.0-dev15.txt
M ui/ui-core/api/current.txt
M ui/ui-core/api/public_plus_experimental_0.1.0-dev15.txt
M ui/ui-core/api/public_plus_experimental_current.txt
M ui/ui-core/api/restricted_0.1.0-dev15.txt
M ui/ui-core/api/restricted_current.txt
M ui/ui-core/src/androidAndroidTest/kotlin/androidx/ui/graphics/vector/VectorTest.kt
M ui/ui-core/src/androidAndroidTest/kotlin/androidx/ui/semantics/SemanticsTests.kt
M ui/ui-core/src/androidMain/kotlin/androidx/ui/core/AndroidActuals.kt
M ui/ui-core/src/androidMain/kotlin/androidx/ui/core/AndroidComposeView.kt
M ui/ui-core/src/androidMain/kotlin/androidx/ui/core/AndroidComposeViewAccessibilityDelegateCompat.kt
M ui/ui-core/src/androidMain/kotlin/androidx/ui/core/AndroidPopup.kt
M ui/ui-core/src/commonMain/kotlin/androidx/ui/core/Expect.kt
M ui/ui-core/src/commonMain/kotlin/androidx/ui/core/semantics/SemanticsConfiguration.kt
D ui/ui-core/src/commonMain/kotlin/androidx/ui/core/semantics/SemanticsHintOverrides.kt
M ui/ui-core/src/commonMain/kotlin/androidx/ui/core/semantics/SemanticsModifier.kt
M ui/ui-core/src/commonMain/kotlin/androidx/ui/core/semantics/SemanticsNode.kt
M ui/ui-core/src/commonMain/kotlin/androidx/ui/core/semantics/SemanticsOwner.kt
M ui/ui-core/src/commonMain/kotlin/androidx/ui/core/semantics/SemanticsWrapper.kt
M ui/ui-core/src/commonMain/kotlin/androidx/ui/semantics/SemanticsProperties.kt
M ui/ui-foundation/api/0.1.0-dev15.txt
M ui/ui-foundation/api/current.txt
M ui/ui-foundation/api/public_plus_experimental_0.1.0-dev15.txt
M ui/ui-foundation/api/public_plus_experimental_current.txt
M ui/ui-foundation/api/restricted_0.1.0-dev15.txt
M ui/ui-foundation/api/restricted_current.txt
M ui/ui-foundation/src/main/java/androidx/ui/foundation/Clickable.kt
M ui/ui-foundation/src/main/java/androidx/ui/foundation/Dialog.kt
M ui/ui-foundation/src/main/java/androidx/ui/foundation/Scroller.kt
M ui/ui-foundation/src/main/java/androidx/ui/foundation/selection/Selectable.kt
M ui/ui-foundation/src/main/java/androidx/ui/foundation/selection/Toggleable.kt
M ui/ui-foundation/src/main/java/androidx/ui/foundation/semantics/FoundationSemanticsProperties.kt
M ui/ui-material/src/androidTest/java/androidx/ui/material/ButtonTest.kt
M ui/ui-material/src/androidTest/java/androidx/ui/material/CardTest.kt
M ui/ui-material/src/androidTest/java/androidx/ui/material/CheckboxScreenshotTest.kt
M ui/ui-material/src/androidTest/java/androidx/ui/material/RadioButtonScreenshotTest.kt
M ui/ui-material/src/androidTest/java/androidx/ui/material/ScaffoldTest.kt
M ui/ui-material/src/androidTest/java/androidx/ui/material/SnackbarTest.kt
M ui/ui-material/src/androidTest/java/androidx/ui/material/SurfaceTest.kt
M ui/ui-material/src/androidTest/java/androidx/ui/material/ripple/RippleIndicationTest.kt
M ui/ui-material/src/androidTest/java/androidx/ui/material/textfield/TextFieldScreenshotTest.kt
M ui/ui-material/src/main/java/androidx/ui/material/AppBar.kt
M ui/ui-material/src/main/java/androidx/ui/material/TextFieldImpl.kt
M ui/ui-test/src/androidTest/java/androidx/ui/test/AssertsTest.kt
M ui/ui-test/src/androidTest/java/androidx/ui/test/CallSemanticsActionTest.kt
M ui/ui-test/src/androidTest/java/androidx/ui/test/ErrorMessagesTest.kt
M ui/ui-test/src/androidTest/java/androidx/ui/test/FindersTest.kt
M ui/ui-test/src/androidTest/java/androidx/ui/test/PrintToStringTest.kt
M ui/ui-test/src/androidTest/java/androidx/ui/test/ScrollToTest.kt
M ui/ui-test/src/androidTest/java/androidx/ui/test/TextActionsTest.kt
M ui/ui-test/src/main/java/androidx/ui/test/Actions.kt
M ui/ui-test/src/main/java/androidx/ui/test/Filters.kt
M ui/ui-text/api/0.1.0-dev15.txt
M ui/ui-text/api/current.txt
M ui/ui-text/api/public_plus_experimental_0.1.0-dev15.txt
M ui/ui-text/api/public_plus_experimental_current.txt
M ui/ui-text/api/restricted_0.1.0-dev15.txt
M ui/ui-text/api/restricted_current.txt
M ui/ui-text/src/commonMain/kotlin/androidx/ui/text/CoreTextField.kt
M ui/ui-text/src/commonMain/kotlin/androidx/ui/text/TextSemanticsProperties.kt

https://android-review.googlesource.com/1360099

ja...@deepl.com <ja...@deepl.com> #3Nov 18, 2021 10:13AM

I've added a sample project to reproduce the Bug: https://github.com/jannisveerkamp/composebugreporter

All the important code is within the MainScreen Composable/file.

I've noticed the reason to make the app crash is that I emit data to my ViewModel before closing the Dialog. However this works when using composable() instead of dialog()

il...@google.com <il...@google.com> Nov 18, 2021 04:26PM

Assigned to jb...@google.com.

ap...@google.com <ap...@google.com> #4Nov 18, 2021 10:53PM

Project: platform/frameworks/support
Branch: androidx-main

commit 472706e6b170ec44143382f673c8022b944ae731
Author: Jeremy Woods <jbwoods@google.com>
Date: Thu Nov 18 12:25:57 2021

Keep dialog back stack entries until the dialog is disposed

When a Dialog is dismissed the content within is recomposed again before
the dialog is disposed. This causes an issue in Navigation where the
dialog content gets a DESTROYED back stack entry.

To get around this we can pop dialogs with transitions and wait until we
get an onDispose callback to move the back stack entry state.

RelNote: "Fixed an issue where attempting to retrieve a viewModel from
a dialogs `NavBackStackEntry` would fail when the dialog was dismissed."
Test: NavHostTest
Bug: 206465487

Change-Id: I6b96d1ce4bcd703340c1d20968d2416c56b9fe46

M navigation/navigation-compose/src/main/java/androidx/navigation/compose/DialogHost.kt
M navigation/navigation-compose/src/androidTest/java/androidx/navigation/compose/NavHostTest.kt
M navigation/navigation-compose/src/main/java/androidx/navigation/compose/DialogNavigator.kt

https://android-review.googlesource.com/1896853

jb...@google.com <jb...@google.com> #5Nov 18, 2021 10:55PM

Marked as fixed.

This has been fixed internally and will be available in the Navigation 2.4.0-rc01 release.

The fix is actually a work around for a larger issue for Dialogs in Compose which will be tracked here.

ja...@deepl.com <ja...@deepl.com> #6Nov 19, 2021 08:08AM

Wonderful news - thank you for the fast replies!

Issue 206465487