NavHostFragment crashes when a custom DialogNavigator is used [175979140]

Fixed

Bug

Status Update

No update yet.

Description

ru...@gmail.com

created issue #1

Dec 20, 2020 09:20PM

Component used: Navigation
Version used: 2.3.2

Caused by:
- NavHostFragment looks up a DialogFragmentNavigator in "onAttachFragment" and no null check is done
- A custom Dialog fragment navigator can't extend from DialogFragmentNavigator as it's a final class

Commit that introduced this:

https://android.googlesource.com/platform/frameworks/support/+/2674709cf3f9d2d46c9bcee55ec01eb115143aaa

Can the new API be used instead to fix this issue in the next alpha/beta release?
In alternative, do you suggest other workaround or should we wait and stay in 2.3.1 until this is fixed?

Comments

il...@google.com <il...@google.com> #2Dec 23, 2020 11:57PM

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

ru...@gmail.com <ru...@gmail.com> #3Dec 28, 2020 06:55PM

I use a custom Dialog navigator that doesn't allow 2 dialogs open at the same time. I'll create a sample project in the next few days

ru...@gmail.com <ru...@gmail.com> #4Jan 5, 2021 05:09PM

Sample project here:

https://github.com/rubensousa/CustomNavigatorSample

Crash on 2.3.2:
Caused by: java.lang.ClassCastException: com.navigation.sample.SingleDialogNavigator cannot be cast to androidx.navigation.fragment.DialogFragmentNavigator
at androidx.navigation.fragment.NavHostFragment.onAttachFragment(NavHostFragment.java:293)

Expected behavior: no crash as in 2.3.1

ru...@gmail.com <ru...@gmail.com> #5Feb 8, 2021 11:04PM

Any update on this? This is preventing us from updating to newer releases

il...@google.com <il...@google.com> Apr 6, 2021 07:45PM

Assigned to il...@google.com.

ap...@google.com <ap...@google.com> #6Apr 7, 2021 04:10PM

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

commit ffe68e0a3be1da83217fadd4e40c5abad4f72b82
Author: Ian Lake <ilake@google.com>
Date: Tue Apr 06 12:40:35 2021

Use FragmentOnAttachListener in DialogFragmentNavigator

Rather than having the NavHostFragment
explicitly look for the DialogFragmentNavigator
to forward the fragment attach callback,
have DialogFragmentNavigator use the
Fragment 1.3 FragmentOnAttachListener API
to fully contain that logic within the
DialogFragmentNavigator.

Relnote: "`NavHostFragment` now supports custom
Navigators that use the same `@Navigator.Name(\"dialog\")`
as the default `DialogFragmentNavigator`."
Test: existing tests still pass
BUG: 175979140

Change-Id: Ib1c2cc38e7a621d133be1f4c3692e62913450dda

M navigation/navigation-fragment/api/public_plus_experimental_current.txt
M navigation/navigation-fragment/src/main/java/androidx/navigation/fragment/DialogFragmentNavigator.kt
M navigation/navigation-fragment/src/main/java/androidx/navigation/fragment/NavHostFragment.kt

https://android-review.googlesource.com/1665820

il...@google.com <il...@google.com> #7Apr 7, 2021 05:31PM

Marked as fixed.

In the upcoming Navigation 2.4.0-alpha01, we've updated our Fragment dependency such that we can use the Fragment 1.3.0's API of FragmentOnAttachListener to handle the case where previously the NavHostFragment needed to be involved. Thus, NavHostFragment no longer needs to cast the Navigator returned by the dialog name to DialogNavigator.

As a workaround, your custom Navigator can use any name other than dialog (say, singleDialog) and it'll work just fine if you use that instead of dialog.

ru...@gmail.com <ru...@gmail.com> #8Apr 7, 2021 05:49PM

Thank you for fixing this. Would singleDialog have to be also used in the navigation resources files? I didn't know we could create custom navigation targets with different names outside of dialog, fragment and activity

il...@google.com <il...@google.com> #9Apr 7, 2021 05:54PM

The default DialogFragmentNavigator, FragmentNavigator, and ActivityNavigator use the exact same @Navigator.Name API as is available to every custom Navigator (there's no special casing on the Navigation library side), so yes, it can also be used from XML.