The recommended substitute for clearTask of popUpTo with popUpToInclusive only works from start destination actions [116831650]

Fixed

Bug

Status Update

No update yet.

Description

[Deleted User]

created issue #1

Sep 28, 2018 10:32AM

I was previously using clearTask in my navigation actions to make sure that the user could not navigate back to the previous destination (useful for splash screens and login screens). After it was deprecated I decided to try the recommended approach of instead setting popUpTo pointing to the root of the graph together with setting popUpToInclusive="true", but this didn't have the effect I wanted.

This approach only seem to work on actions originating from the graph's start destination, and fails on actions between any other destinations. I created a sample project which reproduces the issue:

https://github.com/hsson/android-navigation-component-alpha06-bug

Here is the project's README detailing the issue:

# Bug in Android Navigation Component (alpha06)
(Note: I have only verified this in alpha06, I don't know if it exists in
previous versions)

## The problem
Basically the problem is that the NavOption "clearTask" was removed in
alpha02, and the recommended substitute was to use app:popUpTo pointing to
the root of the graph/the graph ID, together with app:popUpToInclusive="true".
However, this method does not work. It only seems to work for actions
going from the graph's start destination. If we have the following graph:

x y
A ---> B ---> C

Where A, B, and C are fragments, A is the start destination of the grapg,
and x, y are actions going from A to B and B to C respectively. Let's say
the graph's ID is "@+id/graph"

Then, if both actions x and y have
app:popUpTo="@+id/graph"
app:popUpToInclusive="true"

Then when navigating from A to B through x, and then hitting the back button
will exit the app (as expected). But if navigating from A to B to C through
x and y, and then hitting the back button we will navigate back to B — this
is not what was expected. The expected behavior with this graph is to always
exit the app when clicking the back button

## Environment
This was verified using:
Android Studio 3.2 RC 3
Build #AI-181.5540.7.32.4987877, built on August 31, 2018
JRE: 1.8.0_152-release-1136-b06 x86_64
JVM: OpenJDK 64-Bit Server VM by JetBrains s.r.o
macOS 10.13.6

Comments

[Deleted User] <[Deleted User]> #2Oct 1, 2018 08:14AM

Is there any updates? This is a big problem!

il...@google.com <il...@google.com> Oct 1, 2018 10:56PM

Assigned to il...@google.com.

[Deleted User] <[Deleted User]> #3Oct 10, 2018 09:20AM

Hi there - could you provide more context on the issue & a sample project to reproduce? Database locked exceptions are quite difficult to pinpoint without a repro project. Thanks!

il...@google.com <il...@google.com> #4Oct 18, 2018 06:05PM

Hi. It is reproduceable on some users by using this code:

suspend fun <R> MyDatabase.workaroundWithTransaction(block: suspend TransactionScope<R>.() -> R) {
    useWriterConnection {
        it.immediateTransaction(block)
    }

    // TODO: Temporally fix https://issuetracker.google.com/issues/340606803#comment2
    // Manually triggers invalidation
    invalidationTracker.refreshAsync()
}

[Deleted User] <[Deleted User]> #5Oct 19, 2018 11:44AM

Maybe it is about this? https://android-review.googlesource.com/c/platform/frameworks/support/+/3114928

I am not sure.

mi...@gmail.com <mi...@gmail.com> #6Oct 19, 2018 12:22PM

Hi. Please merge the pull request. This is big problem!

[Deleted User] <[Deleted User]> #7Oct 19, 2018 12:24PM

Hi. Is there any updates on this problem?

il...@google.com <il...@google.com> #8Oct 19, 2018 03:36PM

Hi, I updated my version to alpha12 but still have these crashes. Please release a fix asap.

mi...@gmail.com <mi...@gmail.com> #9Oct 19, 2018 03:50PM

Will there be fixes released this Wednesday?

il...@google.com <il...@google.com> #10Oct 19, 2018 04:13PM

Hey, there is no release on Wednesday (holiday in the USA)

We haven't found the root cause of this exception, it happens when SQLite can't commit the transaction because some other connection has a lock, we need more information, a sample project that reproduces the issue preferably, or more details on how the database is being used (is it from multiple process? is there heavy concurrency?).

You can also increase the time SQLite will wait before it error with 'database locked' by executing PRAGMA busy_timeout = <time in ms>, the current default is 3000

mi...@gmail.com <mi...@gmail.com> #11Oct 19, 2018 04:16PM

Thank you for you response.

Isn't these pull request addressed this issue? 1.1 https://android-review.googlesource.com/c/platform/frameworks/support/+/3408679 1.2 https://android-review.googlesource.com/c/platform/frameworks/support/+/3114928
According to RoomDB documentation about withTransaction: "Room will only perform at most one transaction at a time, additional transactions are queued and executed on a first come, first serve order." So the transaction should just wait for other transaction to complete and not throw exception instead. Isn't it?

dc...@gmail.com <dc...@gmail.com> #12Oct 23, 2018 05:19PM

I tried to use this code and still getting the same error from users. (deferredTransaction instead of immediateTransaction)

private val dbMutex = Mutex()

suspend fun <R> MyDatabse.workaroundWithTransaction(block: suspend TransactionScope<R>.() -> R) {
    dbMutex.withLock {
        useWriterConnection {
            it.deferredTransaction(block)
        }

        // TODO: Fix https://issuetracker.google.com/issues/340606803#comment2
        // Manually triggers invalidation
        invalidationTracker.refreshAsync()
    }
}

da...@gmail.com <da...@gmail.com> #13Oct 26, 2018 10:58PM

Moreover now I am also think that @Update function caused particularly this crash. I will monitor the situation to this if this 1 crash or it will be more with the same reason.

il...@google.com <il...@google.com> #14Nov 30, 2018 11:21PM

Marked as fixed.

After checking I can confirm that this crash happens as many as before.