IssueTracker

since these are in public API (:/) we need to do this in 1.2

Opening diff shortly

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

commit d576cbdc911cba16638a44fd8223391a90a07ef7
Author: Mike Nakhimovich <digitalbuddha@users.noreply.github.com>
Date:   Tue Aug 11 09:30:34 2020

    [GH] Hide deprecated internal API.
   
    ## Proposed Changes
   
    * `RoomDatabase.java` has protected `mCallbacks` field which is leaking in the API docs, we should @Hide it.
   
    ## Testing
   
    Test: Ran unit tests locally
   
    ## Issues Fixed
   
    Fixes: 76109329
   
    This is an imported pull request from https://github.com/androidx/androidx/pull/61.
   
    Resolves #61
    Github-Pr-Head-Sha: 6440daa3a63752c7f9d5ba2a390248cd85bc634f
    GitOrigin-RevId: fe92d8466a59b44b218b6ca3cbd57dcda17992f7
   
    Change-Id: Id599cdf5b02b32bdae0166266fb7da967598fe92

A       room/runtime/api/current.ignore
M       room/runtime/api/current.txt
M       room/runtime/api/public_plus_experimental_current.txt
M       room/runtime/api/restricted_current.txt
M       room/runtime/src/main/java/androidx/room/RoomDatabase.java

https://android-review.googlesource.com/1396827

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

commit ce0a07e52f9bbc60ff0983101da22d782ddff391
Author: Jeremy Woods <jbwoods@google.com>
Date:   Tue Aug 10 17:42:26 2021

    Ensure we keep track of all transitioning entries
   
    We currently keep up with all transitioning entries in a set, which
    means we can't keep up with multiple entries that are considered "equal"
    but actually are different objects.
   
    This currently breaks navigate with popUpTo and transitions since we
    will pop first, causing us to consider the old entry as transitioning,
    then when we navigate we attempt to add the new entry as transitioning,
    but since it is "equal" to the old one, the set just ignores the add.
   
    We need to instead make transitionsInProgress a List, meaning we can
    have multiple entries that "equal" each other. This also means we need
    to be sure to clear all the "equal" entries from the list whenever one
    of them is complete.
   
    Relnote: "Re-selecting the same tab when using navigation compose with
    multiple back stacks will no longer result in a blank screen."
   
    Test: added testSameEntry
    Bug: 194925622
   
    Change-Id: I860dc9f2cc2516924c03dba491a37aa8ace99bb3

M       navigation/navigation-common/api/current.txt
M       navigation/navigation-common/api/public_plus_experimental_current.txt
M       navigation/navigation-common/api/restricted_current.txt
M       navigation/navigation-common/src/main/java/androidx/navigation/NavigatorState.kt
M       navigation/navigation-testing/src/androidTest/java/androidx/navigation/testing/TestNavigatorStateTest.kt
M       navigation/navigation-testing/src/main/java/androidx/navigation/testing/TestNavigatorState.kt

https://android-review.googlesource.com/1792930

This is really weird but I believe this issue resurfaced in 2.7.1. I was using 2.5.3 and it was working just fine but today i updated the dependency and this started happening.

Same for me. I was using 2.7.1. When I selected the arrow to navigate back twice quickly, the app would go back one screen, then the screen would go completely blank. When I reverted to 2.5.3, that issue went away.

Same for me. I was using 2.7.2 and, oh man, when I encountered this issue I didn't even know where to start debugging. Thank god it worked just fine when I downgraded to 2.5.3.

same here, just updated from 2.5.3 to 2.7.3 and screen is blank when navigating for second time on same screen

To reproduce this issue, I attached a basic navigation project that consists of screens with buttons that go from one Screen to another.

Additionally, I attached two videos. One using Navigation 2.6.0 shows it is working fine, while the other video using Navigation 2.7.1 shows the strange behavior of a blank flash.

I tested all 2.7.x versions and the 2.8.0 alpha, and it's still happening.

Additionally, in some cases, the transition of the screens is that it enters from the upper right corner to the lower left. This behavior is bizarre and erratic since there is no defined animation, and it happens randomly on the screen. Only when many buttons on the screens are pressed quickly.

Feel free to tag me if there is any advance :(. (I am new here, IDK how this works)

#15 you should report this in a new ticket

Here is a solution that works for me. The blank screen seems to happen if there's no screen in the previous history to navigate to when a user double-clicks the back arrow too quickly.

if (navController.previousBackStackEntry != null) {
                        navController.popBackStack()
                    }

And here is my solution for bottom navigation, always check if the current route is not equal to the route being navigated to:

onClick = {
                    if (selectedItemIndex != index) {
                        localNavController.navigate(
                            route = item.route,
                            builder = {
                                launchSingleTop = true
                                restoreState = true
                                popUpTo(localNavController.graph.startDestinationId) {
                                    saveState = true
                                }
                            }
                        )
                    }
                }