"Configurations must be unique" error occurring in production

[pavel163]

I have a root component on our screen which includes four configurations: A, B, C, where each configuration corresponds to a different screen. According to the logic, configurations B and C can only be added to the stack with A. However, I encounter production cases where the stack forms as A, B, C, B, which contradicts the designed behavior, as navigating to any screen should first require returning to a state where only A is in the stack.

Multiple root components are showing this issue

[arkivanov]

Sorry but I don't understand the issue. Can you ask a question or describe in more details?

[pavel163]

I have a component similar to DefaultRootComponent, and it's organized in such a way that from one screen you can move to others (in the example these are Tabs). Over the last 90 days, there have been errors when a user navigated the following path: A (Tabs) -> B (DynamicFeatures) -> A (Tabs) -> C (CustomNavigation) -> A (Tabs) -> B (DynamicFeatures). For some reason, when these users returned to A (Tabs), the backstack was not cleared (the pop method was used for returning), and I receive the error java.lang.IllegalStateException - Configurations must be unique: [A, B, C, B].

[arkivanov]

It's hard to tell without any code or reproducer. Make sure you are using appropriate navigation functions. Duplicated configurations are not allowed. A possible issue is when the user double-clicks on a button or similar. Consider using pushNew for navigation.

[leffsu]

Encountered it too on the latest version on the screen with tabs.

java.lang.IllegalStateException: Configurations must be unique: [Landing, Main(mainMenuId=HOME), Tasks, Home, Tasks]. when executing pushNew(Tasks).

The problem with pushNew is that it only check the last item. The workaround in my case is

    inline fun <C : Any> StackNavigator<C>.safePushNew(
        configuration: C,
        crossinline onComplete: (isSuccess: Boolean) -> Unit = {},
    ) {
        navigate(
            transformer = { stack ->
                stack.filter { it != configuration  } + configuration
            },
            onComplete = { newStack, oldStack -> onComplete(newStack.size > oldStack.size) },
        )
    }

What I mean:
we have tabs 1,2,3
we go to tab 1 - config is [1]
we go to tab 2 - config is [1,2]
we go to tab 3 - config is [1,2,3]

Scenario A (happy):
we click to go to tab 3 - config is [1,2,3], nothing happens

Scenario B (reproduced):
we go to tab X (any tab except for 3) - config is [1,2,3,X] now
because pushNew only check for the .last() item in the stack
crash if X is 1 or 2

[arkivanov]

Encountered it too on the latest version on the screen with tabs.

java.lang.IllegalStateException: Configurations must be unique: [Landing, Main(mainMenuId=HOME), Tasks, Home, Tasks]. when executing pushNew(Tasks).

The problem with pushNew is that it only check the last item. The workaround in my case is

    inline fun <C : Any> StackNavigator<C>.safePushNew(
        configuration: C,
        crossinline onComplete: (isSuccess: Boolean) -> Unit = {},
    ) {
        navigate(
            transformer = { stack ->
                stack.filter { it != configuration  } + configuration
            },
            onComplete = { newStack, oldStack -> onComplete(newStack.size > oldStack.size) },
        )
    }

What I mean: we have tabs 1,2,3 we go to tab 1 - config is [1] we go to tab 2 - config is [1,2] we go to tab 3 - config is [1,2,3]

Scenario A (happy): we go to tab 2 - config is [1,2] now we go to tab 1 - config is [1] now

Scenario B (reproduced): we go to tab 1 - config is [1,2,3,1] now because pushNew only check for the .last() item in the stack crash

It looks like you actually need pushToFront.

[leffsu]

Thank you kindly!

@pavel163 please check it out

[leffsu]

On the second thought pushToFront does not allow us to navigate back to the previous tab by clicking "Back" on the navigation bar. Gotta think about it

[arkivanov]

On the second thought pushToFront does not allow us to navigate back to the previous tab by clicking "Back" on the navigation bar. Gotta think about it

I think pushToFront is equivalent to the workaround you provided earlier.