In the previous code , currentTopLevelDestination would be momentaril…

[mahmed1987]

Issue
currentTopLevelDestination is null momentarily , causing the TopAppBar to flicker while navigating the top level destinations.
In short the problem lies here

val currentTopLevelDestination: TopLevelDestination?
        @Composable get() {
            return TopLevelDestination.entries.firstOrNull { topLevelDestination ->
                Log.d("currentDestination","$currentDestination")
                currentDestination?.hasRoute(route = topLevelDestination.route) ?: false
            }
        }

The log statement above would confirm that while switching between the top level composables , the currentDestination is obtained as null at times , until it is not .

I dont have the exact reasoning as to why that is. My hypothesis is that since there is no "gate" between the currentDestination composable and the currentTopLevelDestination , currentTopLevelDestination reacts to everything that occurs to currentDestination and perhaps currentDestination goes through a null while going from one destination to another.

Solution

I just gated the currentTopLevelDestination with a remember .

Before
After

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