Switches the status bar and navigation bar icons between light and dark, based on the content behind the bars.

EdgeChameleon is a Compose Multiplatform library: add it to commonMain and call Modifier.edgeChameleon() from shared UI code, without expect/actual. It is only implemented on Android, because the other targets don't need it. There the modifier only draws its content, so the same code compiles and runs everywhere. See Platforms.

1. Add the dependency

In a Compose Multiplatform Gradle module (build.gradle.kts):

repositories {
    mavenCentral()
}

kotlin {
    sourceSets {
        commonMain.dependencies {
            implementation("dev.schattauer.edgechameleon:edgechameleon:<version>")
        }
    }
}

In an Android Gradle module (build.gradle.kts):

repositories {
    mavenCentral()
}

dependencies {
    implementation("dev.schattauer.edgechameleon:edgechameleon:<version>")
}

2. Add the modifier to the root of your app content

import dev.schattauer.edgechameleon.edgeChameleon

@Composable
fun App() {
    MyApp(Modifier.fillMaxSize().edgeChameleon())
}

3. Draw edge-to-edge on Android

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        enableEdgeToEdge()
        super.onCreate(savedInstanceState)
        setContent { App() }
    }
}

The icons now follow your content.

Requirements: Android minSdk 23, with sampling from Android 9 (API 28); built with Compose Multiplatform 1.12; the app draws edge-to-edge.

EdgeChameleon is only implemented on Android. The other targets are part of the library so that shared code can use the modifier, and there it only draws its content; the options have no effect.

Taken from the sample app with its debug panel on, which shows the 16 sampled cells of each bar and the chosen icons.

Light content	Dark content	Scrolling	Mixed content
Dark icons	Light icons	Follows what is behind each bar: light icons over a dark band, dark icons over a white one	No icon colour fits the whole bar, so an icon over a different colour can lose contrast

val state = remember { EdgeChameleonState() }

Modifier.edgeChameleon(
    enabled = true,                 // false restores the original icons and stops sampling
    forcedIcons = BarIcons.Light,   // uses these icons and stops sampling
    statusBar = true,               // whether the status bar is handled
    navigationBar = true,           // whether the navigation bar is handled
    state = state,                  // state.statusBarIcons and state.navigationBarIcons hold the current result
)

EdgeChameleonTuning sets the sampling rate, cell count, contrast threshold, hysteresis and zone weights. It is marked @ExperimentalEdgeChameleonApi.

• The content is sampled after it changes, at most 10 times per second, and not at all on a static screen.
• Each bar is reduced to 16 cells, and the cells vote for the icon colour with the better contrast. In the status bar, the outer quarters, where the clock and the system icons sit, count three times. In the navigation bar, every cell counts the same, so the whole width of the bar decides.
• Only Compose content inside the modifier is sampled.
• Sampling pauses while another window, such as a Dialog, has the focus, and the icons keep their tint until then.
• A full-screen Dialog has its own bars: add the modifier to the content of the dialog as well. It has no effect in a dialog that does not reach the bars.
• With gesture navigation, the navigation bar is not handled.
• While active, the navigation bar contrast scrim is turned off. It is restored when the modifier is disabled or removed.
• Disabling or removing the modifier restores the icons the app had before the library first changed them. Changes the app makes to the icons while the modifier is active are replaced.

sample/ holds an Android app with a colour screen, scrolling bands and mixed backgrounds. Its debug toggle shows the sampled cells and the current result.

./gradlew :sample:androidApp:installDebug

• CHANGELOG.md: what changed in each version
• CONTRIBUTING.md: development setup, tests, formatting and pull requests
• SECURITY.md: how to report a vulnerability
• RELEASE.md: how a release is made

Apache License 2.0