Desktop

Enro runs on Compose Multiplatform for Desktop. main calls installNavigationController once, then opens each window through the returned controller.

Minimal install

fun main() {
    val controller = MyComponent.installNavigationController(Unit)
    controller.openWindow(
        GenericRootWindow(
            windowConfiguration = {
                RootWindow.WindowConfiguration(
                    title = "My App",
                    onCloseRequest = { navigation.close() },
                )
            },
        ) {
            val container = rememberNavigationContainer(
                backstack = backstackOf(Home.asInstance()),
            )
            NavigationDisplay(state = container)
        },
    )

    application {
        EnroApplicationContent(controller)
    }
}

• installNavigationController(Unit) installs the controller for the process and returns the EnroController.
• controller.openWindow(...) registers a window with the controller. The windowConfiguration lambda returns the window’s RootWindow.WindowConfiguration: title, window state, visibility, key event handlers and onCloseRequest. The trailing lambda is the window’s Compose content.
• EnroApplicationContent(controller), called inside Compose Multiplatform’s application { }, renders every window registered with the controller.

The onCloseRequest lambda and the key event lambdas have a RootWindowScope receiver, and RootWindowScope.navigation is the window’s NavigationHandle. onCloseRequest = { navigation.close() } closes the window’s destination, which removes the window. navigation.close() is the default onCloseRequest.

Multi-window apps

Each window is a root navigation destination. controller.openWindow(...) opens a window from outside a destination. navigation.open(...) opens a window destination from another destination.

The desktop main file of the recipes app is an example with a MenuBar, key shortcuts and a complete WindowConfiguration.

A destination in its own window

rootWindowDestination binds a key to a window. navigation.open(key) opens the window. navigation.close() and navigation.complete(value) close the window. A window destination bound to a NavigationKey.WithResult<T> key returns a result with complete.

@NavigationDestination(NoteWindow::class)
val noteWindowDestination = rootWindowDestination<NoteWindow>(
    windowConfiguration = {
        RootWindow.WindowConfiguration(
            title = "New note",
            // The window's close button closes the destination without a result.
            onCloseRequest = { navigation.close() },
        )
    },
) {
    var text by remember { mutableStateOf("") }
    MaterialTheme {
        Surface(modifier = Modifier.fillMaxSize()) {
            Column(
                modifier = Modifier.padding(16.dp),
                verticalArrangement = Arrangement.spacedBy(8.dp),
            ) {
                Text("Note ${navigation.key.number}", style = MaterialTheme.typography.titleLarge)
                TextField(value = text, onValueChange = { text = it })
                // Completing closes the window and delivers the result.
                Button(onClick = { navigation.complete(text) }) { Text("Save") }
                Button(onClick = { navigation.close() }) { Text("Discard") }
            }
        }
    }
}

To open an existing common destination in a window on desktop only, annotate a rootWindowDestination with @NavigationDestination.PlatformOverride(Key::class).

See the Multiple Windows recipe.

What Enro provides on desktop

• Each window hosts its own navigation containers and has its own NavigationHandle.
• Enro does not restore the backstack after a process restart on desktop. An app that requires the backstack after a restart must save and restore the backstack itself.
• The common API: NavigationKey, NavigationKey.WithResult<T>, navigationHandle<T>(), registerForNavigationResult, NavigationDisplay, scene strategies, plugins, decorators.

See also

• Installation — installation on every platform.
• Recipes desktop main — an example with several windows, a MenuBar and key shortcuts.