Reflection Navigation

❯ Description

Just another Jetpack Compose Navigation Library that uses the power of Kotlin Reflection, GSON, and Kotlin extension.

Kotlin Reflection is used to reflect the code at runtime, like knowing the parameter name.

GSON is used to parse Object as String and vise versa.

Kotlin Extension is used provide new function to already existing compose navigation API.

Work like the latest type-safe Jetpack Compose Navigation but without Serializer. Should be fast enough to build because not using KSP and generated code.

❯ Download

Add the dependency below into your module's build.gradle file:

dependencies {
    implementation("io.github.jimlyas:reflection-navigation:0.1.0")
}

R8 / Proguard

The specific rules are already bundled into the JAR which can be interpreted by R8 automatically.

❯ Implementation

Define Route

Make an Object or data class first and we will use it as route for your Screen and just slap the annotation @ReflectiveRoute at the top.

// Screen without any navigation argument
@ReflectiveRoute
object SomeRoute

// Screen with some argument
@ReflectiveRoute
data class OtherRoute(val someData: String, val someClassMaybe: SomeClass)

The annotation doesn't used to generate or parse your code. It is only used to prevent your code to be obfuscated.

As of why any route need to be preserved because the parameter name is used as the argument name, might not work properly with dynamic link if it's obfuscated.

Register to NavGraphBuilder

Use the object or class you make earlier and register it to your NavGraphBuilder using the extension function composeRoute.

NavHost(
    modifier = Modifier.padding(innerPadding),
    navController = controller,
    // Register your start destination like this by calling asRouteName() function
    startDestination = RouteA::class.asRouteName()
) {
    // basic screen
    composeRoute<RouteA> { YourComposeScreen() }

    // with deep link registered
    composeRoute<RouteB>(
        deepLinks = listOf(deeplinkA, deepLinkB)
    ) { YourOtherComposeScreen() }
}

Navigate to destination

To start navigating to other screen, use navigateTo from your NavController by passing the instance the route that associated with intended screen.

// Navigate without any arguments
navController.navigateTo(RouteA)

// Navigate with some arguments
navController.navigateTo(RouteB("someData", 69, false))

Get Argument

There's two ways you can obtain the arguments passed from the navigation, call the function getArg from SavedStateHandler in ViewModel or from NavBackStackEntry when calling composeRoute.

// From ViewModel
@HiltViewModel
class SomeViewModel @Inject constructor(savedStateHandle: SavedStateHandle) : ViewModel() {
    val args = savedStateHandle.getArg<RouteB>()
}

// From composeRoute
composeRoute<RouteB> {
    val args = it.getArg<RouteB>()
    RouteBScreen(args)
}

Which one is better? You do you. The return type will be nullable to prevent crashed if reflection failed to initialize your route instance or if your route class doesn't have primary constructor (which rarely happen I guess).

❯ License

Copyright (c) 2024 Jimly Asshiddiqy

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.