feat!: update Maps SDK to v20.0.0 and add internal usage attribution

Updates the Maps SDK dependencies and implements internal usage attribution using androidx.startup.

Changes:
- Replaced manual initialization with AttributionIdInitializer using androidx.startup.
- Removed GoogleMapsInitializer and MapsComposeApplication (Breaking Change).
- Updated README.md with attribution opt-out instructions.
- Added installAndLaunch Gradle task for easier demo app testing.
- Fixed ScaleBarTests density calculation.
- Updated minSdk overrides for test dependencies.

Breaking Changes:
- GoogleMapsInitializer and MapsComposeApplication have been removed. Initialization is now handled automatically by androidx.startup.
- minSdk is now 23.

Author: dkhawk

README.md

@@ -497,10 +497,21 @@ The colors of the text, line, and shadow are also all configurable (e.g., based
 
 ## Internal usage attribution ID
 
-This library calls the MapsApiSettings.addInternalUsageAttributionId method, which helps Google
-understand which libraries and samples are helpful to developers and is optional. Instructions for
-opting out of the identifier are provided in
-[reference documentation](maps-compose/src/main/java/com/google/maps/android/compose/internal/GoogleMapsInitializer.kt#L77-L82).
+This library calls the `addInternalUsageAttributionId` method, which helps Google understand which libraries and samples are helpful to developers and is optional. Instructions for opting out of the identifier are provided below.
+
+If you wish to disable this, you can do so by removing the initializer in your `AndroidManifest.xml` using the `tools:node="remove"` attribute:
+
+```xml
+<provider
+    android:name="androidx.startup.InitializationProvider"
+    android:authorities="${applicationId}.androidx-startup"
+    android:exported="false"
+    tools:node="merge">
+    <meta-data
+        android:name="com.google.maps.android.compose.utils.attribution.AttributionIdInitializer"
+        tools:node="remove" />
+</provider>
+```
 
 ## Contributing
 

build.gradle.kts

@@ -35,4 +35,11 @@ allprojects {
     // {x-release-please-start-version}
     version = "7.0.0"
     // {x-release-please-end}
+}
+
+tasks.register<Exec>("installAndLaunch") {
+    description = "Installs and launches the demo app."
+    group = "install"
+    dependsOn(":maps-app:installDebug")
+    commandLine("adb", "shell", "am", "start", "-n", "com.google.maps.android.compose/.MainActivity")
 }

gradle/libs.versions.toml

@@ -1,30 +1,31 @@
 [versions]
-activitycompose = "1.12.1"
-agp = "8.13.1"
+activitycompose = "1.12.2"
+agp = "8.13.2"
 androidCore = "1.7.0"
 androidx-core = "1.17.0"
 androidxtest = "1.7.0"
-compose-bom = "2025.12.00"
+androidx-startup = "1.2.0"
+compose-bom = "2026.01.00"
 dokka = "2.1.0"
 espresso = "3.7.0"
-gradleMavenPublishPlugin = "0.35.0"
+gradleMavenPublishPlugin = "0.36.0"
 jacoco-plugin = "0.2.1"
 junit = "4.13.2"
 junitktx = "1.3.0"
-kotlin = "2.2.21"
+kotlin = "2.3.0"
 kotlinxCoroutines = "1.10.2"
 leakcanaryAndroid = "2.14"
 mapsecrets = "2.0.1"
-mapsktx = "5.2.1"
+mapsktx = "5.2.2"
 material3 = "1.4.0"
 materialIconsExtendedAndroid = "1.7.8"
-mockk = "1.14.6"
-mockkAndroid = "1.14.6"
+mockk = "1.14.7"
+mockkAndroid = "1.14.7"
 org-jacoco-core = "0.8.14"
-screenshot = "0.0.1-alpha12"
+screenshot = "0.0.1-alpha13"
 constraintlayout = "2.2.1"
 material = "1.13.0"
-robolectric = "4.16"
+robolectric = "4.16.1"
 truth = "1.4.5"
 
 [libraries]
@@ -40,6 +41,7 @@ androidx-compose-ui-preview-tooling = { module = "androidx.compose.ui:ui-tooling
 androidx-compose-ui-tooling = { module = "androidx.compose.ui:ui-tooling" }
 androidx-core = { module = "androidx.core:core-ktx", version.ref = "androidx-core" }
 androidx-test-compose-ui = { module = "androidx.compose.ui:ui-test-junit4" }
+androidx-startup-runtime = { module = "androidx.startup:startup-runtime", version.ref = "androidx-startup" }
 androidx-test-core = { module = "androidx.test:core", version.ref = "androidCore" }
 androidx-test-espresso = { module = "androidx.test.espresso:espresso-core", version.ref = "espresso" }
 androidx-test-junit-ktx = { module = "androidx.test.ext:junit-ktx", version.ref = "junitktx" }

maps-app/src/androidTest/AndroidManifest.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools">
+
+    <uses-sdk tools:overrideLibrary="io.mockk.android,io.mockk.proxy.android" />
+</manifest>

maps-app/src/androidTest/java/com/google/maps/android/compose/GoogleMapViewTests.kt

@@ -31,8 +31,6 @@ import com.google.android.gms.maps.model.CameraPosition
 import com.google.android.gms.maps.model.LatLng
 import com.google.common.truth.Truth.assertThat
 import com.google.maps.android.compose.LatLngSubject.Companion.assertThat
-import com.google.maps.android.compose.internal.DefaultGoogleMapsInitializer
-import com.google.maps.android.compose.internal.InitializationState
 import kotlinx.coroutines.runBlocking
 import org.junit.Before
 import org.junit.Rule
@@ -54,13 +52,7 @@ class GoogleMapViewTests {
         val countDownLatch = CountDownLatch(1)
 
         val appContext: Context = InstrumentationRegistry.getInstrumentation().targetContext
-        val googleMapsInitializer = DefaultGoogleMapsInitializer()
 
-        runBlocking {
-            googleMapsInitializer.initialize(appContext)
-        }
-
-        assertThat(googleMapsInitializer.state.value).isEqualTo(InitializationState.SUCCESS)
 
         composeTestRule.setContent {
             GoogleMapView(

maps-app/src/androidTest/java/com/google/maps/android/compose/ScaleBarTests.kt

@@ -16,8 +16,10 @@ package com.google.maps.android.compose
 
 import android.graphics.Point
 import androidx.compose.foundation.layout.Box
+import androidx.compose.ui.platform.LocalDensity
 import androidx.compose.ui.test.junit4.createComposeRule
 import androidx.compose.ui.test.onNodeWithText
+import androidx.compose.ui.unit.Density
 import androidx.compose.ui.unit.dp
 import com.google.android.gms.maps.model.CameraPosition
 import com.google.android.gms.maps.model.LatLng
@@ -44,6 +46,7 @@ class ScaleBarTests {
     val composeTestRule = createComposeRule()
 
     private lateinit var cameraPositionState: CameraPositionState
+    private lateinit var density: Density
 
     private fun initScaleBar(initialZoom: Float, initialPosition: LatLng) {
         check(hasValidApiKey) { "Maps API key not specified" }
@@ -55,6 +58,7 @@ class ScaleBarTests {
         )
 
         composeTestRule.setContent {
+            density = LocalDensity.current
             Box {
                 GoogleMap(
                     cameraPositionState = cameraPositionState,
@@ -87,7 +91,9 @@ class ScaleBarTests {
             val projection = cameraPositionState.projection
             projection?.let { proj ->
                 val widthInDp = 65.dp
-                val widthInPixels = widthInDp.value.toInt()
+                val widthInPixels = with(density) {
+                    widthInDp.toPx().toInt()
+                }
 
                 val upperLeftLatLng = proj.fromScreenLocation(Point(0, 0))
                 val upperRightLatLng = proj.fromScreenLocation(Point(0, widthInPixels))