theming + material you

modules/astra-system-colors/android/build.gradle

@@ -0,0 +1,18 @@
+plugins {
+  id 'com.android.library'
+  id 'expo-module-gradle-plugin'
+}
+
+group = 'expo.modules.astrasystemcolors'
+version = '0.1.0'
+
+android {
+  namespace "expo.modules.astrasystemcolors"
+  defaultConfig {
+    versionCode 1
+    versionName "0.1.0"
+  }
+  lintOptions {
+    abortOnError false
+  }
+}

modules/astra-system-colors/android/src/main/java/expo/modules/astrasystemcolors/AstraSystemColorsModule.kt

@@ -0,0 +1,110 @@
+package expo.modules.astrasystemcolors
+
+import android.os.Build
+import expo.modules.kotlin.modules.Module
+import expo.modules.kotlin.modules.ModuleDefinition
+
+/**
+ * Exposes Android 12+ monet system palettes (wallpaper-derived) to JS.
+ * Each ramp is 13 hex strings ordered by tone [0, 10, 50, 100..1000].
+ * Sync Functions on purpose: resource reads are microseconds, and it avoids
+ * the zero-arg Coroutine {} overload ambiguity in expo-modules-core.
+ */
+class AstraSystemColorsModule : Module() {
+  override fun definition() = ModuleDefinition {
+    Name("AstraSystemColors")
+
+    Function("isAvailable") { Build.VERSION.SDK_INT >= 31 }
+
+    Function("getSystemPalette") {
+      if (Build.VERSION.SDK_INT < 31) return@Function null
+      val context = appContext.reactContext ?: return@Function null
+      fun ramp(ids: IntArray) = ids.map { String.format("#%06x", context.getColor(it) and 0xFFFFFF) }
+      mapOf(
+        "accent1" to ramp(ACCENT1),
+        "accent2" to ramp(ACCENT2),
+        "accent3" to ramp(ACCENT3),
+        "neutral1" to ramp(NEUTRAL1),
+        "neutral2" to ramp(NEUTRAL2),
+      )
+    }
+  }
+
+  companion object {
+    private val ACCENT1 = intArrayOf(
+      android.R.color.system_accent1_0,
+      android.R.color.system_accent1_10,
+      android.R.color.system_accent1_50,
+      android.R.color.system_accent1_100,
+      android.R.color.system_accent1_200,
+      android.R.color.system_accent1_300,
+      android.R.color.system_accent1_400,
+      android.R.color.system_accent1_500,
+      android.R.color.system_accent1_600,
+      android.R.color.system_accent1_700,
+      android.R.color.system_accent1_800,
+      android.R.color.system_accent1_900,
+      android.R.color.system_accent1_1000,
+    )
+    private val ACCENT2 = intArrayOf(
+      android.R.color.system_accent2_0,
+      android.R.color.system_accent2_10,
+      android.R.color.system_accent2_50,
+      android.R.color.system_accent2_100,
+      android.R.color.system_accent2_200,
+      android.R.color.system_accent2_300,
+      android.R.color.system_accent2_400,
+      android.R.color.system_accent2_500,
+      android.R.color.system_accent2_600,
+      android.R.color.system_accent2_700,
+      android.R.color.system_accent2_800,
+      android.R.color.system_accent2_900,
+      android.R.color.system_accent2_1000,
+    )
+    private val ACCENT3 = intArrayOf(
+      android.R.color.system_accent3_0,
+      android.R.color.system_accent3_10,
+      android.R.color.system_accent3_50,
+      android.R.color.system_accent3_100,
+      android.R.color.system_accent3_200,
+      android.R.color.system_accent3_300,
+      android.R.color.system_accent3_400,
+      android.R.color.system_accent3_500,
+      android.R.color.system_accent3_600,
+      android.R.color.system_accent3_700,
+      android.R.color.system_accent3_800,
+      android.R.color.system_accent3_900,
+      android.R.color.system_accent3_1000,
+    )
+    private val NEUTRAL1 = intArrayOf(
+      android.R.color.system_neutral1_0,
+      android.R.color.system_neutral1_10,
+      android.R.color.system_neutral1_50,
+      android.R.color.system_neutral1_100,
+      android.R.color.system_neutral1_200,
+      android.R.color.system_neutral1_300,
+      android.R.color.system_neutral1_400,
+      android.R.color.system_neutral1_500,
+      android.R.color.system_neutral1_600,
+      android.R.color.system_neutral1_700,
+      android.R.color.system_neutral1_800,
+      android.R.color.system_neutral1_900,
+      android.R.color.system_neutral1_1000,
+    )
+    private val NEUTRAL2 = intArrayOf(
+      android.R.color.system_neutral2_0,
+      android.R.color.system_neutral2_10,
+      android.R.color.system_neutral2_50,
+      android.R.color.system_neutral2_100,
+      android.R.color.system_neutral2_200,
+      android.R.color.system_neutral2_300,
+      android.R.color.system_neutral2_400,
+      android.R.color.system_neutral2_500,
+      android.R.color.system_neutral2_600,
+      android.R.color.system_neutral2_700,
+      android.R.color.system_neutral2_800,
+      android.R.color.system_neutral2_900,
+      android.R.color.system_neutral2_1000,
+    )
+  }
+}

modules/astra-system-colors/expo-module.config.json

@@ -0,0 +1,6 @@
+{
+  "platforms": ["android"],
+  "android": {
+    "modules": ["expo.modules.astrasystemcolors.AstraSystemColorsModule"]
+  }
+}

modules/astra-system-colors/index.ts

@@ -0,0 +1,28 @@
+import { requireOptionalNativeModule, type NativeModule } from 'expo-modules-core';
+
+/**
+ * Android 12+ monet system palettes (wallpaper-derived). Each ramp is 13 hex
+ * strings ordered by tone [0, 10, 50, 100, 200, ..., 900, 1000] — tone 0 is
+ * white-ish, tone 1000 black-ish.
+ */
+export interface SystemPalette {
+  accent1: string[];
+  accent2: string[];
+  accent3: string[];
+  neutral1: string[];
+  neutral2: string[];
+}
+
+declare class AstraSystemColorsModuleType extends NativeModule {
+  /** True on Android 12+ builds that include the native module. */
+  isAvailable(): boolean;
+  /** Current monet ramps, or null when unavailable. Sync — resource reads are microseconds. */
+  getSystemPalette(): SystemPalette | null;
+}
+
+const native = requireOptionalNativeModule<AstraSystemColorsModuleType>('AstraSystemColors');
+
+export const AstraSystemColors = (native ?? {
+  isAvailable: () => false,
+  getSystemPalette: () => null,
+}) as AstraSystemColorsModuleType;