Adds ambient snippet in Compose (#974)

* Adds ambient snippet in Compose

* Apply Spotless

* Restores AlwaysOnActivity

* Apply suggestions from code review

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

* Apply Spotless

* Fixes compilation error introduced by Gemini assist

* Restore deprecated snippets for now

* Restore deprecated snippets for now

* Apply Spotless

---------

Co-authored-by: garanj <25058277+garanj@users.noreply.github.com>
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

Author: garanj

wear/src/main/java/com/example/wear/snippets/alwayson/AlwaysOnActivity.kt

@@ -83,7 +83,7 @@ class AlwaysOnActivity : ComponentActivity() {
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
             when {
                 ContextCompat.checkSelfPermission(this, Manifest.permission.POST_NOTIFICATIONS) ==
-                    PackageManager.PERMISSION_GRANTED -> {
+                        PackageManager.PERMISSION_GRANTED -> {
                     Log.d(TAG, "POST_NOTIFICATIONS permission already granted")
                 }
                 shouldShowRequestPermissionRationale(Manifest.permission.POST_NOTIFICATIONS) -> {
@@ -186,7 +186,7 @@ fun WearApp() {
                                 if (runningService != null) {
                                     Log.d(TAG, "Stopping ${runningService?.simpleName}")
                                     context.stopService(Intent(context, runningService))
-                                 }
+                                }
                                 Log.d(TAG, "Starting ${serviceClass.simpleName}")
                                 val intent = Intent(context, serviceClass)
                                 context.startForegroundService(intent)
@@ -208,4 +208,4 @@ fun WearApp() {
             }
         }
     }
-}
+}

wear/src/main/java/com/example/wear/snippets/alwayson/LocalAmbientModeManager.kt

@@ -0,0 +1,73 @@
+/*
+ * Copyright 2026 The Android Open Source Project
+ *
+ * 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
+ *
+ *     https://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.
+ */
+
+package com.example.wear.snippets.alwayson
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.wear.compose.foundation.AmbientMode
+import androidx.wear.compose.foundation.AmbientTickEffect
+import androidx.wear.compose.foundation.LocalAmbientModeManager
+import androidx.wear.compose.foundation.rememberAmbientModeManager
+import androidx.wear.compose.material3.Text
+
+@Composable
+fun AmbientModeBasicSample() {
+    // [START android_wear_ongoing_activity_ambient_compose]
+    // In a production application, the AmbientModeManager should be instantiated and provided at
+    // the highest level of the Compose hierarchy (typically in the host Activity's setContent
+    // block) using a CompositionLocalProvider. This ensures proper lifecycle management and
+    // broad accessibility.
+
+    // For this self-contained demo, AmbientModeManager is created and provided locally:
+    val activityAmbientModeManager = rememberAmbientModeManager()
+    CompositionLocalProvider(LocalAmbientModeManager provides activityAmbientModeManager) {
+        val ambientModeManager = LocalAmbientModeManager.current
+        val ambientMode = ambientModeManager?.currentAmbientMode
+
+        if (ambientModeManager != null) {
+            ambientModeManager.AmbientTickEffect {
+                // While device is in ambient mode, update properties every minute or so
+                // ...
+            }
+        }
+
+        // [START_EXCLUDE]
+        Column(
+            verticalArrangement = Arrangement.Center,
+            horizontalAlignment = Alignment.CenterHorizontally,
+            modifier = Modifier.fillMaxSize(),
+        ) {
+            // [END_EXCLUDE]
+            val ambientModeName =
+                when (ambientMode) {
+                    is AmbientMode.Interactive -> "Interactive"
+                    is AmbientMode.Ambient -> "Ambient"
+                    else -> "Unknown"
+                }
+
+            Text(text = "$ambientModeName Mode")
+            // [START_EXCLUDE]
+        }
+        // [END_EXCLUDE]
+    }
+    // [END android_wear_ongoing_activity_ambient_compose]
+}