Snippets for /training/wearables/data/data-items (#696)

Author: ithinkihaveacat

wear/src/main/java/com/example/wear/snippets/com/example/wear/snippets/datalayer/DataLayerActivity.kt

@@ -0,0 +1,82 @@
+/*
+ * Copyright 2025 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.com.example.wear.snippets.datalayer
+
+import androidx.activity.ComponentActivity
+import com.google.android.gms.tasks.Task
+import com.google.android.gms.wearable.DataClient
+import com.google.android.gms.wearable.DataEvent
+import com.google.android.gms.wearable.DataEventBuffer
+import com.google.android.gms.wearable.DataItem
+import com.google.android.gms.wearable.DataMapItem
+import com.google.android.gms.wearable.PutDataMapRequest
+import com.google.android.gms.wearable.PutDataRequest
+import com.google.android.gms.wearable.Wearable
+
+class DataLayerActivity : ComponentActivity(), DataClient.OnDataChangedListener {
+    private val dataClient by lazy { Wearable.getDataClient(this) }
+    private val messageClient by lazy { Wearable.getMessageClient(this) }
+    private val capabilityClient by lazy { Wearable.getCapabilityClient(this) }
+
+    private var count = 0
+
+    override fun onResume() {
+        super.onResume()
+        Wearable.getDataClient(this).addListener(this)
+    }
+
+    override fun onPause() {
+        super.onPause()
+        Wearable.getDataClient(this).removeListener(this)
+    }
+
+    // [START android_wear_datalayer_increasecounter]
+    private fun increaseCounter() {
+        val putDataReq: PutDataRequest = PutDataMapRequest.create("/count").run {
+            dataMap.putInt(COUNT_KEY, count++)
+            asPutDataRequest()
+        }
+        val putDataTask: Task<DataItem> = dataClient.putDataItem(putDataReq)
+    }
+    // [END android_wear_datalayer_increasecounter]
+
+    // [START android_wear_datalayer_ondatachangedlistener]
+    override fun onDataChanged(dataEvents: DataEventBuffer) {
+
+        dataEvents.forEach { event ->
+            // DataItem changed
+            if (event.type == DataEvent.TYPE_CHANGED) {
+                event.dataItem.also { item ->
+                    if (item.uri.path?.compareTo("/count") == 0) {
+                        DataMapItem.fromDataItem(item).dataMap.apply {
+                            updateCount(getInt(COUNT_KEY))
+                        }
+                    }
+                }
+            } else if (event.type == DataEvent.TYPE_DELETED) {
+                // DataItem deleted
+            }
+        }
+    }
+    // [END android_wear_datalayer_ondatachangedlistener]
+
+    private fun updateCount(int: Int) {
+    }
+    companion object {
+        private const val COUNT_KEY = "com.example.key.count"
+    }
+}