phantomknight287/Portfolio

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replaced music ai with aerodd41bdaa year ago191 lines · 6.3 KB

1	---
2	title: "Build Wear OS Apps and Connect with Android"
3	summary: "Create Wear OS app and integrate them with Android, covering setup, permissions, and data sync."
4	date: 2025-11-06
5	---
6
7	## Initial Setup
8
9	Start by creating an android app using your preferred framework and open your project in Android Studio (open the `android` folder if using cross-platform frameworks).
10
11	## Phone App Setup
12
13	First, we need to bind a listener so we can listen to messages sent by our watch even when our app is closed/killed. This requires adding permissions and implementing the package. Don't worry about prompting users for permissions - its not needed as it is a [normal](https://developer.android.com/guide/topics/permissions/overview#normal) permission.
14
15	### Adding Dependencies
16
17	Add the following to your app level gradle file (`app/build.gradle`):
18
19	```kotlin
20	implementation("com.google.android.gms:play-services-wearable:19.0.0")
21	```
22
23	Don't forget to press `Sync Now`
24
25	### Permissions Setup
26
27	Add the following code in the `manifest` block of `AndroidManifest.xml`:
28
29	```xml
30	<uses-permission android:name="com.google.android.wearable.permission.BIND_WEARABLE_LISTENER" />
31	```
32
33	### Creating Message Receiver
34
35	Now, we'll write a service that will be `android:exported`. Create a new file `WearMessageReceiver.kt` in the same folder as `MainActivity.kt`:
36
37	```kotlin
38	package com.your.package
39
40	import android.content.Intent
41	import com.google.android.gms.wearable.MessageEvent
42	import com.google.android.gms.wearable.WearableListenerService
43
44	class WearMessageReceiver : WearableListenerService() {
45	override fun onMessageReceived(event: MessageEvent) {
46	when (event.path) {
47	"/open" -> {
48	val intent = packageManager.getLaunchIntentForPackage(packageName)?.apply {
49	addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
50	addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)
51	}
52	startActivity(intent)
53	}
54	}
55	}
56	}
57	```
58
59	The above code listens for the `/open` message and when received, it opens the app.
60
61	### Registering the Service
62
63	We need to tell our phone about this service. Add the following code in the `application` block of `AndroidManifest.xml`:
64
65	```xml
66	<service
67	android:name="[package name].WearMessageReceiver"
68	android:exported="true">
69	<intent-filter>
70	<action android:name="com.google.android.gms.wearable.MESSAGE_RECEIVED" />
71	<category android:name="android.intent.category.DEFAULT" />
72	<data
73	android:host="*"
74	android:pathPattern=".*"
75	android:scheme="wear" />
76	</intent-filter>
77	</service>
78	```
79
80	### Message Sending Function
81
82	This function sends messages from our phone to the watch. Add it to `MainActivity.kt`:
83
84	```kotlin
85	suspend fun sendMessageToWatch(
86	context: Context,
87	path: String,
88	data: ByteArray = ByteArray(0)
89	) {
90	withContext(Dispatchers.IO) {
91	try {
92	val nodes = Tasks.await(Wearable.getNodeClient(context).connectedNodes)
93	// it is recommended to filter out nodes with `isNearby = false`
94	nodes.forEach { node ->
95	Tasks.await(
96	Wearable.getMessageClient(context).sendMessage(
97	node.id,
98	path,
99	data,
100	)
101	)
102	}
103	} catch (e: Exception) {
104	e.printStackTrace()
105	}
106	}
107	}
108	```
109
110	Read more on suspend functions [here](https://kotlinlang.org/docs/composing-suspending-functions.html).
111
112	## Watch App Setup
113
114	Here, you'll need a Wear OS device connected to your phone and connected to your PC via wireless debugging. Don't have a Wear OS device? No problem! Create a new emulator and run it following the setup instructions. Unlike Apple Watch simulator, it will connect to your physical phone or emulator.
115
116	### Creating the Watch Project
117
118	1. Go to `Android Studio > File > New > New Project > Wear OS > Empty Wear App`
119	2. Keep the bundle identifier same as your phone app
120	3. Connect a Wear OS device or create an emulator
121
122	### Adding Permissions
123
124	Just like the phone app, we need to bind a listener and add permissions. Add to the `manifest` block in `AndroidManifest.xml`:
125
126	```xml
127	<uses-permission android:name="com.google.android.wearable.permission.BIND_WEARABLE_LISTENER" />
128	```
129
130	### Creating Message Listener
131
132	Create `MessageListenerService.kt`:
133
134	```kotlin
135	// make sure the name of this class matches the one in AndroidManifest.xml
136	class MessageListenerService : WearableListenerService() {
137	override fun onMessageReceived(event: MessageEvent) {
138	super.onMessageReceived(event)
139	when (event.path) {
140	"/boot" -> {
141	val intent = Intent(this, MainActivity::class.java).apply {
142	addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
143	}
144	startActivity(intent)
145	}
146	}
147	}
148	}
149	```
150
151	### Registering Watch Service
152
153	Add to the `application` block in `AndroidManifest.xml`:
154
155	```xml
156	<service
157	android:name=".MessageListenerService"
158	android:exported="true">
159	<intent-filter>
160	<action android:name="com.google.android.gms.wearable.MESSAGE_RECEIVED" />
161	<data
162	android:host="*"
163	android:pathPattern=".*"
164	android:scheme="wear" />
165	</intent-filter>
166	</service>
167	```
168
169	### Message Sending Function
170
171	Add to `MainActivity.kt`:
172
173	```kotlin
174	private suspend fun sendMessageToPhone(path: String, data: ByteArray) {
175	val connectedNodes = Wearable.getNodeClient(this).connectedNodes.await()
176	println("Connected nodes: $connectedNodes")
177	for (node in connectedNodes) {
178	try {
179	messageClient.sendMessage(node.id, path, data).await()
180	} catch (e: Exception) {
181	println("Failed to send message to node ${node.id}: ${e.message}")
182	}
183	}
184	}
185	```
186
187	## Final Notes
188
189	- Messages between devices are transferred in `ByteArray` format - remember to encode data in sender device and decode the data in receiver device
190	- For cross-platform frameworks, you can call `sendMessageToWatch` using [MethodChannel](https://api.flutter.dev/flutter/services/MethodChannel-class.html) or equivalent
191	- Name of services should match the name specified in `AndroidManifest.xml`

replaced music ai with aerodd41bdaa year ago191 lines · 6.3 KB

1	---
2	title: "Build Wear OS Apps and Connect with Android"
3	summary: "Create Wear OS app and integrate them with Android, covering setup, permissions, and data sync."
4	date: 2025-11-06
5	---
6
7	## Initial Setup
8
9	Start by creating an android app using your preferred framework and open your project in Android Studio (open the `android` folder if using cross-platform frameworks).
10
11	## Phone App Setup
12
13	First, we need to bind a listener so we can listen to messages sent by our watch even when our app is closed/killed. This requires adding permissions and implementing the package. Don't worry about prompting users for permissions - its not needed as it is a [normal](https://developer.android.com/guide/topics/permissions/overview#normal) permission.
14
15	### Adding Dependencies
16
17	Add the following to your app level gradle file (`app/build.gradle`):
18
19	```kotlin
20	implementation("com.google.android.gms:play-services-wearable:19.0.0")
21	```
22
23	Don't forget to press `Sync Now`
24
25	### Permissions Setup
26
27	Add the following code in the `manifest` block of `AndroidManifest.xml`:
28
29	```xml
30	<uses-permission android:name="com.google.android.wearable.permission.BIND_WEARABLE_LISTENER" />
31	```
32
33	### Creating Message Receiver
34
35	Now, we'll write a service that will be `android:exported`. Create a new file `WearMessageReceiver.kt` in the same folder as `MainActivity.kt`:
36
37	```kotlin
38	package com.your.package
39
40	import android.content.Intent
41	import com.google.android.gms.wearable.MessageEvent
42	import com.google.android.gms.wearable.WearableListenerService
43
44	class WearMessageReceiver : WearableListenerService() {
45	override fun onMessageReceived(event: MessageEvent) {
46	when (event.path) {
47	"/open" -> {
48	val intent = packageManager.getLaunchIntentForPackage(packageName)?.apply {
49	addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
50	addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)
51	}
52	startActivity(intent)
53	}
54	}
55	}
56	}
57	```
58
59	The above code listens for the `/open` message and when received, it opens the app.
60
61	### Registering the Service
62
63	We need to tell our phone about this service. Add the following code in the `application` block of `AndroidManifest.xml`:
64
65	```xml
66	<service
67	android:name="[package name].WearMessageReceiver"
68	android:exported="true">
69	<intent-filter>
70	<action android:name="com.google.android.gms.wearable.MESSAGE_RECEIVED" />
71	<category android:name="android.intent.category.DEFAULT" />
72	<data
73	android:host="*"
74	android:pathPattern=".*"
75	android:scheme="wear" />
76	</intent-filter>
77	</service>
78	```
79
80	### Message Sending Function
81
82	This function sends messages from our phone to the watch. Add it to `MainActivity.kt`:
83
84	```kotlin
85	suspend fun sendMessageToWatch(
86	context: Context,
87	path: String,
88	data: ByteArray = ByteArray(0)
89	) {
90	withContext(Dispatchers.IO) {
91	try {
92	val nodes = Tasks.await(Wearable.getNodeClient(context).connectedNodes)
93	// it is recommended to filter out nodes with `isNearby = false`
94	nodes.forEach { node ->
95	Tasks.await(
96	Wearable.getMessageClient(context).sendMessage(
97	node.id,
98	path,
99	data,
100	)
101	)
102	}
103	} catch (e: Exception) {
104	e.printStackTrace()
105	}
106	}
107	}
108	```
109
110	Read more on suspend functions [here](https://kotlinlang.org/docs/composing-suspending-functions.html).
111
112	## Watch App Setup
113
114	Here, you'll need a Wear OS device connected to your phone and connected to your PC via wireless debugging. Don't have a Wear OS device? No problem! Create a new emulator and run it following the setup instructions. Unlike Apple Watch simulator, it will connect to your physical phone or emulator.
115
116	### Creating the Watch Project
117
118	1. Go to `Android Studio > File > New > New Project > Wear OS > Empty Wear App`
119	2. Keep the bundle identifier same as your phone app
120	3. Connect a Wear OS device or create an emulator
121
122	### Adding Permissions
123
124	Just like the phone app, we need to bind a listener and add permissions. Add to the `manifest` block in `AndroidManifest.xml`:
125
126	```xml
127	<uses-permission android:name="com.google.android.wearable.permission.BIND_WEARABLE_LISTENER" />
128	```
129
130	### Creating Message Listener
131
132	Create `MessageListenerService.kt`:
133
134	```kotlin
135	// make sure the name of this class matches the one in AndroidManifest.xml
136	class MessageListenerService : WearableListenerService() {
137	override fun onMessageReceived(event: MessageEvent) {
138	super.onMessageReceived(event)
139	when (event.path) {
140	"/boot" -> {
141	val intent = Intent(this, MainActivity::class.java).apply {
142	addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
143	}
144	startActivity(intent)
145	}
146	}
147	}
148	}
149	```
150
151	### Registering Watch Service
152
153	Add to the `application` block in `AndroidManifest.xml`:
154
155	```xml
156	<service
157	android:name=".MessageListenerService"
158	android:exported="true">
159	<intent-filter>
160	<action android:name="com.google.android.gms.wearable.MESSAGE_RECEIVED" />
161	<data
162	android:host="*"
163	android:pathPattern=".*"
164	android:scheme="wear" />
165	</intent-filter>
166	</service>
167	```
168
169	### Message Sending Function
170
171	Add to `MainActivity.kt`:
172
173	```kotlin
174	private suspend fun sendMessageToPhone(path: String, data: ByteArray) {
175	val connectedNodes = Wearable.getNodeClient(this).connectedNodes.await()
176	println("Connected nodes: $connectedNodes")
177	for (node in connectedNodes) {
178	try {
179	messageClient.sendMessage(node.id, path, data).await()
180	} catch (e: Exception) {
181	println("Failed to send message to node ${node.id}: ${e.message}")
182	}
183	}
184	}
185	```
186
187	## Final Notes
188
189	- Messages between devices are transferred in `ByteArray` format - remember to encode data in sender device and decode the data in receiver device
190	- For cross-platform frameworks, you can call `sendMessageToWatch` using [MethodChannel](https://api.flutter.dev/flutter/services/MethodChannel-class.html) or equivalent
191	- Name of services should match the name specified in `AndroidManifest.xml`