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jdkorenjdkoren
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Implement bound service with foreground notification
Bug: 210514977 Change-Id: I9b739992f82739489f0835f4c6b07db4f1f436c4
1 parent f1c2907 commit c81d2b9

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‎ForegroundLocationUpdates/app/build.gradle‎

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@@ -71,6 +71,7 @@ dependencies {
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implementation 'androidx.core:core-ktx:1.7.0'
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implementation "androidx.datastore:datastore-preferences:1.0.0"
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implementation 'androidx.lifecycle:lifecycle-runtime-ktx:2.4.0'
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implementation 'androidx.lifecycle:lifecycle-service:2.4.0'
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implementation 'com.google.android.material:material:1.4.0'
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‎ForegroundLocationUpdates/app/src/main/AndroidManifest.xml‎

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-->
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<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
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<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
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<uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
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<application
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android:name=".ForegroundLocationApp"
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<category android:name="android.intent.category.LAUNCHER" />
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</intent-filter>
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</activity>
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<service android:name=".ForegroundLocationService" android:exported="false" />
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</application>
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</manifest>

‎ForegroundLocationUpdates/app/src/main/java/com/google/android/gms/location/sample/foregroundlocation/ForegroundLocationService.kt‎

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/*
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* Copyright (C) 2021 Google Inc.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* https://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package com.google.android.gms.location.sample.foregroundlocation
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import android.Manifest.permission
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import android.app.Notification
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import android.app.NotificationChannel
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import android.app.NotificationManager
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import android.app.PendingIntent
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import android.content.ComponentName
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import android.content.Intent
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import android.content.ServiceConnection
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import android.location.Location
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import android.os.Binder
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import android.os.Build.VERSION
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import android.os.Build.VERSION_CODES
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import android.os.IBinder
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import androidx.core.app.NotificationCompat
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import androidx.lifecycle.LifecycleService
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import androidx.lifecycle.lifecycleScope
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import com.google.android.gms.location.sample.foregroundlocation.ForegroundLocationService.LocalBinder
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import com.google.android.gms.location.sample.foregroundlocation.data.LocationPreferences
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import com.google.android.gms.location.sample.foregroundlocation.data.LocationRepository
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import com.google.android.gms.location.sample.foregroundlocation.ui.hasPermission
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import dagger.hilt.android.AndroidEntryPoint
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import kotlinx.coroutines.delay
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import kotlinx.coroutines.flow.collect
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import kotlinx.coroutines.flow.first
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import kotlinx.coroutines.launch
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import javax.inject.Inject
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/**
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* Service which manages turning location updates on and off. UI clients should bind to this service
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* to access this functionality.
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*
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* This service can be started the usual way (i.e. startService), but it will also start itself when
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* the first client binds to it. Thereafter it will manage its own lifetime as follows:
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* - While there are any bound clients, the service remains started in the background. If it was
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* in the foreground, it will exit the foreground, cancelling any ongoing notification.
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* - When there are no bound clients and location updates are on, the service moves to the
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* foreground and shows an ongoing notification with the latest location.
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* - When there are no bound clients and location updates are off, the service stops itself.
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*/
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@AndroidEntryPoint
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class ForegroundLocationService : LifecycleService() {
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@Inject
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lateinit var locationRepository: LocationRepository
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@Inject
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lateinit var locationPreferences: LocationPreferences
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private val localBinder = LocalBinder()
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private var bindCount = 0
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private var started = false
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private var isForeground = false
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private fun isBound() = bindCount > 0
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override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
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super.onStartCommand(intent, flags, startId)
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// Startup tasks only happen once.
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if (!started) {
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started = true
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// Check if we should turn on location updates.
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lifecycleScope.launch {
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if (locationPreferences.isLocationTurnedOn.first()) {
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// If the service is restarted for any reason, we may have lost permission to
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// access location since last time. In that case we won't turn updates on here,
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// and the service will stop when we manage its lifetime below. Then the user
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// will have to open the app to turn updates on again.
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if (hasPermission(permission.ACCESS_FINE_LOCATION) ||
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hasPermission(permission.ACCESS_COARSE_LOCATION)
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) {
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locationRepository.startLocationUpdates()
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}
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}
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}
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// Update any foreground notification when we receive location updates.
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lifecycleScope.launch {
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locationRepository.lastLocation.collect(::showNotification)
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}
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}
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// Decide whether to remain in the background, promote to the foreground, or stop.
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manageLifetime()
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// In case we are stopped by the system, have the system restart this service so we can
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// manage our lifetime appropriately.
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return START_STICKY
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}
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override fun onBind(intent: Intent): IBinder {
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super.onBind(intent)
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handleBind()
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return localBinder
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}
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override fun onRebind(intent: Intent?) {
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handleBind()
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}
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private fun handleBind() {
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bindCount++
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// Start ourself. This will let us manage our lifetime separately from bound clients.
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startService(Intent(this, this::class.java))
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}
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override fun onUnbind(intent: Intent?): Boolean {
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bindCount--
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lifecycleScope.launch {
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// UI client can unbind because it went through a configuration change, in which case it
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// will be recreated and bind again shortly. Wait a few seconds, and if still not bound,
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// manage our lifetime accordingly.
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delay(UNBIND_DELAY_MILLIS)
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manageLifetime()
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}
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// Allow clients to rebind, in which case onRebind will be called.
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return true
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}
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private fun manageLifetime() {
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when {
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// We should not be in the foreground while UI clients are bound.
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isBound() -> exitForeground()
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// Location updates were started.
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locationRepository.isReceivingLocationUpdates.value -> enterForeground()
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// Nothing to do, so we can stop.
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else -> stopSelf()
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}
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}
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private fun exitForeground() {
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if (isForeground) {
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isForeground = false
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stopForeground(true)
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}
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}
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private fun enterForeground() {
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if (!isForeground) {
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isForeground = true
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// Show notification with the latest location.
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showNotification(locationRepository.lastLocation.value)
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}
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}
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private fun showNotification(location: Location?) {
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if (!isForeground) {
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return
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}
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createNotificationChannel()
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startForeground(NOTIFICATION_ID, buildNotification(location))
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}
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private fun createNotificationChannel() {
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if (VERSION.SDK_INT >= VERSION_CODES.O) {
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val notificationChannel = NotificationChannel(
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NOTIFICATION_CHANNEL_ID,
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getString(R.string.notification_channel_name),
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NotificationManager.IMPORTANCE_DEFAULT
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)
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val manager = getSystemService(NOTIFICATION_SERVICE) as NotificationManager
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manager.createNotificationChannel(notificationChannel)
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}
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}
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private fun buildNotification(location: Location?) : Notification {
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// Tapping the notification opens the app.
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val pendingIntent = PendingIntent.getActivity(
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this,
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0,
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packageManager.getLaunchIntentForPackage(this.packageName),
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PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE
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)
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val contentText = if (location != null) {
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getString(R.string.location_lat_lng, location.latitude, location.longitude)
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} else {
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getString(R.string.waiting_for_location)
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}
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return NotificationCompat.Builder(this, NOTIFICATION_CHANNEL_ID)
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.setContentTitle(getString(R.string.notification_title))
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.setContentText(contentText)
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.setContentIntent(pendingIntent)
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.setSmallIcon(R.drawable.ic_location)
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.setOngoing(true)
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.setCategory(NotificationCompat.CATEGORY_SERVICE)
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.setPriority(NotificationCompat.PRIORITY_DEFAULT)
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.setVisibility(NotificationCompat.VISIBILITY_PRIVATE)
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.build()
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}
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// Methods for clients.
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fun startLocationUpdates() {
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locationRepository.startLocationUpdates()
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}
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fun stopLocationUpdates() {
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locationRepository.stopLocationUpdates()
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}
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/** Binder which provides clients access to the service. */
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internal inner class LocalBinder : Binder() {
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fun getService(): ForegroundLocationService = this@ForegroundLocationService
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}
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private companion object {
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const val UNBIND_DELAY_MILLIS = 2000.toLong() // 2 seconds
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const val NOTIFICATION_ID = 1
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const val NOTIFICATION_CHANNEL_ID = "LocationUpdates"
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}
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}
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/**
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* ServiceConnection that provides access to a [ForegroundLocationService].
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*/
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class ForegroundLocationServiceConnection @Inject constructor() : ServiceConnection {
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var service: ForegroundLocationService? = null
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private set
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override fun onServiceConnected(name: ComponentName, binder: IBinder) {
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service = (binder as LocalBinder).getService()
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}
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override fun onServiceDisconnected(name: ComponentName) {
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// Note: this should never be called since the service is in the same process.
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service = null
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}
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}

‎ForegroundLocationUpdates/app/src/main/java/com/google/android/gms/location/sample/foregroundlocation/MainActivity.kt‎

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package com.google.android.gms.location.sample.foregroundlocation
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import android.content.Intent
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import android.os.Bundle
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import androidx.activity.ComponentActivity
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import androidx.activity.compose.setContent
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}
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}
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}
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override fun onStart() {
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super.onStart()
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val serviceIntent = Intent(this, ForegroundLocationService::class.java)
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bindService(serviceIntent, viewModel, BIND_AUTO_CREATE)
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}
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override fun onStop() {
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super.onStop()
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unbindService(viewModel)
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}
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}
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@Composable

‎ForegroundLocationUpdates/app/src/main/java/com/google/android/gms/location/sample/foregroundlocation/MainViewModel.kt‎

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package com.google.android.gms.location.sample.foregroundlocation
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import android.content.ServiceConnection
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import androidx.lifecycle.ViewModel
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import androidx.lifecycle.viewModelScope
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import com.google.android.gms.location.sample.foregroundlocation.PlayServicesAvailableState.Initializing
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@HiltViewModel
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class MainViewModel @Inject constructor(
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playServicesAvailabilityChecker: PlayServicesAvailabilityChecker,
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private val locationRepository: LocationRepository,
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private val locationPreferences: LocationPreferences
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) : ViewModel() {
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locationRepository: LocationRepository,
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private val locationPreferences: LocationPreferences,
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private val serviceConnection: ForegroundLocationServiceConnection
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) : ViewModel(), ServiceConnection by serviceConnection {
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val playServicesAvailableState = flow {
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emit(
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fun toggleLocationUpdates() {
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if (isReceivingLocationUpdates.value) {
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stopLocationUpdates()
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} else {
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startLocationUpdates()
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}
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}
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private fun startLocationUpdates() {
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locationRepository.startLocationUpdates()
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serviceConnection.service?.startLocationUpdates()
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// Store that the user turned on location updates.
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// It's possible that the service was not connected for the above call. In that case, when
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// the service eventually starts, it will check the persisted value and react appropriately.
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viewModelScope.launch {
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locationPreferences.setLocationTurnedOn(true)
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}
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}
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private fun stopLocationUpdates() {
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locationRepository.stopLocationUpdates()
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serviceConnection.service?.stopLocationUpdates()
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// Store that the user turned off location updates.
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// It's possible that the service was not connected for the above call. In that case, when
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// the service eventually starts, it will check the persisted value and react appropriately.
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viewModelScope.launch {
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locationPreferences.setLocationTurnedOn(false)
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}

‎ForegroundLocationUpdates/app/src/main/java/com/google/android/gms/location/sample/foregroundlocation/data/LocationRepository.kt‎

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import kotlinx.coroutines.flow.MutableStateFlow
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import kotlinx.coroutines.flow.asStateFlow
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import javax.inject.Inject
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import javax.inject.Singleton
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@Singleton
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class LocationRepository @Inject constructor(
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private val fusedLocationProviderClient: FusedLocationProviderClient
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) {
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_lastLocation.value = null
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}
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inner class Callback : LocationCallback() {
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private inner class Callback : LocationCallback() {
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override fun onLocationResult(result: LocationResult) {
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_lastLocation.value = result.lastLocation
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}

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