For #3317: Prepopulate FxA device name field with existing name (#3733)

app/src/main/java/org/mozilla/fenix/components/BackgroundServices.kt

@@ -5,6 +5,7 @@
 package org.mozilla.fenix.components
 
 import android.content.Context
+import android.os.Build
 import androidx.lifecycle.ProcessLifecycleOwner
 import androidx.work.WorkManager
 import kotlinx.coroutines.CoroutineScope
@@ -24,7 +25,6 @@ import mozilla.components.service.fxa.manager.FxaAccountManager
 import mozilla.components.support.base.log.logger.Logger
 import org.mozilla.fenix.BuildConfig
 import org.mozilla.fenix.Experiments
-import org.mozilla.fenix.R
 import org.mozilla.fenix.isInExperiment
 import org.mozilla.fenix.test.Mockable
 
@@ -87,11 +87,13 @@ class BackgroundServices(
         emptyList()
     }
 
+    private val defaultDeviceName = Build.MANUFACTURER + " " + Build.MODEL
+
     val accountManager = FxaAccountManager(
         context,
         config,
         scopes,
-        DeviceTuple(context.getString(R.string.app_name), DeviceType.MOBILE, deviceCapabilities),
+        DeviceTuple(defaultDeviceName, DeviceType.MOBILE, deviceCapabilities),
         syncManager
     ).also {
         it.registerForDeviceEvents(deviceEventObserver, ProcessLifecycleOwner.get(), true)

app/src/main/java/org/mozilla/fenix/settings/AccountSettingsFragment.kt

@@ -31,6 +31,7 @@ import mozilla.components.service.fxa.FxaPanicException
 import mozilla.components.service.fxa.manager.FxaAccountManager
 import mozilla.components.support.base.log.logger.Logger
 import org.mozilla.fenix.R
+import org.mozilla.fenix.components.FenixSnackbar
 import org.mozilla.fenix.components.metrics.Event
 import org.mozilla.fenix.ext.getPreferenceKey
 import org.mozilla.fenix.ext.requireComponents
@@ -117,6 +118,7 @@ class AccountSettingsFragment : PreferenceFragmentCompat() {
             onPreferenceChangeListener = getChangeListenerForDeviceName()
             deviceConstellation?.state()?.currentDevice?.let { device ->
                 summary = device.displayName
+                text = device.displayName
             }
             setOnBindEditTextListener { editText ->
                 editText.filters = arrayOf(InputFilter.LengthFilter(DEVICE_NAME_MAX_LENGTH))
@@ -158,6 +160,13 @@ class AccountSettingsFragment : PreferenceFragmentCompat() {
 
     private fun getChangeListenerForDeviceName(): Preference.OnPreferenceChangeListener {
         return Preference.OnPreferenceChangeListener { _, newValue ->
+            // The network request requires a nonempty string, so don't persist any changes if the user inputs one.
+            if (newValue.toString().trim().isEmpty()) {
+                FenixSnackbar.make(view!!, FenixSnackbar.LENGTH_LONG)
+                    .setText(getString(R.string.empty_device_name_error))
+                    .show()
+                return@OnPreferenceChangeListener false
+            }
             // Optimistically set the device name to what user requested.
             val deviceNameKey = context!!.getPreferenceKey(R.string.pref_key_sync_device_name)
             val preferenceDeviceName = findPreference<Preference>(deviceNameKey)
@@ -175,7 +184,6 @@ class AccountSettingsFragment : PreferenceFragmentCompat() {
                     Logger.error("Setting device name failed.", e)
                 }
             }
-
             true
         }
     }

app/src/main/res/values/strings.xml

@@ -155,6 +155,8 @@
     <string name="preferences_sign_out">Sign out</string>
     <!-- Preference displays and allows changing current FxA device name -->
     <string name="preferences_sync_device_name">Device name</string>
+    <!-- Text shown when user enters empty device name -->
+    <string name="empty_device_name_error">Device name cannot be empty.</string>
     <!-- Label indicating that sync is in progress -->
     <string name="sync_syncing_in_progress">Syncing…</string>
     <!-- Label summary indicating that sync failed. The first parameter is the date stamp showing last time it succeeded -->