Add a Battery Saver warning to Services

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## Unreleased
 
+- added: Battery Saver warning message for Android
 - added: Buy conversion tracking for Moonpay
 - added: Error tracking for failure to report conversions to referral server
 - changed: Remove whitespaces from custom token contract address input

src/components/services/Services.tsx

@@ -1,6 +1,9 @@
 import { asDate, asJSON, asObject, uncleaner } from 'cleaners'
 import { EdgeAccount } from 'edge-core-js'
 import * as React from 'react'
+import { EmitterSubscription } from 'react-native'
+import { AirshipBridge } from 'react-native-airship'
+import { powerSavingModeChanged, powerSavingOn } from 'react-native-power-saving-mode'
 
 import { updateExchangeInfo } from '../../actions/ExchangeInfoActions'
 import { refreshConnectedWallets } from '../../actions/FioActions'
@@ -11,13 +14,15 @@ import { ENV } from '../../env'
 import { useAsyncEffect } from '../../hooks/useAsyncEffect'
 import { useHandler } from '../../hooks/useHandler'
 import { useRefresher } from '../../hooks/useRefresher'
+import { lstrings } from '../../locales/strings'
 import { defaultAccount } from '../../reducers/CoreReducer'
 import { FooterAccordionEventService } from '../../state/SceneFooterState'
 import { useDispatch, useSelector } from '../../types/reactRedux'
 import { NavigationBase } from '../../types/routerTypes'
 import { height, ratioHorizontal, ratioVertical, width } from '../../util/scaling'
 import { snooze } from '../../util/utils'
 import { FioCreateHandleModal } from '../modals/FioCreateHandleModal'
+import { AlertDropdown } from '../navigation/AlertDropdown'
 import { AccountCallbackManager } from './AccountCallbackManager'
 import { ActionQueueService } from './ActionQueueService'
 import { Airship } from './AirshipInstance'
@@ -123,6 +128,52 @@ export function Services(props: Props) {
     'Services 2'
   )
 
+  // Subscribe to Android Power Saver state, and show a warning only if it
+  // changes from off to on:
+  useAsyncEffect(
+    async () => {
+      // This method is only available for Android
+      if (powerSavingOn == null) return
+
+      let airshipBridge: AirshipBridge<void> | undefined
+      const handlePowerSavingModeChanged = async (isPowerSavingModeOn: boolean) => {
+        if (isPowerSavingModeOn && airshipBridge == null) {
+          await Airship.show(bridge => {
+            airshipBridge = bridge // Capture the bridge here
+            return <AlertDropdown bridge={bridge} message={lstrings.warning_battery_saver} warning persistent />
+          }).then(() => {
+            airshipBridge = undefined
+          })
+        } else if (!isPowerSavingModeOn && airshipBridge != null) {
+          // Dismiss the alert when power-saving mode turns off and there's an
+          // active warning that wasn't dismissed
+          airshipBridge.resolve()
+        }
+      }
+
+      // Show warning if Power Saver mode is on initially on app boot
+      await handlePowerSavingModeChanged(await powerSavingOn())
+
+      // Subscribe to Power Saver mode changes
+      let subscription: EmitterSubscription | undefined
+      if (powerSavingModeChanged != null) {
+        subscription = powerSavingModeChanged(handlePowerSavingModeChanged)
+      }
+
+      // Cleanup
+      return () => {
+        if (subscription != null) {
+          subscription.remove()
+        }
+        if (airshipBridge != null) {
+          airshipBridge.resolve()
+        }
+      }
+    },
+    [],
+    'Services 3'
+  )
+
   // Methods to call periodically
   useRefresher(
     async () => {

src/locales/en_US.ts

@@ -126,6 +126,7 @@ const strings = {
     'The entered contract address differs from the contract address of built-in token %1$s. Please proceed with caution and verify the contract is legitimate as use of this token can result in loss of funds. If you have questions about this feature or contract please contact %2$s.',
   warning_token_exists_1s: 'The entered token already exists as a built-in token %1$s',
   warning_uk_risk: `Don't invest unless you're prepared to lose all the money you invest. This is a high-risk investment and you should not expect to be protected if something goes wrong. Take 2 min to learn more.`,
+  warning_battery_saver: `Battery Saver mode detected. Balances and transactions may be inaccurate`,
 
   // Alert component:
   alert_dropdown_alert: 'Alert! ',

src/locales/strings/enUS.json

@@ -81,6 +81,7 @@
   "warning_token_code_override_2s": "The entered contract address differs from the contract address of built-in token %1$s. Please proceed with caution and verify the contract is legitimate as use of this token can result in loss of funds. If you have questions about this feature or contract please contact %2$s.",
   "warning_token_exists_1s": "The entered token already exists as a built-in token %1$s",
   "warning_uk_risk": "Don't invest unless you're prepared to lose all the money you invest. This is a high-risk investment and you should not expect to be protected if something goes wrong. Take 2 min to learn more.",
+  "warning_battery_saver": "Battery Saver mode detected. Balances and transactions may be inaccurate",
   "alert_dropdown_alert": "Alert! ",
   "alert_dropdown_warning": "Warning! ",
   "azteco_success": "You've redeemed an Azteco bitcoin card. Funds should arrive shortly.",