Pianificazione delle notifiche locali
Installi expo-notifications, richieda l’autorizzazione, pianifichi una notifica locale da inviare dopo un ritardo e gestisca il tocco sulla notifica per navigare verso una schermata specifica.
Pianificazione delle notifiche locali è una lezione React Native Academy gratuita su CoddyKit. Questa è la lezione 3 di 4. Puoi leggere la lezione completa qui gratuitamente — poi esercitati direttamente nel browser con un editor di codice integrato e un tutor IA disponibile 24/7. Fa parte del percorso di apprendimento React Native Academy, e i tuoi progressi si sincronizzano tra il web e l'app CoddyKit. Il corso React Native Academy include 4 lezioni in totale.
Parti di questa lezione non sono ancora state tradotte e vengono mostrate in inglese.
What Are Local Notifications?
Local notifications are alerts that your app schedules and delivers entirely on-device, without a server. Unlike push notifications, they do not require an internet connection or a backend service. They are ideal for reminders, daily habit prompts, timer alerts, and in-app alerts that trigger after a specific time or based on a recurring schedule.
Installing expo-notifications
Install expo-notifications using the Expo install command so the SDK-compatible version is selected. In managed Expo projects native linking is automatic. Also add the notification configuration block to app.json to set the Android notification icon and color used by the OS.
npx expo install expo-notifications
// app.json:
{
"expo": {
"notification": {
"icon": "./assets/notification-icon.png",
"color": "#6200ee",
"androidMode": "default"
}
}
}Requesting Notification Permission
On both iOS and Android you must request notification permission before scheduling any notification. iOS requires explicit user approval — the system shows a dialog. Android 13+ also requires runtime permission. Call Notifications.requestPermissionsAsync() and check whether status is 'granted' before proceeding.
import * as Notifications from 'expo-notifications';
async function requestNotificationPermission() {
const { status } = await Notifications.requestPermissionsAsync();
if (status !== 'granted') {
Alert.alert(
'Permission Denied',
'Enable notifications in Settings to receive reminders.'
);
return false;
}
return true;
}Setting a Default Notification Handler
Set a global notification handler with Notifications.setNotificationHandler to control how notifications behave when the app is in the foreground. Without this, notifications delivered while your app is open are silently ignored on iOS. Call it once at the module level (outside any component) so it is always active.
import * as Notifications from 'expo-notifications';
Notifications.setNotificationHandler({
handleNotification: async () => ({
shouldShowAlert: true, // show banner while app is open
shouldPlaySound: true,
shouldSetBadge: false,
}),
});Scheduling a One-Time Notification
Notifications.scheduleNotificationAsync schedules a notification to be delivered at a specific time. The trigger can be a number of seconds from now, a specific Date object, or a repeating calendar trigger. The function returns a unique notification identifier that you can use later to cancel the notification if needed.
async function scheduleReminder() {
const hasPermission = await requestNotificationPermission();
if (!hasPermission) return;
const id = await Notifications.scheduleNotificationAsync({
content: {
title: 'Daily Reminder',
body: 'Time to check your goals for today!',
sound: true,
data: { screen: 'Goals' }, // custom data for handling the tap
},
trigger: {
seconds: 60, // deliver in 60 seconds
},
});
console.log('Notification scheduled with ID:', id);
}Scheduling a Recurring Notification
To schedule a repeating notification — for example a daily 8 AM reminder — use a calendar trigger with a repeats: true flag. Specify the hour, minute, and optionally day-of-week to create any recurring pattern. The OS delivers the notification at the specified time and automatically reschedules it for the next occurrence.
await Notifications.scheduleNotificationAsync({
content: {
title: 'Good morning!',
body: 'Your daily coding practice is waiting.',
},
trigger: {
type: Notifications.SchedulableTriggerInputTypes.CALENDAR,
hour: 8,
minute: 0,
repeats: true, // fires every day at 8:00 AM
},
});Cancelling a Scheduled Notification
Save the notification identifier returned by scheduleNotificationAsync (e.g., in state or AsyncStorage) so you can cancel it later. Call Notifications.cancelScheduledNotificationAsync(id) with the saved ID to cancel a specific notification. Use cancelAllScheduledNotificationsAsync() to cancel all pending notifications at once.
const [notifId, setNotifId] = React.useState<string | null>(null);
async function cancelReminder() {
if (notifId) {
await Notifications.cancelScheduledNotificationAsync(notifId);
setNotifId(null);
console.log('Notification cancelled');
}
}
// Or cancel all at once:
await Notifications.cancelAllScheduledNotificationsAsync();Handling Foreground Notifications
Use Notifications.addNotificationReceivedListener to react when a notification arrives while the app is open. This is useful for updating in-app badges, playing a custom sound, or refreshing a data feed. Always remove the listener in the useEffect cleanup to prevent memory leaks.
useEffect(() => {
const subscription = Notifications.addNotificationReceivedListener(
(notification) => {
console.log('Received:', notification.request.content.title);
const screen = notification.request.content.data?.screen;
if (screen) setBadge(screen);
}
);
return () => subscription.remove();
}, []);Handling Notification Taps
Use Notifications.addNotificationResponseReceivedListener to handle when the user taps a notification banner. This callback fires whether the app was in the foreground, background, or closed. Use the custom data field you attached when scheduling to navigate to the correct screen in your app.
useEffect(() => {
const subscription = Notifications.addNotificationResponseReceivedListener(
(response) => {
const screen = response.notification.request.content.data?.screen;
if (screen && navigationRef.current) {
navigationRef.current.navigate(screen);
}
}
);
return () => subscription.remove();
}, []);Getting All Scheduled Notifications
Call Notifications.getAllScheduledNotificationsAsync() to retrieve a list of all pending scheduled notifications. This is useful for debugging, for showing a 'Reminders' management screen where users can review and delete scheduled notifications, or for preventing duplicate scheduling if the user reopens the settings screen.
async function listScheduledNotifications() {
const scheduled = await Notifications.getAllScheduledNotificationsAsync();
console.log('Pending notifications:', scheduled.length);
scheduled.forEach((notif) => {
console.log(
notif.identifier,
notif.content.title,
JSON.stringify(notif.trigger)
);
});
}Badges and Android Channels
On iOS, set the app badge number with Notifications.setBadgeCountAsync(count). On Android 8+, notifications must be assigned to a notification channel which controls sound, vibration, and importance. Create a channel once on app startup using Notifications.setNotificationChannelAsync and reference its ID in your notification's channelId field.
if (Platform.OS === 'android') {
await Notifications.setNotificationChannelAsync('reminders', {
name: 'Reminders',
importance: Notifications.AndroidImportance.HIGH,
vibrationPattern: [0, 250, 250, 250],
sound: 'default',
});
}
// Reference in notification:
await Notifications.scheduleNotificationAsync({
content: { title: 'Reminder', channelId: 'reminders' },
trigger: { seconds: 30 },
});Quick Check
Test your understanding of React Native Mobile Development concepts from this lesson.
Lesson Recap
In this lesson you learned: requestPermissionsAsync must be granted before any notification can appear, scheduleNotificationAsync with a trigger delivers one-time or repeating notifications at specified times, and addNotificationResponseReceivedListener handles user taps to navigate to the right screen. Next up we explore handling permissions gracefully.
Domande Frequenti
La lezione «Pianificazione delle notifiche locali» è gratuita?
Sì — il testo completo di «Pianificazione delle notifiche locali» è gratuito qui sul web. Per esercitarvi in modo interattivo (un editor di codice integrato e un tutor IA 24/7) e sbloccare il resto del corso React Native Academy, passa a CoddyKit PRO. Il corso React Native Academy include 4 lezioni in totale.
Cosa imparerò in «Pianificazione delle notifiche locali»?
Installi expo-notifications, richieda l’autorizzazione, pianifichi una notifica locale da inviare dopo un ritardo e gestisca il tocco sulla notifica per navigare verso una schermata specifica. Eserciti React Native Academy con codice pratico che esegui direttamente nel browser, e un tutor IA 24/7 risponde alle tue domande mentre lavori sulla lezione.
Ho bisogno di esperienza per iniziare React Native Academy?
Non è richiesta alcuna esperienza precedente. React Native Academy su CoddyKit è strutturato per principianti e studenti avanzati, quindi puoi iniziare da qui o dall'inizio e procedere al tuo ritmo. Questa è la lezione 3 di 4.
Quanto tempo richiede la lezione «Pianificazione delle notifiche locali»?
La maggior parte delle lezioni CoddyKit richiede circa 5–10 minuti. Ogni lezione è breve e interattiva, quindi fai progressi costanti e riprendi esattamente da dove hai lasciato su web e app.
Posso scrivere ed eseguire codice in questa lezione React Native Academy?
Sì. Ogni lezione React Native Academy include un editor di codice integrato, quindi scrivi ed esegui codice reale direttamente nel tuo browser e ricevi feedback istantaneo dall'IA — nessuna configurazione locale necessaria.
Tutte le lezioni di questo corso
- Accesso alla fotocamera con expo-camera
- Lettura della posizione GPS con expo-location
- Pianificazione delle notifiche locali
- Gestione corretta delle autorizzazioni