如何基于react-native-push-notification在React Native（仅安卓）启用本地全屏通知

Hey there! I've dealt with this exact issue before using react-native-push-notification for local fullscreen notifications, so let me walk you through the steps that worked for me with the latest library versions (v8.x+). The key is that fullscreen behavior differs between Android and iOS, so we'll cover both platforms separately.

Android requires a high-priority notification channel and explicit enablement of the full-screen intent to trigger that immersive alert.

1. Create a High-Priority Notification Channel
   Android O and above mandate notification channels, and fullscreen alerts need the highest importance level. Add this code when initializing your app:

   import PushNotification from 'react-native-push-notification';
   
   PushNotification.createChannel(
     {
       channelId: "fullscreen_local_channel", // Unique ID for the channel
       channelName: "Fullscreen Local Alerts",
       channelDescription: "Channel dedicated to fullscreen local notifications",
       importance: 5, // Maps to Android's IMPORTANCE_HIGH (required for fullscreen)
       vibrate: true,
     },
     (created) => console.log(`Fullscreen channel created: ${created}`)
   );
   

2. Send the Fullscreen Local Notification
   When triggering your local notification, specify the channel you created and enable fullScreenIntent:

   PushNotification.localNotification({
     channelId: "fullscreen_local_channel",
     title: "Urgent Alert",
     message: "This is a fullscreen local notification",
     fullScreenIntent: true, // Critical flag to enable fullscreen behavior
     priority: "high",
     // Optional: Add a big image for a more immersive fullscreen view
     // customBigPicture: require("./assets/urgent_alert_banner.png")
   });
   

3. Request Required Permissions (Android 12+)
   Android 12 and above require the POST_NOTIFICATIONS permission. Add this helper function to request it early in your app:

   import { PermissionsAndroid, Platform } from 'react-native';
   
   async function requestFullscreenNotificationPermission() {
     if (Platform.OS === 'android') {
       const granted = await PermissionsAndroid.request(
         PermissionsAndroid.PERMISSIONS.POST_NOTIFICATIONS,
         {
           title: "Notification Access",
           message: "We need notification permissions to show fullscreen alerts",
           buttonPositive: "Allow",
           buttonNegative: "Cancel"
         }
       );
       return granted === PermissionsAndroid.RESULTS.GRANTED;
     }
     return true;
   }
   
   // Call this function when your app loads
   requestFullscreenNotificationPermission();
   

iOS handles fullscreen notifications via interruption levels and alert configurations. For most use cases, the "time-sensitive" level works without extra Apple permissions.

1. Update Info.plist Permissions
   Add these entries to your Info.plist to enable alert permissions:

   <key>NSUserNotificationUsageDescription</key>
   <string>We need notification access to show urgent fullscreen alerts</string>
   <key>NSAlertUsageDescription</key>
   <string>Alerts help us notify you of critical updates</string>
   <key>UIBackgroundModes</key>
   <array>
     <string>remote-notification</string>
   </array>
   

2. Send the Fullscreen Local Notification
   Use the interruptionLevel property to trigger a fullscreen alert (works best when the device is locked):

   PushNotification.localNotification({
     title: "Urgent iOS Alert",
     message: "This is a fullscreen local notification on iOS",
     ios: {
       interruptionLevel: "time-sensitive", // Triggers fullscreen on lock screen
       presentAlert: true,
       presentSound: true,
       presentBadge: false,
       // Optional: For custom fullscreen UI, define a category and use a Notification Content Extension
       // category: "FULLSCREEN_ALERT_CATEGORY"
     }
   });
   

   • If you need a critical alert (bypasses Do Not Disturb), you'll need to request special permission from Apple and set interruptionLevel: "critical".

• Update the Library: Make sure you're on the latest version of react-native-push-notification (v8.x+). Older versions lack the fullScreenIntent flag for Android. Run npm install react-native-push-notification@latest to update.
• Test on Lock Screen: Fullscreen notifications typically only trigger when the device is locked—test in that state first.
• Verify Channel Creation: On Android, if the channel isn't created successfully, the notification will fall back to default behavior. Check the console log from the createChannel callback to confirm it's created.

内容的提问来源于stack exchange，提问作者CodeJoe