flutter_sms_scheduler 0.0.1

A Flutter plugin for scheduling SMS messages to be sent at a specific time on Android.

flutter_sms_scheduler

A Flutter plugin to schedule SMS messages to be sent at a specific time on Android.

Features

• Schedule SMS messages to be sent at a future date and time.
• Leverages Android's AlarmManager for scheduling and SmsManager for sending.

Getting Started

This plugin currently supports Android only.

Installation

1. Add flutter_sms_scheduler as a dependency in your pubspec.yaml file:

   dependencies:
     flutter: 
       sdk: flutter
     flutter_sms_scheduler:
       path: ../ # Or the appropriate path/version
   

2. Run flutter pub get.

Android Setup

Add the following permissions to your AndroidManifest.xml file located at android/app/src/main/AndroidManifest.xml:

<manifest xmlns:android="http://schemas.android.com/apk/res/android" ...>
    <!-- Required to send SMS -->
    <uses-permission android:name="android.permission.SEND_SMS" />
    <!-- Required to schedule exact alarms (essential for scheduling) -->
    <uses-permission android:name="android.permission.SCHEDULE_EXACT_ALARM" />
    <!-- Optional: Required if you want to reschedule alarms after device reboot -->
    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />

    <application ...>
        <activity ...>
            ...
        </activity>

        <!-- Add the receiver for handling the scheduled alarm -->
        <receiver android:name="com.example.flutter_sms_scheduler.AlarmReceiver"
                  android:exported="true">
            <intent-filter>
                <action android:name="SEND_SCHEDULED_SMS" />
            </intent-filter>
        </receiver>

        <!-- Optional: Add receiver for boot completed to reschedule alarms -->
        <!-- 
        <receiver android:name=".BootReceiver" android:enabled="true" android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.BOOT_COMPLETED"></action>
            </intent-filter>
        </receiver>
        -->

    </application>
</manifest>

Note:

• Requesting SEND_SMS permission at runtime is crucial before attempting to schedule or send SMS.
• Handling the SCHEDULE_EXACT_ALARM permission might be necessary for Android 12 (API 31) and above. Check Android documentation for details.
• Implementing the BootReceiver (commented out above) is necessary if you need scheduled messages to persist after the device restarts.

Usage

Import the package:

import 'package:flutter_sms_scheduler/flutter_sms_scheduler.dart';

Schedule an SMS:

import 'package:flutter/material.dart';
import 'package:flutter_sms_scheduler/flutter_sms_scheduler.dart';
import 'package:permission_handler/permission_handler.dart'; // Example using permission_handler

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('SMS Scheduler Example'),
        ),
        body: Center(
          child: ElevatedButton(
            onPressed: _scheduleSms,
            child: Text('Schedule SMS in 5 minutes'),
          ),
        ),
      ),
    );
  }

  Future<void> _scheduleSms() async {
    // 1. Request Permissions (Example using permission_handler)
    if (await Permission.sms.request().isGranted && 
        await Permission.scheduleExactAlarm.request().isGranted) { // Check/Request necessary permissions

      final String phoneNumber = '[phone]'; // Replace with target phone number
      final String message = 'This is a scheduled SMS!';
      // Schedule 5 minutes from now
      final DateTime scheduledTime = DateTime.now().add(const Duration(minutes: 5)); 

      try {
        await FlutterSmsScheduler.scheduleSms(
          phoneNumber: phoneNumber,
          message: message,
          scheduledTimeMillis: scheduledTime.millisecondsSinceEpoch,
        );
        print('SMS scheduled successfully for $scheduledTime');
        // Show confirmation to the user
      } catch (e) {
        print('Error scheduling SMS: $e');
        // Show error message to the user
      }
    } else {
      print('Required permissions not granted.');
      // Inform user that permissions are needed
    }
  }
}

Important Notes

• Android Only: This plugin currently only supports the Android platform.
• Permissions: Ensure you have requested and been granted the necessary SEND_SMS and SCHEDULE_EXACT_ALARM permissions before calling scheduleSms.
• Background Execution: SMS sending relies on Android's AlarmManager. Delivery depends on the device's state and battery optimization settings. Some manufacturers have aggressive background restrictions that might affect exact timing.
• Reboot Persistence: By default, scheduled alarms are cleared when the device reboots. To make them persistent, you need to implement a BroadcastReceiver that listens for BOOT_COMPLETED and reschedules the alarms (see commented-out section in AndroidManifest.xml example).
• Error Handling: Implement proper error handling for permission denials and scheduling failures.

Contributing

Contributions are welcome! Please feel free to submit pull requests or open issues.