flutter_local_notifications onDidReceiveNotificationResponse不生效

如果 `onDidReceiveNotificationResponse` 方法没有被调用，那么可能是由于以下原因之一：

1. 没有在初始化时设置 `onDidReceiveNotificationResponse` 回调。请确保在 `FlutterLocalNotificationsPlugin` 的初始化方法中设置了此回调，例如：

FlutterLocalNotificationsPlugin flutterLocalNotificationsPlugin = FlutterLocalNotificationsPlugin();

Future<void> _initNotifications() async {
  var initializationSettingsAndroid = AndroidInitializationSettings('app_icon');
  var initializationSettingsIOS = IOSInitializationSettings();
  var initializationSettings = InitializationSettings(
      android: initializationSettingsAndroid, iOS: initializationSettingsIOS);
  await flutterLocalNotificationsPlugin.initialize(initializationSettings, onSelectNotification: onSelectNotification);
}

Future<void> onSelectNotification(String payload) async {
  // 在此处处理通知点击事件
}

// 设置 onDidReceiveNotificationResponse 回调方法
flutterLocalNotificationsPlugin.onDidReceiveNotificationResponse.listen((event) async {
  await onSelectNotification(event.payload);
});

2. 在 Android 平台上，需要在 `AndroidManifest.xml` 文件中注册 `NotificationReceiver`，并将其与 `FlutterLocalNotificationsPlugin` 相关联。请确保在 `AndroidManifest.xml` 文件中添加以下代码：

<application ...>
    <receiver android:name="com.dexterous.flutterlocalnotifications.ScheduledNotificationReceiver" />
    <receiver android:name="com.dexterous.flutterlocalnotifications.ScheduledNotificationBootReceiver">
        <intent-filter>
            <action android:name="android.intent.action.BOOT_COMPLETED"></action>
        </intent-filter>
    </receiver>
</application>

3. 在 iOS 平台上，需要在 `AppDelegate.swift` 文件中添加以下代码：

import UIKit
import Flutter
import UserNotifications

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate, UNUserNotificationCenterDelegate {
    
    override func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        // 在此处初始化 FlutterLocalNotificationsPlugin
        
        // 设置 UNUserNotificationCenterDelegate
        UNUserNotificationCenter.current().delegate = self
        
        return super.application(application, didFinishLaunchingWithOptions: launchOptions)
    }
    
    // 实现 didReceive response 方法
    func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
        let flutterChannel = FlutterMethodChannel(name: "com.example.app/notification", binaryMessenger: self.window.rootViewController as! FlutterViewController)
        flutterChannel.invokeMethod("onSelectNotification", arguments: response.notification.request.content.userInfo)
        completionHandler()
    }
}

上述代码中，我们通过实现 `UNUserNotificationCenterDelegate` 协议的 `didReceive response` 方法来处理通知的点击事件，并且调用了 `FlutterMethodChannel` 方法来将通知的 payload 发送给 Flutter 端的 `onSelectNotification` 方法。

希望这些信息能对你有所帮助！