【问题标题】：Hypertrack is preventing FCM notification in FlutterHypertrack 正在阻止 Flutter 中的 FCM 通知
【发布时间】：2021-02-24 11:54:03
【问题描述】：

当我在 Flutter 中使用 hypertrack_plugin 和 firebase_messaging 时，我无法在 Android 中接收任何消息。但是，它在 iOS 中运行良好。

hypertrack_plugin 版本：0.1.3 firebase_messaging 版本：7.0.3

【问题讨论】：

标签： flutter firebase-cloud-messaging hypertrack

【解决方案1】：

更新

此问题已在 hypertrack_plugin: 0.1.4 版本的插件更新中修复

问题

您正面临此问题，因为有多个从 FirebaseMessagingService 扩展的服务类。因此，消息在一个具有高优先级的类中接收，而不是在另一个类中接收。

解决方案

方法一

将以下内容添加到您的 AndroidManifest.xml 文件中

<service android:name="io.flutter.plugins.firebasemessaging.FlutterFirebaseMessagingService">
      <intent-filter android:priority="100">
            <action android:name="com.google.firebase.MESSAGING_EVENT"/>
      </intent-filter>
</service>

它是如何工作的？

在其清单文件中为FlutterFirebaseMessagingService 设置的优先级为零（默认），但在其清单文件中声明HyperTrackMessagingService 的优先级为5（现在为4.8.0 版）。上面的解决方案只是覆盖了优先级，让传入的消息到达FlutterFirebaseMessagingService，而不是HyperTrackMessagingService。

限制：

虽然 HyperTrack 可以正常工作，但 HyperTrack 使用 FCM 进行设备-服务器通信以进行优化，如果没有 FCM，它将无法运行。但是，您可能没有注意到这一点。

方法二

使用反射将HyperTrackMessagingService 中的传入消息转发到插件hypertrack_plugin 中的FlutterFirebaseMessagingService。

步骤：

您需要下载hypertrack_plugin 源代码并将其用作本地依赖项。 How?
在库sdk-flutter/android/src/main/kotlin/com/hypertrack/sdk/flutter/MyFirebaseMessagingService.java中创建一个新类

package com.hypertrack.sdk.flutter;

import android.annotation.SuppressLint;
import android.util.Log;

import com.google.firebase.messaging.RemoteMessage;
import com.hypertrack.sdk.HyperTrackMessagingService;

import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

@SuppressLint("LongLogTag")
public class MyFirebaseMessagingService extends HyperTrackMessagingService {

    private static final String TAG = "MyFirebaseMessagingService";

    private Class<?> serviceClass;
    private Object serviceObject;

    public MyFirebaseMessagingService() {
        try {
            serviceClass = Class.forName("io.flutter.plugins.firebasemessaging.FlutterFirebaseMessagingService");
            serviceObject = serviceClass.newInstance();
            injectContext();

            Log.d(TAG, "io.flutter.plugins.firebasemessaging.FlutterFirebaseMessagingService is found");
        } catch (Throwable t) {
            Log.w(TAG, "Can't find the class io.flutter.plugins.firebasemessaging.FlutterFirebaseMessagingService", t);
        }
    }

    @Override
    public void onNewToken(final String s) {
        super.onNewToken(s);
        injectToken(s);
    }

    @Override
    public void onMessageReceived(final RemoteMessage remoteMessage) {
        super.onMessageReceived(remoteMessage);
        injectMessage(remoteMessage);
    }

    public void injectToken(String newToken) {
        if (serviceClass != null) {
            try {
                Method sendTokenRefresh = serviceClass.getMethod("onNewToken", String.class);
                sendTokenRefresh.invoke(serviceObject, newToken);
            } catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
                Log.w(TAG, "Can't inject token due to error ", e);
            }
        }
    }

    public void injectMessage(RemoteMessage remoteMessage) {
        if (serviceClass != null) {
            try {
                Method sendTokenRefresh = serviceClass.getMethod("onMessageReceived", RemoteMessage.class);
                sendTokenRefresh.invoke(serviceObject, remoteMessage);
            } catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
                Log.w(TAG, "Can't inject message due to error ", e);
            }
        }
    }

    private void injectContext() {
        if (serviceObject != null) {
            if (setField(serviceObject, "mBase", this)) {
                Log.d(TAG, "context is set to io.flutter.plugins.firebasemessaging.FlutterFirebaseMessagingService");
            }
        }
    }

    private boolean setField(Object targetObject, String fieldName, Object fieldValue) {
        Field field;
        try {
            field = targetObject.getClass().getDeclaredField(fieldName);
        } catch (NoSuchFieldException e) {
            field = null;
        }
        Class<?> superClass = targetObject.getClass().getSuperclass();
        while (field == null && superClass != null) {
            try {
                field = superClass.getDeclaredField(fieldName);
            } catch (NoSuchFieldException e) {
                superClass = superClass.getSuperclass();
            }
        }
        if (field == null) {
            return false;
        }
        field.setAccessible(true);
        try {
            field.set(targetObject, fieldValue);
            return true;
        } catch (IllegalAccessException e) {
            return false;
        }
    }
}

编辑清单文件sdk-flutter/android/src/main/AndroidManifest.xml

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
  package="com.hypertrack.sdk.flutter">

    <application>
        <service
            android:name=".MyFirebaseMessagingService"
            android:exported="false" >
            <intent-filter android:priority="100" >
                <action android:name="com.google.firebase.MESSAGING_EVENT" />
            </intent-filter>
        </service>
    </application>
</manifest>

它是如何工作的？

MyFirebaseMessagingService 扩展自HyperTrackMessagingService，在AndroidManifest.xml 文件中声明，具有更高的优先级（绝对高于HyperTrackMessagingService）。这将允许消息直接进入新类。这也将消除方法 1 中的限制。现在我们也使用反射将消息转发到 FlutterFirebaseMessagingService。

限制：

没有限制，但需要在更新宿主库时手动更新hypertrack_plugin。 很高兴在插件本身中有这个更新，现在不存在（11 月 13 日）

方法3

现在我们不会触及库中的任何代码，而是编写我们自己的代码。我们将以安全的方式提出解决方案。您不必将 hypertrack_plugin 添加为本地依赖项。

创建类<project_root>/android/app/src/main/<your_package_name>/MyFirebaseMessagingService.java

package com.example.myapp;

import android.annotation.SuppressLint;
import android.util.Log;

import com.google.firebase.messaging.FirebaseMessagingService;
import com.google.firebase.messaging.RemoteMessage;

import org.jetbrains.annotations.NotNull;

import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

@SuppressLint("LongLogTag")
public class MyFirebaseMessagingService extends FirebaseMessagingService {

    private static final String TAG = "MyFirebaseMessagingService";

    // put all the firebase messaging service classes used in your project here
    private String[] fcmClasses = new String[]{
            "io.flutter.plugins.firebasemessaging.FlutterFirebaseMessagingService",
            "com.hypertrack.sdk.HyperTrackMessagingService"};

    @Override
    public void onNewToken(@NotNull String token) {
        Log.d(TAG, "onNewToken()");
        super.onNewToken(token);
        injectToken(token);
    }

    @Override
    public void onMessageReceived(@NotNull RemoteMessage remoteMessage) {
        Log.d(TAG, "onMessageReceived()");
        super.onMessageReceived(remoteMessage);
        injectMessage(remoteMessage);
    }

    public void injectToken(String newToken) {
        Log.d(TAG, "injectToken()");

        for (String fcmClass : fcmClasses) {
            try {
                Class<?> serviceClass = Class.forName(fcmClass);
                Object serviceObject = serviceClass.newInstance();
                injectContext(serviceClass, serviceObject);

                Method sendTokenRefresh = serviceClass.getMethod("onNewToken", String.class);
                sendTokenRefresh.invoke(serviceObject, newToken);

            } catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException | ClassNotFoundException | InstantiationException e) {
                Log.w(TAG, "Can't inject token due to error ", e);
            }
        }
    }

    public void injectMessage(RemoteMessage remoteMessage) {
        Log.d(TAG, "injectMessage()");

        for (String fcmClass : fcmClasses) {
            try {
                Class<?> serviceClass = Class.forName(fcmClass);
                Object serviceObject = serviceClass.newInstance();
                injectContext(serviceClass, serviceObject);

                Method sendTokenRefresh = serviceClass.getMethod("onMessageReceived", RemoteMessage.class);
                sendTokenRefresh.invoke(serviceObject, remoteMessage);
            } catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException | ClassNotFoundException | InstantiationException e) {
                Log.w(TAG, "Can't inject token due to error ", e);
            }
        }
    }

    private void injectContext(Class<?> serviceClass, Object serviceObject) {
        Log.d(TAG, "injectContext()");
        if (serviceClass != null) {
            if (setField(serviceObject, "mBase", this)) {
                Log.d(TAG, "context is set to " + serviceClass.getName());
            }
        }
    }

    private boolean setField(Object targetObject, String fieldName, Object fieldValue) {
        Log.d(TAG, "setField()");

        Field field;
        try {
            field = targetObject.getClass().getDeclaredField(fieldName);
        } catch (NoSuchFieldException e) {
            field = null;
        }
        Class<?> superClass = targetObject.getClass().getSuperclass();
        while (field == null && superClass != null) {
            try {
                field = superClass.getDeclaredField(fieldName);
            } catch (NoSuchFieldException e) {
                superClass = superClass.getSuperclass();
            }
        }
        if (field == null) {
            return false;
        }
        field.setAccessible(true);
        try {
            field.set(targetObject, fieldValue);
            return true;
        } catch (IllegalAccessException e) {
            return false;
        }
    }
}

在<project_root>/couriers/android/app/src/main/AndroidManifest.xml中声明

重要提示：设置优先级高于 5（在 HyperTrack SDK 中声明）

     <service
            android:name=".MyFirebaseMessagingService"
            android:exported="false">
            <intent-filter android:priority="100">
                <action android:name="com.google.firebase.MESSAGING_EVENT" />
            </intent-filter>
        </service>

它是如何工作的？

我们明确地创建了MyFirebaseMessagingService 并从FirebaseMessagingService 扩展。我们还设置了高达 100 的优先级，以确保我们仅在此处接收传入消息，而不是在任何其他 Firebase 消息传递服务（如 HyperTrack）中接收。现在我们可以灵活地使用反射将这条消息转发到任何需要的地方。

限制：

无

【讨论】：