java - 当我使用 Google Cloud Messaging 时，无法解析方法 addOnCompleteListener

Question

我尝试使用 Firebase Cloud Messaging，但遇到了一些问题。我编写了订阅主题的代码，但是当我在 addOnCompleteListener 中使用时，出现此错误:

Cannot resolve method 'addOnCompleteListener(live.jtube.app.MassegeNetsActivity, anonymous com.google.android.gms.tasks.OnCompleteListener)'

这是我的代码的一部分:

MassegeNetsActivity.java代码:

 .....
 import com.google.android.gms.tasks.OnCompleteListener;
 import com.google.android.gms.tasks.Task;
 import com.google.firebase.messaging.FirebaseMessaging;
 import android.content.BroadcastReceiver;
 import android.content.IntentFilter;
 ..... 

 protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.massege_nets);

  FirebaseMessaging.getInstance().subscribeToTopic("weather")
          .addOnCompleteListener(MassegeNetsActivity.this, new OnCompleteListener<Void>() { //here i got the error
                @Override
                public void onComplete(@NonNull Task<Void> task) {
                    String msg = "תהליך הרשמה לערוץ בוצע בהצלחה!";
                    if (!task.isSuccessful()) {
                        msg = "אופס! תהליך הרישום לערוץ נכשל, אנא בדוק את החיבור שלך לאינטרנט";
                    }
                   // Log.d(TAG, msg);
                    Toast.makeText(getApplicationContext(), msg, Toast.LENGTH_SHORT).show();
                }
            });
      ......

这里是 build.gradle 文件:

apply plugin: 'com.android.application'
apply plugin: 'com.google.gms.google-services'

android {
    compileSdkVersion 28
    buildToolsVersion "28.0.2"
    defaultConfig {
        applicationId "app.app.app"
        minSdkVersion 15
        targetSdkVersion 28
        versionCode 34
        versionName "4.17"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
        vectorDrawables.useSupportLibrary = true
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    compile 'com.android.support.constraint:constraint-layout:1.1.3'
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })

    //firebase
    //firebase analytics
    // compile 'com.google.firebase:firebase-messaging:12.0.1'//firebase Cloud Messaging
    compile 'com.android.support:appcompat-v7:28.0.0'
    compile 'com.android.support:design:28.0.0'
    compile 'com.android.support:support-vector-drawable:28.0.0'
    compile 'com.google.firebase:firebase-core:16.0.1'
    compile 'com.google.firebase:firebase-messaging:12.0.1'
    compile 'com.google.firebase:firebase-ads:12.0.1'
    compile 'com.google.firebase:firebase-analytics:15.0.0'
    compile 'com.google.firebase:firebase-auth:15.0.0'

    //implementation 'com.google.firebase:firebase-analytics:12.0.1'
    compile 'com.android.support:support-v4:28.0.0'
    compile "com.android.support:support-compat:28.0.0"
    compile 'com.android.support:support-media-compat:28.0.0'

    testCompile 'junit:junit:4.12'
}

我在谷歌上搜索了近 3 个小时，但找不到任何有效的答案......

你能帮我吗？

非常感谢!

Answer 1

您在评论中链接的示例仅传递一个 OnCompleteListener，而您的代码则传递一个额外的 MassegeNetsActivity.this 作为之前的参数。虽然有一个带有两个参数的 addOnCompleteListener ，但在该重载中，第一个参数是 Executor ，而 Activity 实例似乎不是一个有效的Executor对象。

解决方案是仅使用监听器调用 addOnCompleteListener:

FirebaseMessaging.getInstance().subscribeToTopic("weather")
          .addOnCompleteListener(new OnCompleteListener<Void>() {
    ...