&引用；FCM"；应用程序在此行getToken（）上崩溃；java.lang.IllegalStateException:默认FirebaseApp在此过程中未初始化； FCM（Firebase云消息传递）初始化问题_Java_Android_Firebase_Android Studio_Android Developer Api

&引用；FCM"；应用程序在此行getToken（）上崩溃；java.lang.IllegalStateException:默认FirebaseApp在此过程中未初始化； FCM（Firebase云消息传递）初始化问题

java android firebase android-studio

&引用；FCM"；应用程序在此行getToken（）上崩溃；java.lang.IllegalStateException:默认FirebaseApp在此过程中未初始化； FCM（Firebase云消息传递）初始化问题,java,android,firebase,android-studio,android-developer-api,Java,Android,Firebase,Android Studio,Android Developer Api,我开始研究FCM模块，我按照firebase指南休学。我得到了两个异常，比如RuntimeException和IllegalStateException。Firebase init默认设置，但FCM中的问题是什么以及原因 1.从Android Studio工具->Firebase->云消息。 2.我建立了火基云台。我放弃了以下链接：应用程序：Build.gradle dependencies { implementation fileTree(dir: 'libs', includ

我开始研究FCM模块，我按照firebase指南休学。我得到了两个异常，比如RuntimeException和IllegalStateException。Firebase init默认设置，但FCM中的问题是什么以及原因

1.从Android Studio工具->Firebase->云消息。 2.我建立了火基云台。我放弃了以下链接：

应用程序：Build.gradle

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    //noinspection GradleCompatible
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    implementation 'com.google.firebase:firebase-messaging:17.4.0'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}

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

buildscript {
    repositories {
        google()
        jcenter()
        
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.3.2'
        classpath 'com.google.gms:google-services:4.1.0'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        google()
        jcenter()
        
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

buildscript {
    repositories {
        mavenLocal()  //This is the line you need to add 
        google()
        jcenter()

    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.3.2'
        classpath 'com.google.gms:google-services:4.2.0'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        mavenLocal() //This is the line you need to add 
        google()
        jcenter()

    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

apply plugin: 'com.android.application'


android {
    compileSdkVersion 28
    defaultConfig {
        applicationId "com.example.testfcm"
        minSdkVersion 21
        targetSdkVersion 28
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    //noinspection GradleCompatible
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'


    implementation 'com.google.firebase:firebase-core:16.0.8'
    implementation 'com.google.firebase:firebase-iid:17.1.1'
    implementation 'com.google.firebase:firebase-messaging:17.5.0'

    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}
apply plugin: 'com.google.gms.google-services'

项目：Build.gradle

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    //noinspection GradleCompatible
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    implementation 'com.google.firebase:firebase-messaging:17.4.0'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}

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

buildscript {
    repositories {
        google()
        jcenter()
        
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.3.2'
        classpath 'com.google.gms:google-services:4.1.0'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        google()
        jcenter()
        
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

buildscript {
    repositories {
        mavenLocal()  //This is the line you need to add 
        google()
        jcenter()

    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.3.2'
        classpath 'com.google.gms:google-services:4.2.0'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        mavenLocal() //This is the line you need to add 
        google()
        jcenter()

    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

apply plugin: 'com.android.application'


android {
    compileSdkVersion 28
    defaultConfig {
        applicationId "com.example.testfcm"
        minSdkVersion 21
        targetSdkVersion 28
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    //noinspection GradleCompatible
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'


    implementation 'com.google.firebase:firebase-core:16.0.8'
    implementation 'com.google.firebase:firebase-iid:17.1.1'
    implementation 'com.google.firebase:firebase-messaging:17.5.0'

    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}
apply plugin: 'com.google.gms.google-services'

在MainActivity.class中，我试图获取令牌，但应用程序崩溃

 public class MainActivity extends AppCompatActivity {

    public static final String TAG = MainActivity.class.getSimpleName();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        String tokenId = FirebaseInstanceId.getInstance().getToken(); //Crashes in this line 
        Log.d("SH", tokenId);
    }
}

在logcat中，我有两个例外

 E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.package PID: 29368
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.package.testfcm/com.package.MainActivity}: java.lang.IllegalStateException: Default FirebaseApp is not initialized in this process com.package. Make sure to call FirebaseApp.initializeApp(Context) first.
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2861)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2943)
        at android.app.ActivityThread.-wrap11(Unknown Source:0)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1630)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:164)
        at android.app.ActivityThread.main(ActivityThread.java:6626)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:811)
     Caused by: java.lang.IllegalStateException: Default FirebaseApp is not initialized in this process com.package. Make sure to call FirebaseApp.initializeApp(Context) first.
        at com.google.firebase.FirebaseApp.getInstance(com.google.firebase:firebase-common@@16.0.2:240)
        at com.google.firebase.iid.FirebaseInstanceId.getInstance(Unknown Source:1)
        at com.package.MainActivity.onCreate(MainActivity.java:20)
        at android.app.Activity.performCreate(Activity.java:7032)
        at android.app.Activity.performCreate(Activity.java:7023)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1236)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2814)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2943) 
        at android.app.ActivityThread.-wrap11(Unknown Source:0) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1630) 
        at android.os.Handler.dispatchMessage(Handler.java:106) 
        at android.os.Looper.loop(Looper.java:164) 
        at android.app.ActivityThread.main(ActivityThread.java:6626) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:811)

最后我找到了解决方案，现在我可以得到FCM代币了

在project build.gradle文件中，您需要添加单行代码，即mavenLocal（）。根据以下解决方案休耕交叉检查项目：build.gradle文件和app:build.gradle文件

项目：build.gradle

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    //noinspection GradleCompatible
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    implementation 'com.google.firebase:firebase-messaging:17.4.0'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}

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

buildscript {
    repositories {
        google()
        jcenter()
        
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.3.2'
        classpath 'com.google.gms:google-services:4.1.0'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        google()
        jcenter()
        
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

buildscript {
    repositories {
        mavenLocal()  //This is the line you need to add 
        google()
        jcenter()

    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.3.2'
        classpath 'com.google.gms:google-services:4.2.0'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        mavenLocal() //This is the line you need to add 
        google()
        jcenter()

    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

apply plugin: 'com.android.application'


android {
    compileSdkVersion 28
    defaultConfig {
        applicationId "com.example.testfcm"
        minSdkVersion 21
        targetSdkVersion 28
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    //noinspection GradleCompatible
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'


    implementation 'com.google.firebase:firebase-core:16.0.8'
    implementation 'com.google.firebase:firebase-iid:17.1.1'
    implementation 'com.google.firebase:firebase-messaging:17.5.0'

    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}
apply plugin: 'com.google.gms.google-services'

应用程序：build.gradle

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    //noinspection GradleCompatible
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    implementation 'com.google.firebase:firebase-messaging:17.4.0'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}

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

buildscript {
    repositories {
        google()
        jcenter()
        
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.3.2'
        classpath 'com.google.gms:google-services:4.1.0'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        google()
        jcenter()
        
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

buildscript {
    repositories {
        mavenLocal()  //This is the line you need to add 
        google()
        jcenter()

    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.3.2'
        classpath 'com.google.gms:google-services:4.2.0'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        mavenLocal() //This is the line you need to add 
        google()
        jcenter()

    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

apply plugin: 'com.android.application'


android {
    compileSdkVersion 28
    defaultConfig {
        applicationId "com.example.testfcm"
        minSdkVersion 21
        targetSdkVersion 28
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    //noinspection GradleCompatible
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'


    implementation 'com.google.firebase:firebase-core:16.0.8'
    implementation 'com.google.firebase:firebase-iid:17.1.1'
    implementation 'com.google.firebase:firebase-messaging:17.5.0'

    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}
apply plugin: 'com.google.gms.google-services'

我可以从您的代码中看出，您在初始化Firebase实例之前就已经得到了它。您必须首先初始化它，然后使用

getInstance（）

获取令牌

或者尝试谷歌文档显示的获取令牌的方式

FirebaseInstanceId.getInstance().getInstanceId()
        .addOnCompleteListener(new OnCompleteListener<InstanceIdResult>() {
            @Override
            public void onComplete(@NonNull Task<InstanceIdResult> task) {
                if (!task.isSuccessful()) {
                    Log.w(TAG, "getInstanceId failed", task.getException());
                    return;
                }

                // Get new Instance ID token
                String token = task.getResult().getToken();


                Toast.makeText(MainActivity.this, token, Toast.LENGTH_SHORT).show();
            }
        });

FirebaseInstanceId.getInstance（）.getInstanceId（）
.addOnCompleteListener（新的OnCompleteListener（）{
@凌驾
未完成的公共void（@NonNull任务）{
如果（！task.issusccessful（））{
w（标记“getInstanceId失败”，task.getException（））；
返回；
}
//获取新实例ID令牌
字符串标记=task.getResult（）.getToken（）；
Toast.makeText（MainActivity.this，Toast.LENGTH_SHORT.show（）；
}
});

试试这种方法。

在Android Studio中，进入工具菜单。
然后选择Firebase选项。
提供启用firebase的google帐户id密码。
从右侧选项卡中选择云消息。
然后单击设置firebase消息。

按照那边的标注步骤进行操作。

确保您已在应用程序中添加了google json文件，并用软件包名称检查文件中的软件包名称。最后添加FirebaseApp.initializeApp（this）；在activityYes中，我添加了google json文件。Firebase需要时间连接到it服务器，并为您提供设备引用的实例，给它一些时间或使用承诺确保Firebase连接到it服务器并生成实例，然后执行需要Firebase实例的操作。最后，我找到了解决方案。只需在project build.gradle文件中添加单行代码，即mavenLocal（）；检查更新的答案是的，我检查了上面的答案，仍然得到相同的异常和相同的崩溃。