Question

我正在尝试在Android应用中设置Firebase消息传递，据我了解，在对Firebase类进行任何其他操作之前，我需要运行FirebaseApp.initializeApp(context)。我遇到的问题是我在尝试使用initializeApp获取设备令牌之前正在运行FirebaseInstanceId.getInstance().getInstanceId()，但是firebase仍然会抛出此错误：

09-05 11:16:20.314 24640-24640/com.company.AppName E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.company.AppName, PID: 24640
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.company.AppName/com.company.AppName.MainActivity}: java.lang.IllegalStateException: Default FirebaseApp is not initialized in this process com.company.AppName. Make sure to call FirebaseApp.initializeApp(Context) first.
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2778)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)
        at android.app.ActivityThread.-wrap11(Unknown Source:0)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:164)
        at android.app.ActivityThread.main(ActivityThread.java:6494)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
     Caused by: java.lang.IllegalStateException: Default FirebaseApp is not initialized in this process com.company.AppName. Make sure to call FirebaseApp.initializeApp(Context) first.
        at com.google.firebase.FirebaseApp.getInstance(com.google.firebase:firebase-common@@16.0.1:219)
        at com.google.firebase.iid.FirebaseInstanceId.getInstance(Unknown Source:1)
        at com.company.AppName.MainActivity.onCreate(MainActivity.java:48)
        at android.app.Activity.performCreate(Activity.java:7009)
        at android.app.Activity.performCreate(Activity.java:7000)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1214)

这是初始化firebase并引发错误的代码（在MainActivity.java onCreate中）：

FirebaseApp.initializeApp(this);
NativeApp
    .shared()
    .setContext(this)
    .setDeviceToken(FirebaseInstanceId.getInstance().getInstanceId().toString());

如果我注释掉setDeviceToken行，则不会引发任何错误。 initializeApp是异步的吗？ Firebase Android setup guide设法不提initializeApp。

Answer 1

如果您使用documented procedure与Firebase进行了集成，则无需调用initializeApp。如果您进行标准集成，则Firebase将在应用启动时自动初始化。请在API docs for FirebaseApp中阅读有关此内容的更多信息。

如果您不执行标准集成，则取决于您的用例，在合适的时间调用initializeApp。

Firebase尽管已初始化但仍引发未初始化错误

1 个答案: