确保先调用 FirebaseApp.initializeApp(Context) [英] Make sure to call FirebaseApp.initializeApp(Context) first
问题描述
其他问题可能已经完全相同，但我真的不知道这里出了什么问题.预先感谢您的帮助.
It might be really same with other questions already but I don't really know what's wrong in here. Thanks in advance for the help.
build.gradle(项目)
build.gradle (project)
// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {
repositories {
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:2.3.3'
classpath 'com.google.gms:google-services:3.1.0'
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
allprojects {
repositories {
jcenter()
maven {
url "https://maven.google.com" // Google's Maven repository
}
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}
build.gradle(module)
build.gradle(module)
apply plugin: 'com.android.application'
android {
compileSdkVersion 25
buildToolsVersion "25.0.3"
defaultConfig {
applicationId "com.bustracker.usc.myapplication"
minSdkVersion 21
targetSdkVersion 25
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(include: ['*.jar'], dir: 'libs')
androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
exclude group: 'com.android.support', module: 'support-annotations'
})
compile 'com.android.support:appcompat-v7:25.3.1'
compile 'com.android.support.constraint:constraint-layout:1.0.0-alpha7'
compile 'com.google.android.gms:play-services-maps:10.2.6'
compile 'com.google.android.gms:play-services-location:10.2.6'
compile 'com.google.firebase:firebase-database:10.2.6'
testCompile 'junit:junit:4.12'
}
apply plugin: 'com.google.gms.google-services'
MainActivity.java
MainActivity.java
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
FirebaseApp.initializeApp(this);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.activity_main);
firebaseDatabase = FirebaseDatabase.getInstance();
mRootReference = firebaseDatabase.getReference();
mheadingReference = mRootReference.child("users");
错误:
FATAL EXCEPTION: main
Process: com.bustracker.sample.myapplication, PID: 2658
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.bustracker.sample.myapplication/com.bustracker.sample.myapplication.MainActivity}: java.lang.IllegalStateException: Default FirebaseApp is not initialized in this process com.bustracker.sample.myapplication. Make sure to call FirebaseApp.initializeApp(Context) first.
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2665)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6119)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
Caused by: java.lang.IllegalStateException: Default FirebaseApp is not initialized in this process com.bustracker.sample.myapplication. Make sure to call FirebaseApp.initializeApp(Context) first.
at com.google.firebase.FirebaseApp.getInstance(Unknown Source)
at com.google.firebase.database.FirebaseDatabase.getInstance(Unknown Source)
at com.bustracker.sample.myapplication.MainActivity.onCreate(MainActivity.java:53)
at android.app.Activity.performCreate(Activity.java:6679)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2618)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6119)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
其他问题可能已经完全相同，但我真的不知道这里出了什么问题.预先感谢您的帮助.
It might be really same with other questions already but I don't really know what's wrong in here. Thanks in advance for the help.
推荐答案
根据文档:
如文档中所述:
任何 FirebaseApp 初始化都只能在应用的主进程中进行.不支持在主进程以外的进程中使用 Firebase，这可能会导致与资源争用相关的问题.
Any FirebaseApp initialization must occur only in the main process of the app. Use of Firebase in processes other than the main process is not supported and will likely cause problems related to resource contention.
你需要在活动中初始化它.
you need to initialize it not in the activity.
向清单示例中添加应用程序类:
add an application class to your manifest example:
<applicaton
android:name="MyApplication"
然后这样做:
public class MyApplication extends Application {
@Override
public void onCreate() {
super.onCreate();
FirebaseApp.initializeApp(this);
}
并从活动中删除初始化.您需要在作为基类的应用程序类中对其进行初始化.
and remove the initialization from the activity. You need to initialize it in the application class which is the base class.
编辑(关于申请):
用于维护全局应用程序状态的基类.您可以通过创建一个子类并将该子类的完全限定名称指定为android:name"来提供您自己的实现.AndroidManifest.xml 标签中的属性.在为您的应用程序/包创建进程时，Application 类或您的 Application 类的子类在任何其他类之前被实例化.
Base class for maintaining global application state. You can provide your own implementation by creating a subclass and specifying the fully-qualified name of this subclass as the "android:name" attribute in your AndroidManifest.xml's tag. The Application class, or your subclass of the Application class, is instantiated before any other class when the process for your application/package is created.
有用链接:https://developer.android.com/reference/android/app/Application.html
这篇关于确保先调用 FirebaseApp.initializeApp(Context)的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
