问题描述
其他问题可能已经完全相同，但是我真的不知道这里有什么问题.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(模块)
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，但是我真的不知道这里有什么问题.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:
任何FirebaseApp初始化必须仅在应用程序的主要过程中发生.不支持在主流程以外的其他流程中使用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.
您无需在活动中初始化它.
you need to initialize it not in the activity.
将应用程序类添加到清单示例中
add an application class to your manifest example:
<applicaton
android:name="MyApplication"
然后执行以下操作:
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(关于应用程序):
Edit(about application):
有用的链接: https://developer.android.com/reference/android/app/Application.html
这篇关于确保首先调用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！