确保首先在Android中调用FirebaseApp.initializeApp(Context) [英] Make sure to call FirebaseApp.initializeApp(Context) first in Android
问题描述
我正面临这个问题，并在此站点上看到了一些答案，但没有得到任何适当的解决方案.
我使用了Firebase的早期版本，该版本可以正常工作，但是当我尝试使用升级并将Firebase类更新为DatabaseReference，它显示错误且不起作用.
我正在添加清单文件的完整代码，因此请帮助我解决此问题.
这是我的manifest
I am facing this issue and seen some answers on this site but did not get any proper solution.
I have used previous version of Firebase which works fine but when I try to upgrade using Upgradation and update Firebase class to DatabaseReference it shows error and not working.
I am adding my manifest file entire code so please help me to resolve this issue.
Here is my manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="firebasechat.com.firebasechat">
<uses-permission android:name="android.permission.INTERNET" />
<application
android:allowBackup="true"
android:name=".Activity.SimpleBlog"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".Activity.RegisterActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
我的Module app在下面给出.
apply plugin: 'com.android.application'
android {
compileSdkVersion 26
buildToolsVersion "26.0.0"
defaultConfig {
applicationId "firebasechat.com.firebasechat"
minSdkVersion 15
targetSdkVersion 26
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
multiDexEnabled true
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
packagingOptions {
exclude 'META-INF/LICENSE'
exclude 'META-INF/LICENSE-FIREBASE.txt'
exclude 'META-INF/NOTICE'
}
}
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-v7:26.+'
compile 'com.android.volley:volley:1.0.0'
compile "com.google.firebase:firebase-database:11.0.0"
compile 'com.google.android.gms:play-services:11.0.0'
compile 'com.android.support:recyclerview-v7:25.0.0'
testCompile 'junit:junit:4.12'
testCompile 'junit:junit:4.12'
}
和Project gradle
// 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:4.2.0'// Updated version of google service
}
}
allprojects {
repositories {
jcenter()
maven {
url "https://maven.google.com" // Google's Maven repository
}
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}
下面是我的Activity.
public class RegisterActivity extends AppCompatActivity {
EditText username, password;
Button registerButton;
String user, pass;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
username = (EditText)findViewById(R.id.username);
password = (EditText)findViewById(R.id.password);
registerButton = (Button)findViewById(R.id.registerButton);
FirebaseApp.initializeApp(this);
registerButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
user = username.getText().toString();
pass = password.getText().toString();
final ProgressDialog pd = new ProgressDialog(RegisterActivity.this);
pd.setMessage("Loading...");
pd.show();
String url = "https://pure-coda-174710.firebaseio.com/users.json";
StringRequest request = new StringRequest(Request.Method.GET, url, new Response.Listener<String>(){
@Override
public void onResponse(String s) {
// Firebase reference = new Firebase("https://pure-coda-174710.firebaseio.com/users");
DatabaseReference reference = FirebaseDatabase.getInstance()
.getReferenceFromUrl("https://pure-coda-174710.firebaseio.com/users");
if(s.equals("null")) {
reference.child(user).child("password").setValue(pass);
Toast.makeText(RegisterActivity.this, "registration successful", Toast.LENGTH_LONG).show();
}
else {
try {
JSONObject obj = new JSONObject(s);
if (!obj.has(user)) {
reference.child(user).child("password").setValue(pass);
Toast.makeText(RegisterActivity.this, "registration successful", Toast.LENGTH_LONG).show();
} else {
Toast.makeText(RegisterActivity.this, "username already exists", Toast.LENGTH_LONG).show();
}
} catch (JSONException e) {
e.printStackTrace();
}
}
pd.dismiss();
}
},new Response.ErrorListener(){
@Override
public void onErrorResponse(VolleyError volleyError) {
System.out.println("" + volleyError );
pd.dismiss();
}
});
RequestQueue rQueue = Volley.newRequestQueue(RegisterActivity.this);
rQueue.add(request);
}
});
}
}
推荐答案
在您的SimpleBlog应用程序类中，使用onCreate()方法初始化FirebaseApp并将其从RegisterActivity中删除，以使Firebase初始化为 entire 应用程序，而不仅仅是一个Activity.
In your SimpleBlog application class, initialize FirebaseApp in onCreate() method and remove it from RegisterActivity in order to have Firebase initialize into entire application, not just one Activity.
@Override
public void onCreate() {
super.onCreate();
FirebaseApp.initializeApp(this);
}
还要在应用gradle的末尾添加apply plugin: 'com.google.gms.google-services':
Also add apply plugin: 'com.google.gms.google-services' at the end of app gradle:
dependencies {
....
}
apply plugin: 'com.google.gms.google-services'
需要插件才能从firebase处理您的json配置，并避免依赖冲突.您可以阅读此处以了解更多详细信息.
Plugin is required to process your json config from firebase and to avoid dependency collisions. You can read here for more details.
这篇关于确保首先在Android中调用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！
