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，并在本网站上看到了一些答案，但没有得到任何适当的解决方案.
我使用了以前版本的 Firebase，它工作正常，但是当我尝试使用 升级 并将 Firebase 类更新为 DatabaseReference 它显示错误并且不工作.
我正在添加我的清单文件的整个代码，所以请帮助我解决这个问题.
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>
我的模块应用如下.
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'
}
和项目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，在 onCreate() 方法中初始化 FirebaseApp 并将其从 中删除>RegisterActivity 以便让 Firebase 初始化到整个应用程序，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);
}
同时在 app 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'
需要插件来处理来自 firebase 的 json 配置并避免依赖冲突.您可以阅读此处了解更多详情.
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！
