问题描述
我想通过Firebase发送和接收远程通知,但是我的自定义类找不到getApplicationContext()
方法.
I want to send and receive remote notification through Firebase but my custom class could not find getApplicationContext()
method.
据我了解,FirebaseMessagingService扩展了Service , which extends
ContextWrapper`,后者扩展了Context.
From my understanding, FirebaseMessagingService extends Service, which extends
ContextWrapper` which extends Context.
所以我不知道getApplicationContext()
无法正常工作.任何帮助将不胜感激!
So I don't know getApplicationContext()
is not working. Any help will be appreciated!
import com.google.firebase.messaging.FirebaseMessagingService;
import com.google.firebase.messaging.RemoteMessage;
public class FirebaseMessageService extends FirebaseMessagingService {
@Override
public void onMessageReceived(RemoteMessage remoteMessage) {
if(remoteMessage.getNotification() != null){
String title = remoteMessage.getNotification().getTitle();
String text = remoteMessage.getNotification().getBody();
NotificationHelper.displayNotification(getApplicationContext(), title, text);
}
super.onMessageReceived(remoteMessage);
}
}
这是我的AndroidManifest.xml文件.
Here's my AndroidManifest.xml file.
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.mealz">
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme.NoActionBar">
<activity android:name=".Activities.UserActivity"></activity>
<activity android:name=".Activities.LoginActivity" />
<activity android:name=".Activities.SignupActivity" />
<activity android:name=".Activities.SearchRecipeActivity" />
<activity android:name=".Activities.RecipeDetailActivity" />
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<service android:name=".Notifications.FirebaseMessageService">
<intent-filter>
<action android:name="com.google.firebase.MESSAGING_EVENT" />
</intent-filter>
</service>
</application>
</manifest>
推荐答案
您可以通过多种方式实现此目的,一种方法是保持上下文的弱引用,使应用程序类扩展android.app.application并在其上创建方法并创建一个上下文弱引用的变量并将其分配给getApplicationContext(),您可以在所需的任何位置使用此上下文.
You can achieve this in many way one way is to keep a weak refrence of context make a app class extending android.app.application and on it's create method and make a variable of weak refrence of context and assign it to getApplicationContext() and you may use this context anywhere you want.
public class app extends android.app.Application{
private static WeakReference<Context> referenceCntx;
@Override
public void onCreate() {
super.onCreate();
referenceCntx = new WeakReference<>(getApplicationContext());
}
public static Context getApplicationCntx(){
return referenceCntx.get();
}
}
别忘了在清单中添加此行
And don't forget to add this line in manifest
<application
android:name=".app"
这篇关于在从FirebaseMessagingService扩展的类中找不到getApplicationContext()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!