在Android 11中,由于锁屏限制了应用程序的后台活动,因此可能会出现FCM消息在锁屏状态下无法传递到应用程序的情况。为了解决这个问题,可以使用一些方法来确保可以在锁屏状态下接收到FCM消息。
一种方法是使用NotificationListenerService。以下是一个示例代码:
首先,在Manifest文件中注册Service:
然后,在MyNotificationListenerService类中重写onNotificationPosted方法,并在其中处理FCM消息:
import android.service.notification.NotificationListenerService
import android.service.notification.StatusBarNotification
import com.google.firebase.messaging.FirebaseMessagingService
import com.google.firebase.messaging.RemoteMessage
class MyNotificationListenerService : NotificationListenerService() {
override fun onNotificationPosted(sbn: StatusBarNotification?) {
super.onNotificationPosted(sbn)
// Check if the notification is from FCM
if (sbn?.packageName == "com.google.android.gms" &&
sbn.notification?.extras?.getString("google.sent_time") != null &&
sbn.notification?.extras?.getString("google.message_id") != null) {
// Get the FCM message
val message = RemoteMessage(sbn.notification?.extras)
// Handle the FCM message
// ...
}
}
}
通过这种方法,即使在锁屏状态下,也可以接收到FCM消息并在自定义的NotificationListenerService类中处理它们。
还可以在MyFirebaseMessagingService类中处理FCM消息,并在onMessageReceived函数中添加以下代码:
override fun onMessageReceived(remoteMessage: RemoteMessage) {
super.onMessageReceived(remoteMessage)
// Check if the app is in the foreground
if (isAppInForeground()) {
// Handle the FCM message
// ...
}
else {
// Show the notification
val notification = NotificationHelper.createNotification(this, remoteMessage.notification?.title, remoteMessage.notification?.body)
NotificationHelper.notify(this, notification)
}
}
private fun isAppInForeground(): Boolean {
val activityManager = getSystemService(Context.ACTIVITY_SERVICE) as ActivityManager
val appProcesses = activityManager.runningAppProcesses
if (appProcesses != null) {
for (appProcess in appProcesses)