如何向 MainActivity 发送 FCM 消息

Question

我想在我的 mainActivity 中显示 FCM 收到的消息作为 bottomNavigation 徽章， 但是如何从服务向 activity 发送数据？ 我用过：

override fun onMessageReceived(p0: RemoteMessage) {
    super.onMessageReceived(p0)

        val intent = Intent(this, MainActivity::class.java)
        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
        intent.putExtra("badge", p0.notification?.body)
        startActivity(intent)
    }

但是这段代码打开了一个新的 MainActivity，同时还有另一个 MainActivity！

Answer 1

如果您的服务和 activity 运行 在同一进程中，您可以尝试发送 LocalBroadcast。

// Inside the service
override fun onMessageReceived(p0: RemoteMessage) {
    super.onMessageReceived(p0)
    val lbm = LocalBroadcastManager.getInstance(this)
    val dataIntent = Intent().apply { 
        putExtra("badge", p0.notification?.body) 
    }
    lbm.sendBroadcast(dataIntent)
}

// Inside the activity
private val lbm by lazy { LocalBroadcastManager.getInstance(this) }
private val badgeListener = object : BroadcastReceiver() {
    override fun onReceive(ctx: Context, data: Intent) {        
         val count = intent.getIntExtra("badge")
         // Update the view here
    }
}


override fun onCreate(){
    // Other stuff
    lbm.registerReceiver(badgeListener)
}

override fun onDestroy() {
    lbm.unregisterReceiver(badgeListener)
}