在onMessageReceived - FCM中显示警报对话框

Question

我试图在onMessageReceived类的MyFirebaseMessagingService中显示一条警告消息，我收到一个错误消息：

    java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
                                                                                    at android.os.Handler.<init>(Handler.java:200)
                                                                                    at android.os.Handler.<init>(Handler.java:114)
                                                                                    at android.app.Activity.<init>(Activity.java:846)
                                                                                    at android.support.v4.app.SupportActivity.<init>(SupportActivity.java:38)
                                                                                    at android.support.v4.app.BaseFragmentActivityApi14.<init>(BaseFragmentActivityApi14.java:28)
                                                                                    at android.support.v4.app.BaseFragmentActivityApi16.<init>(BaseFragmentActivityApi16.java:34)
                                                                                    at android.support.v4.app.FragmentActivity.<init>(FragmentActivity.java:67)
                                                                                    at android.support.v7.app.AppCompatActivity.<init>(AppCompatActivity.java:61)
                                                                                    at com.dopay.onboarding.activity.BaseActivity.<init>(BaseActivity.java:51)
                                                                                    at com.dopay.onboarding.FMS.MyFirebaseMessagingService.onMessageReceived(MyFirebaseMessagingService.java:75)
                                                                                    at com.google.firebase.messaging.FirebaseMessagingService.handleIntent(Unknown Source)
                                                                                    at com.google.firebase.iid.zzc.run(Unknown Source)
                                                                                    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
                                                                                    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
                                                                                    at java.lang.Thread.run(Thread.java:762)
02

我试过了什么

@Override
    public void onMessageReceived(RemoteMessage remoteMessage) {

        if (remoteMessage.getData().size() > 0) {
 BaseActivity baseActivity = new BaseActivity();
                baseActivity.showDialog();
}

}

BaseActivity

  public void showDialog(){
        this.runOnUiThread(new Runnable() {
            public void run() {
                    //Toast.makeText(this, "Hello", Toast.LENGTH_SHORT).show();
                DialogUtil.showAlert(getApplicationContext(), R.string.message_complete_required_fields);
            }
        });
    }

对话框的Util

  public static void showAlert(Context context, int messageId) {
        AlertDialog.Builder builder = new AlertDialog.Builder(context);
        builder.setMessage(messageId)
                .setCancelable(true)
                .setPositiveButton(context.getResources().getString(R.string.label_ok), null);
        builder.create().show();
    }

有关如何在onMessageReceived中打开警报对话框的任何建议。

谢谢R

Answer 1

这是我的问题的两分钱：

1. 使用Activity上下文来显示对话框或任何与UI相关的内容。你开始活动的方式也不是它的开放方式。您可以选择在顶部栏上显示通知并在其上设置PendingIntent，以便单击它可以打开所需的活动。 Open specific Activity when notification clicked in FCM
2. 而不是从BaseActivity获得onMessageReceived的引用，让它们分离。使用LocalBroadcastManager或Handler向Activity发送消息以显示对话框。这样，如果活动打开，它将对其采取行动，否则它将不会做任何事情。检查GCM IntentService how to display a pop up on notification receive

Answer 2

问题是这一行：BaseActivity baseActivity = new BaseActivity（）;您不应该创建Activity的实例，它应该由系统通过Intent创建。当您通过“new”命令创建实例时，它被视为普通类，并且所有上下文都将是错误的。

我们的想法是启动一个活动，让活动处理对话。快速解决方法是这样的：

@Override public void onMessageReceived（RemoteMessage remoteMessage）{

    if (remoteMessage.getData().size() > 0) {
         Intent intent = new Intent(this, BaseActivity.class);
         startActivity(intent);
    }

}

在BaseActivity.class上，在onCreate（）方法中调用showDialog（）。