android - 服务的 Intent.replaceExtras(bundle) 未按预期工作

Question

我有一个服务，对于本次讨论，它包含一个数字和一个字符串以呈现给 Activity 。将其视为面向服务的复制缓冲区。启动后，服务将像这样启动(使用 startService):

Intent srvIntent = new Intent(this, SetManager.class);
Bundle bundle = new Bundle();
bundle.putLong(getString(R.string.intent_key_setnbr), setNbr);
bundle.putString(getString(R.string.intent_key_setmsg), setMsg);
srvIntent.putExtras(bundle);
startService(srvIntent);
return true;

一切正常。服务启动，在通知中显示由 setMsg 标识的消息(例如“MESSAGE1”)。

当用户触摸 Notification 时，将启动一个 Activity，该 Activity 会更新 setNbr 和 setMsg，并将它们发送回服务。该服务反过来用新消息更新通知，例如“MESSAGE2”(也可以正常工作)。

但问题在于:当用户触摸此通知时，Activity 显示的是原始 setMsg(“MESSAGE1”)，而不是“MESSAGE2”。我已经放入 Log.d() 东西来查看过程哪里出了问题，但我没有看到它。该服务很好地记录了传入的“MESSAGE2”，并在 replaceExtras() 之后命中了代码。事实上，传入的值必须是正确的，否则通知不会更新为“MESSAGE2”。因此，Notification Intent 的 extras bundle 似乎没有正确更新，因为所有其他往返的东西都工作正常。或者，不太可能， Activity 仅在第一次尝试时正常工作？

所以我质疑我更新通知的方法。我相信它是“按照书本”，但作为一个相对的 android 新手，有很多书我还没有读过。感谢您的指点。这是服务代码:

package yada.yada.boom.Setlines;

import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.os.IBinder;
import android.text.ClipboardManager;
import android.util.Log;

public class NoteManager extends Service {

    private NotificationManager mNM = null;
    private Notification notification = null;
    private Context context;
    private final CharSequence contentTitle = "Setlines";
    private CharSequence contentText;
    private Intent notificationIntent;
    private PendingIntent pendingIntent;
    private int notificationId = 0;
    private final String MY_TAG = "SetlinesSvc";

    @Override
    public void onCreate() {
        super.onCreate();
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        long setNbr = 0L;
        String setMsg = null;

        super.onStartCommand(intent, flags, startId);
        context = getApplicationContext();
        if (intent != null) {
            Bundle extras = intent.getExtras();
            if (extras != null) {
                setNbr = extras.getLong(getString(R.string.intent_key_setnbr));
                setMsg = extras
                        .getString(getString(R.string.intent_key_setmsg));
            }
        }
        if ((setNbr == 0L) || (setMsg == null)) {
            Log.d(MY_TAG, "Setting default message.");
            setNbr = 0L;
            setMsg = "Click to view setMsg.";
        } else {
            Log.d(MY_TAG, "Got set number (" + setNbr + ") and string ("
                    + setMsg.substring(0, 10) + "...) from intent.");
        }
        if (notification == null) {
            createNotification(setNbr, setMsg);
        } else {
            updateNotificationText(setNbr, setMsg);
        }
        return START_STICKY;
    }

    @Override
    public void onDestroy() {
        // Log.d(MY_TAG, "onDestroy() called");
        mNM.cancel(notificationId);
        super.onDestroy();
    }

    @Override
    public IBinder onBind(Intent arg0) {
        // TODO Auto-generated method stub
        return null;
    }

    // Create a status bar notification
    void createNotification(long setNbr, String setMsg) {
        CharSequence tickerText = null;
        int icon = 0;

        // Log.d(MY_TAG, "createNotification called");
        mNM = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

        icon = R.drawable.ic_notification;
        tickerText = "Setlines";

        // Instantiate the Notification

        long when = System.currentTimeMillis();

        notification = new Notification(icon, tickerText, when);

        context = getApplicationContext();
        contentText = setMsg;
        notificationIntent = new Intent(this, SetServiceMenu.class);
        Bundle bundle = new Bundle();
        bundle.putLong(getString(R.string.intent_key_setnbr), setNbr);
        if (setNbr != 0L) {
            bundle.putString(getString(R.string.intent_key_setmsg), setMsg);
            Log.d(MY_TAG, "Added extras: SetNbr(" + setNbr + ") SetMsg("
                    + setMsg.substring(0, 10) + "...)");
            notificationIntent.putExtras(bundle);
        }
        pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent,
                PendingIntent.FLAG_ONE_SHOT);
        notification.setLatestEventInfo(context, contentTitle, contentText,
                pendingIntent);
        notificationId += 1; // Bump the notification ID number
        // Pass the Notification to the NotificationManager:
        Log.d(MY_TAG, "createNotification() ... passing notification");
        mNM.notify(notificationId, notification);
        startForeground(notificationId, notification);
    }

    void updateNotificationText(long setNbr, String setMsg) {
        contentText = setMsg;
        notificationIntent = new Intent(this, SetServiceMenu.class);
        Bundle bundle = new Bundle();
        bundle.putLong(getString(R.string.intent_key_setnbr), setNbr);
        bundle.putString(getString(R.string.intent_key_setmsg), setMsg);
        // notificationIntent.putExtras(bundle);
        notificationIntent.replaceExtras(bundle);
            Log.d(MY_TAG, "Replaced extras: SetNbr(" + setNbr + ") SetMsg("
                    + setMsg.substring(0, 10) + "...)");
        pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent,
                PendingIntent.FLAG_ONE_SHOT);
        notification.setLatestEventInfo(context, contentTitle, contentText,
                pendingIntent);

        mNM.notify(notificationId, notification);
    }

}

...这是被调用的 Activity 的 onCreate:

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    context = this.getApplicationContext();
    Bundle extras = getIntent().getExtras();
    String setMsg = "";

    dbAdapter = new SetDbAdapter(context);

    dbAdapter.openReadable();
    if (savedInstanceState != null) {
        setNbr = savedInstanceState.getLong("setNbr");
        // Log.d(MY_TAG, "Retrieved set# (" + setNbr + ") from intent.");
        setMsg = savedInstanceState.getString("setMsg");
        // Log.d(MY_TAG, "Retrieved text (" + setMsg.substring(0, 10)
        // + "...) from intent.");
        setMsg = dbAdapter.getSetById(setNbr);
    } else if (extras != null) {
        setNbr = extras.getLong(getString(R.string.intent_key_setnbr));
        // Log.d(MY_TAG, "Retrieved set# (" + setNbr + ") from extras.");
        setMsg = extras.getString(getString(R.string.intent_key_setline));

        if ((setMsg == null) && (setNbr != 0)) {
            setMsg = dbAdapter.getSetById(setNbr);
        }
    }
    if ((setNbr == 0) || (setMsg == null)) {
        setNbr = nextMessageNbr();
        setMsg = messageText(setNbr);
    }
    dbAdapter.close();
    svcTagNbr = setNbr;
    svcTagline = setMsg;
    d = new myDialog(this);
    d.show();
    notifyService(false);
}

最后，这里是notifyService()

private void notifyService(boolean getNew) {

  // Here we get a new setMsg, and notify the server to create
  // notification with it.
  long mySetNbr = svcSetNbr;
  String mySetMsg = svcSetMsg;

  if (getNew) {
    mySetNbr = nextMessageNbr();
    mySetline = messageText(mySetNbr);
  }

  Intent srvIntent = new Intent(context, SetManager.class);
  Bundle bundle = new Bundle();
  bundle.putLong(getString(R.string.intent_key_setnbr), mySetNbr);
  bundle.putString(getString(R.string.intent_key_setmsg), mySetMsg);
  srvIntent.putExtras(bundle);
  startService(srvIntent);
}

这一切都因为我似乎无法找到调试服务的方法而变得更加复杂。任何有关调试服务的指示也将不胜感激!

Answer 1

找到了!问题出在丢失的标志上。显然，即使我们使用 updateExtras()，Android 也不会注意，除非您在 getActivity() 方法上使用特殊标志 (FLAG_UPDATE_CURRENT)。

来自 http://developer.android.com/reference/android/app/PendingIntent.html 的文档:

...如果所描述的 PendingIntent 已经存在，则保留它，但用这个新 Intent 中的内容替换它的额外数据。如果您正在创建只有 extras 发生变化的 intent，并且不关心收到您之前的 PendingIntent 的任何实体将能够使用您的新 extras 启动它，即使它们没有明确提供给它，也可以使用它。

所以新代码看起来像:

void updateNotificationText(long setNbr, String setMsg) {
    contentText = setMsg;
    Bundle bundle = new Bundle();
    bundle.putLong(getString(R.string.intent_key_setnbr), setNbr);
    bundle.putString(getString(R.string.intent_key_setmsg), setMsg);
    notificationIntent.replaceExtras(bundle);
    pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent,
          PendingIntent.FLAG_ONE_SHOT
        + PendingIntent.FLAG_UPDATE_CURRENT);
    notification.setLatestEventInfo(context, contentTitle, contentText,
            pendingIntent);
    mNM.notify(notificationId, notification);
}