我希望能够在通知栏中显示文件的多个下载，这也可以取消。
我已经实现了一个自定义服务，它使用 AsyncTasks 并行执行多个下载。OnPublishProgress 我正在尝试更新通知栏中的各个行以显示每个文件的下载进度。两天来，我一直在尝试解决行闪烁、交换顺序以及有时只是空白或仅更新一行的问题。此外，点击该行取消例程并不总是有效。
这是我的代码：
protected void showProgressNotification(final File item, int progress, boolean isDownloading) {
String message = null;
int smallIcon = 0;
Bitmap largeIcon = null;
int flags = 0;
flags |= Notification.FLAG_ONGOING_EVENT;
//flags |= Notification.FLAG_FOREGROUND_SERVICE;
//flags |= Notification.FLAG_ONLY_ALERT_ONCE;
//flags |= Notification.FLAG_AUTO_CANCEL;
NotificationCompat.Builder builder =
new NotificationCompat.Builder(getApplicationContext());
builder.setAutoCancel(true);
if (progress == 100) {
largeIcon = BitmapFactory.decodeResource(getResources(),
O2FolderListAdapter.getIconForItem(item, false));
smallIcon = R.drawable.ic_cloud_upto_date;
if (isDownloading) {
message = "Download completed. Tap to clear.";
} else {
message = "Upload completed. Tap to clear.";
}
} else if (progress >= 0) {
largeIcon = BitmapFactory.decodeResource(getResources(),
O2FolderListAdapter.getIconForItem(item, true));
if (isDownloading) {
smallIcon = R.drawable.ic_cloud_downloading;
message = "Downloading: " + progress + "%. Tap to cancel.";
} else {
smallIcon = R.drawable.ic_cloud_uploading;
message = "Uploading: " + progress + "%. Tap to cancel.";
}
builder.setProgress(100, progress, false);
} else {
largeIcon = BitmapFactory.decodeResource(getResources(),
O2FolderListAdapter.getIconForItem(item, true));
smallIcon = R.drawable.ic_cloud_conflict;
if (isDownloading)
message = "Cancelled download. Tap to clear.";
else
message = "Cancelled upload. Tap to clear.";
}
if (mResultIntent == null) {
mResultIntent = new Intent(getApplicationContext(), CustomDownloadService.class);
mResultIntent.addFlags(Notification.FLAG_ONGOING_EVENT);
}
mResultIntent.putExtra("cancel", item.getPath().hashCode());
Log.d("O2AbstractDownloadService", "Setup task id " + item.GetPath().hashCode());
if (mContentIntent == null)
mContentIntent = PendingIntent.getService(getApplicationContext(), PI_REQ_CODE, mResultIntent, PendingIntent.FLAG_UPDATE_CURRENT);
builder.setContentIntent(mContentIntent);
builder.setLargeIcon(largeIcon);
builder.setSmallIcon(smallIcon);
builder.setContentTitle(item.GetName());
builder.setContentText(message);
//if (progress != 100)
//builder.addAction(R.drawable.ic_action_dark_cancel, "Cancel", contentIntent);
final Notification notification = builder.build();
notification.flags = flags;
notification.defaults = Notification.DEFAULT_LIGHTS;
NotificationManager mNotificationManager =
(NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
// Id allows you to update the notification later on.
//mNotificationManager.notify(item.getPath().hashCode(), notification);
//startForeground(item.getPath().hashCode(), notification);
// only update notification every 100ms (unless cancel or complete)
long notificationDelay = 100;
long now = System.currentTimeMillis();
if (mFutureCallTime == 0 || now > mFutureCallTime || progress == -1 || progress == 100) {
startForeground(item.getPath().hashCode(), notification);
//mNotificationManager.notify(item.GetPath().hashCode(), notification);
} else
Log.d("CustomDownloadService", "Called too often to notification");
mFutureCallTime = now + notificationDelay;
}
所以我试图设置在点击通知时调用服务的操作，传递文件的 id 以取消下载。谁能看到我做错了什么？我所追求的真的可能吗？在 Xoom 平板电脑上，通知闪烁很多，但在 Nexus 7 上则不经常闪烁。所有设备最终都会不断地交换行，这意味着几乎不可能取消您想要的下载。
任何建议将不胜感激。
更新 1：我认为这可能导致我的问题之一： Android Service.startForeground 不尊重通知 ID 唯一性
更新 2：通过调用 builder.setWhen(fixedTime) 修复了换出问题。显然，新的 dateTime 会导致行在每次刷新时重新排序。只需修复 Xoom 上的闪烁和“点击取消”功能即可。
更新 3： Xoom 上的闪烁已通过限制刷新调用得到修复。最后的代码防止通知在每 100 毫秒内被更新一次以上。剩下的问题与取消有关。点击取消第一次有效，但不适用于后续文件。我也无法清除行。
更新 4：单个取消问题是由 resultIntent 字段处于类级别引起的。每次刷新通知时，当我创建一个新通知时，ID 都会绑定。我还将标志更改为仅 Notification.FLAG_ONLY_ALERT_ONCE 并且仅使用了 .notify() 而不是 startForeground()。