尝试在Android O上显示通知时收到此消息。
对于卷以外的操作，不推荐使用流类型 控制
通知直接来自示例文档，并且在Android 25上显示正常。
答案 0 :(得分：60)
根据this Google+ post的评论：
当在Android O设备上使用
NotificationCompat时，预计会出现这些[警告]（即使您从未传递自定义声音，NotificationCompat始终会调用setSound()。）在支持库更改其代码以使用
AudioAttributessetSound版本之前，您将始终收到该警告。
因此，您无法对此警告采取任何措施。根据{{3}}，Android O根本不赞成在单个通知上设置声音，而是让您在特定类型的所有通知所使用的通知通道上设置声音。
答案 1 :(得分：43)
从Android O开始，您需要配置NotificationChannel，并在尝试显示通知时引用该频道。
private static final int NOTIFICATION_ID = 1;
private static final String NOTIFICATION_CHANNEL_ID = "my_notification_channel";
...
NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
NotificationChannel notificationChannel = new NotificationChannel(NOTIFICATION_CHANNEL_ID, "My Notifications", NotificationManager.IMPORTANCE_DEFAULT);
// Configure the notification channel.
notificationChannel.setDescription("Channel description");
notificationChannel.enableLights(true);
notificationChannel.setLightColor(Color.RED);
notificationChannel.setVibrationPattern(new long[]{0, 1000, 500, 1000});
notificationChannel.enableVibration(true);
notificationManager.createNotificationChannel(notificationChannel);
}
NotificationCompat.Builder builder = new NotificationCompat.Builder(this, NOTIFICATION_CHANNEL_ID)
.setVibrate(new long[]{0, 100, 100, 100, 100, 100})
.setSound(RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION))
.setSmallIcon(R.mipmap.ic_launcher)
.setContentTitle("Content Title")
.setContentText("Content Text");
notificationManager.notify(NOTIFICATION_ID, builder.build());
一些重要的注意事项：
NotificationChannel中指定的振动模式等设置会覆盖实际Notification中指定的振动模式。我知道，它反直觉。您应该移动将更改为通知的设置，或者为每个配置使用不同的NotificationChannel。NotificationChannel设置传递给createNotificationChannel()后，您无法修改大部分deleteNotificationChannel()设置。您甚至无法呼叫NotificationChannel，然后尝试重新添加它。使用已删除的<%= form_for :subscribe, id: 'sub_form' do |f| %>
<input type="email" name="email" placeholder="Your email address" id="sub_email">
<button class="btn btn-success" type="submit" id="sub_btn">Subscribe</button><br>
<p id="sub_output" class="lead" style="color: white;"></p>
<% end %>
的ID将会复活它，它将与首次创建时一样不可变。在卸载应用程序之前，它将继续使用旧设置。因此，您最好确定自己的频道设置，如果您正在使用这些设置，请重新安装该应用，以使其生效。答案 2 :(得分：8)
@ sky-kelsey所描述的一切都很好，只是轻微的补充：
如果已经注册了，那么每次都不应该注册相同的频道，所以我有Utils类方法为我创建一个频道：
public static final String NOTIFICATION_CHANNEL_ID_LOCATION = "notification_channel_location";
public static void registerLocationNotifChnnl(Context context) {
if (Build.VERSION.SDK_INT >= 26) {
NotificationManager mngr = (NotificationManager) context.getSystemService(NOTIFICATION_SERVICE);
if (mngr.getNotificationChannel(NOTIFICATION_CHANNEL_ID_LOCATION) != null) {
return;
}
//
NotificationChannel channel = new NotificationChannel(
NOTIFICATION_CHANNEL_ID_LOCATION,
context.getString(R.string.notification_chnnl_location),
NotificationManager.IMPORTANCE_LOW);
// Configure the notification channel.
channel.setDescription(context.getString(R.string.notification_chnnl_location_descr));
channel.enableLights(false);
channel.enableVibration(false);
mngr.createNotificationChannel(channel);
}
}
的strings.xml：
<string name="notification_chnnl_location">Location polling</string>
<string name="notification_chnnl_location_descr">You will see notifications on this channel ONLY during location polling</string>
在我要显示类型通知之前，我每次都会调用该方法：
...
NotificationUtil.registerLocationNotifChnnl(this);
return new NotificationCompat.Builder(this, NotificationUtil.NOTIFICATION_CHANNEL_ID_LOCATION)
.addAction(R.mipmap.ic_launcher, getString(R.string.open_app),
activityPendingIntent)
.addAction(android.R.drawable.ic_menu_close_clear_cancel, getString(R.string.remove_location_updates),
servicePendingIntent)
.setContentText(text)
...
另一个典型问题 - 频道默认声音 - 此处描述：https://stackoverflow.com/a/45920861/2133585
答案 3 :(得分：2)
在Android O中，必须使用NotificationCompat.Builder mBuilder =
new NotificationCompat.Builder(mContext.getApplicationContext(), "notify_001");
Intent ii = new Intent(mContext.getApplicationContext(), RootActivity.class);
PendingIntent pendingIntent = PendingIntent.getActivity(mContext, 0, ii, 0);
NotificationCompat.BigTextStyle bigText = new NotificationCompat.BigTextStyle();
bigText.bigText(verseurl);
bigText.setBigContentTitle("Today's Bible Verse");
bigText.setSummaryText("Text in detail");
mBuilder.setContentIntent(pendingIntent);
mBuilder.setSmallIcon(R.mipmap.ic_launcher_round);
mBuilder.setContentTitle("Your Title");
mBuilder.setContentText("Your text");
mBuilder.setPriority(Notification.PRIORITY_MAX);
mBuilder.setStyle(bigText);
NotificationManager mNotificationManager =
(NotificationManager) mContext.getSystemService(Context.NOTIFICATION_SERVICE);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
NotificationChannel channel = new NotificationChannel("notify_001",
"Channel human readable title",
NotificationManager.IMPORTANCE_DEFAULT);
mNotificationManager.createNotificationChannel(channel);
}
mNotificationManager.notify(0, mBuilder.build());
并且input已被弃用（reference）。
以下是示例代码：
<form action="tambahMatkul.php" method="post" id="ambil_matkul">
<table class="tabel table-bordered table-stripped table-responsive">
<tr>
<th width="5%">cek</th>
<th width="19%">Kode</th>
<th width="19%">Mata Kuliah</th>
<th width="19%">W/P</th>
<th width="19%">SKS</th>
<th width="19%">Kelas</th>
</tr>
<?php include "koneksi.php";
$query = $connect->query("SELECT * FROM matakuliah")or die(mysqli_error($connect));
while($mahasiswa = $query->fetch_array()){
?>
<tr>
<td><input type="checkbox" name="cek[]" value="<?php echo $mahasiswa['kodeMatkul'] ?>" /></td>
<td><?php echo $mahasiswa['kodeMatkul']; ?></td>
<td><?php echo $mahasiswa['namaMatkul']; ?></td>
<td><?php echo $mahasiswa['pilihan']; ?></td>
<td><?php echo $mahasiswa['sks']; ?></td>
<td><?php echo $mahasiswa['kelas']; ?></td>
</tr>
<?php } ?>
</table>
<hr/>
<div class="btn-group"><button class="btn btn-sm btn-success" type="submit"><i class="fa fa-plus"></i> Tambah</button></div>
</form>