[置顶] Android Wear 进阶 1 Adding Wearable Features to Notifications 添加手表特性到通知上

Adding Wearable Features to Notifications

添加手表特性到通知上面

Get started

Dependencies and prerequisites

• Android 4.3 (API Level 18) or higher on the handset device
• An Android Wear device or Wear AVD
• The Android v4 support library (or v13, which includes v4)

You should also read

• Android Wear Design Principles

When an Android handheld (phone or tablet) and Android wearable are connected, the handheld automatically shares notifications with the wearable. On the wearable, each notification appears as a new card in the context stream.

However, to give users the best experience, you should add wearable-specific functionality to the notifications you already create. The following lessons show you how to create notifications that are catered for handhelds and wearables at the same time.

<翻译>当一个手机端和手表连接后。手表会自动分享通知到手表端。在手表上面，每一个个通知将会以新的卡片card的形式在上下文流中，（其实就是手表的界面上面）。

然而，为了给用户更好的体验，你应该增加手表特殊的功能到你已经创建了的通知上面。下面的课程展示你怎么去一次创建手表端和手机端不同目录的通知的。

Figure 1. The same notification displayed on a handheld and wearable.

图表1：同样的通知战士在手表端和手机端。

Lessons课程

1  Creating a notification 创建一个通知

Learn how to create notifications with wearable features with the Android support library.

学习如何通过Android 支持包 support library 来创建有手表特性的通知

2  Receiving Voice Input in a Notification 接收通知中的语言输入

Learn how to add an action to a wearable notification that receives voice input from users and delivers the transcribed message to your handset app.

学习如何去给手表通知添加一个action。这个action 可以用来接收用户的声音输入并且将可以翻译了信息传给你的手机应用。

3  Adding Pages to a Notification添加页面到通知

Learn how to add additional pages of information that are visible when the user swipes to the left.

学习如何添加信息页面，这个信息页面在用户从左滑动通知的时候可见。

4  Stacking Notifications 堆积通知

Learn how to place all similar notifications from your app in a stack, allowing users to view each notification individually without adding multiple cards to the card stream.

学习如何去将类似的通知放子啊一个堆里面，这个允许用户去查看每一个通知而不需要多个卡片在卡片流里面。

1 Creating a Notification for Wearables

1,创建手表的通知

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Previous Next

This lesson teaches you to

1. Import the Necessary Classes
2. Create Notifications with the Notification Builder
3. Add Action Buttons
4. Specify Wearable-only Actions
5. Add a Big View
6. Add Wearable Features for a Notification
7. Deliver the Notification

To build handheld notifications that are also sent to wearables, use NotificationCompat.Builder. When you build notifications with this class, the system takes care of displaying notifications properly, whether they appear on a handheld or wearable.

<翻译>为了创建可以发送给手表端的手机的通知，使用NotificationCompat.Builder.来创建通知。当你使用这个类来创建通知的时候，系统会考虑将通知正确的展示，是否要让他们出现在手机端或者手表端。

Note: Notifications using RemoteViews are stripped of custom layouts and the wearable only displays the text and icons. However, you can create create custom notificationsthat use custom card layouts by creating a wearable app that runs on the wearable device.

<翻译>注意通知使用RemoteViews的话，会出去自定义的布局，并且手表端只显示文字和icons。然后你可以创建“自定义的通知” 这个自定义的通知可以自定义卡片布局，它通过创建一个运行在手表设备上面的手表应用。

Import the necessary classes导入必须的类

To import the necessary packages, add this line to yourbuild.gradlefile:

为了导入必须的类，将下面的话添加到你的build.gradle文件中。

compile "com.android.support:support-v4:20.0.+"

Now that your project has access to the necessary packages, import the necessary classes from the support library:

现在你的项目可以访问必须的包，可以从这个库中导入我们需要的包

import android.support.v4.app.NotificationCompat;
import android.support.v4.app.NotificationManagerCompat;
import android.support.v4.app.NotificationCompat.WearableExtender;

Create Notifications with the Notification Builder

通过Notification Builder来创建通知

The v4 support library allows you to create notifications using the latest notification features such as action buttons and large icons, while remaining compatible with Android 1.6 (API level 4) and higher.

v4支持包允许你去创建通知，这个通知里面可以使用通知的特性例如action 的按钮和大的icon，可以和 Android 1.6 (API level 4) 或者更高的版本保持兼容。

To create a notification with the support library, you create an instance of NotificationCompat.Builder and issue the notification by passing it to notify(). For example:

为了使用支持包来创建通知，你可以创建一个 NotificationCompat.Builder 的实例并且可以通过将这个传给notify()的方法来

int notificationId = 001;
// Build intent for notification content
Intent viewIntent = new Intent(this, ViewEventActivity.class);
viewIntent.putExtra(EXTRA_EVENT_ID, eventId);
PendingIntent viewPendingIntent =
        PendingIntent.getActivity(this, 0, viewIntent, 0);

NotificationCompat.Builder notificationBuilder =
        new NotificationCompat.Builder(this)
        .setSmallIcon(R.drawable.ic_event)
        .setContentTitle(eventTitle)
        .setContentText(eventLocation)
        .setContentIntent(viewPendingIntent);

// Get an instance of the NotificationManager service
NotificationManagerCompat notificationManager =
        NotificationManagerCompat.from(this);

// Build the notification and issues it with notification manager.
notificationManager.notify(notificationId, notificationBuilder.build());

When this notification appears on a handheld device, the user can invoke the PendingIntent specified by thesetContentIntent() method by touching the notification. When this notification appears on an Android wearable, the user can swipe the notification to the left to reveal the Open action, which invokes the intent on the handheld device.

<翻译>当这个通知出现在了手机设备上，用户可以通过点击通知来触发PendingIntent，这个PendingIntent 通过setContentIntent()来指定。

当这个通知出现在手表上面，用户可以通过从左向右滑动通知去显示打开的action，这个action 会出发在手机设备上面的actionl。

Add Action Buttons 添加action 的按钮

In addition to the primary content action defined bysetContentIntent(), you can add other actions by passing aPendingIntent to the addAction() method.

For example, the following code shows the same type of notification from above, but adds an action to view the event location on a map.

<翻译>除了通过setContentIntentn()方法来定义的主要的内容，你还可以通过给PendingIntent 传送一个addAction()的方法来添加其他的额action。

例如在下面的代码中显示了和上面相同的通知类型，但是添加了一个action 去在地图上查看事件发生的地理位置。

// Build an intent for an action to view a map
Intent mapIntent = new Intent(Intent.ACTION_VIEW);
Uri geoUri = Uri.parse("geo:0,0?q=" + Uri.encode(location));
mapIntent.setData(geoUri);
PendingIntent mapPendingIntent =
        PendingIntent.getActivity(this, 0, mapIntent, 0);

NotificationCompat.Builder notificationBuilder =
        new NotificationCompat.Builder(this)
        .setSmallIcon(R.drawable.ic_event)
        .setContentTitle(eventTitle)
        .setContentText(eventLocation)
        .setContentIntent(viewPendingIntent) 是否要删除这一行？
        .addAction(R.drawable.ic_map,                 getString(R.string.map), mapPendingIntent);

On a handheld, the action appears as an additional button attached to the notification. On a wearable, the action appears as a large button when the user swipes the notification to the left. When the user taps the action, the associated intent is invoked on the handheld.

在手机端，一个action在通知上面显示的是一个增加的按钮。在手表端，显示的是一个大的按钮，这个按钮在用户从左向右的滑动的时候显示。

当用户点击了这个action，相关的intent将会在手机端出发。

Tip: If your notifications include a "Reply" action (such as for a messaging app), you can enhance the behavior by enabling voice input replies directly from the Android wearable. For more information, read Receiving Voice Input from a Notification.

提示：如果你的通知包含了Reply回复的action，例如信息的app上面就有，那么你可以扩展这个行为通过使用android 手表的voice input 声音输入回复。更多的信息，可以查看 Receiving Voice Input from a Notification.

Specify Wearable-onlyActions 制定只是手表段的action

If you want the actions available on the wearable to be different from those on the handheld, then useWearableExtender.addAction(). Once you add an action with this method, the wearable does not display any other actions added with NotificationCompat.Builder.addAction(). That is, only the actions added withWearableExtender.addAction() appear on the wearable and they do not appear on the handheld.

如果你想要action在手表端和在手机端不同，那么请使用WearableExtender.addAction(). 一旦你通过这个方法添加了action，这个手表将不会展示任何其他的通过 NotificationCompat.Builder.addAction().来添加的action 。也就是说，被WearableExtender.addAction() 添加的action只会出现在手表端而不会出现在手机端。

// Create an intent for the reply action
Intent actionIntent = new Intent(this, ActionActivity.class);
PendingIntent actionPendingIntent =
        PendingIntent.getActivity(this, 0, actionIntent,
                PendingIntent.FLAG_UPDATE_CURRENT);

// Create the action
NotificationCompat.Action action =
        new NotificationCompat.Action.Builder(R.drawable.ic_action,
                getString(R.string.label), actionPendingIntent)
                .build();

// Build the notification and add the action via WearableExtender
Notification notification =
        new NotificationCompat.Builder(mContext)
                .setSmallIcon(R.drawable.ic_message)
                .setContentTitle(getString(R.string.title))
                .setContentText(getString(R.string.content))
                .extend(new WearableExtender().addAction(action))
                .build();

Add a Big View添加一个大的视图

You can insert extended text content to your notification by adding one of the "big view" styles to your notification. On a handheld device, users can see the big view content by expanding the notification. On a wearable device, the big view content is visible by default.

你通过添加一个“大图big view”样式到你的通知来插入扩展的消息内容到你的通知。在手机设备上面，用户可以看到大的视图内容通过扩展通知。在手表段，大图的内容直接就是默认的可见的。

To add the extended content to your notification, call setStyle() on theNotificationCompat.Builder object, passing it an instance of eitherBigTextStyle or InboxStyle.

为了添加扩展的内容到你的通知，调用NotificationCompat.Builder 的setStyle()的方法，传送一个要不是BigTextStyle要不是InboxStyle的实例。

For example, the following code adds an instance ofNotificationCompat.BigTextStyle to the event notification, in order to include the complete event description (which includes more text than can fit into the space provided forsetContentText()).

例如，下面的代码添加了NotificationCompat.BigTextStyle的实例到事件的通知，为了包含了事件描述，这个事件描述包含了比setConetentText 的内容更多的内容。

// Specify the 'big view' content to display the long
// event description that may not fit the normal content text.
BigTextStyle bigStyle = new NotificationCompat.BigTextStyle(); bigStyle.bigText(eventDescription);

NotificationCompat.Builder notificationBuilder =
        new NotificationCompat.Builder(this)
        .setSmallIcon(R.drawable.ic_event)
        .setLargeIcon(BitmapFactory.decodeResource(                 getResources(), R.drawable.notif_background))
        .setContentTitle(eventTitle)
        .setContentText(eventLocation)
        .setContentIntent(viewPendingIntent)
        .addAction(R.drawable.ic_map,
                getString(R.string.map), mapPendingIntent)         .setStyle(bigStyle);

Notice that you can add a large icon image to any notification using the setLargeIcon() method. However, these icons appear as large background images on a wearable and do not look good as they are scaled up to fit the wearable screen. To add a wearable-specific background image to a notification, see Add Wearable Features For a Notification. For more information about designing notifications with large images, see the Design Principles of Android Wear.

注意你可以通过setLargeIcon()的方法来添加一个大的icon图片。然而这些icons出现在手表上面显示的时候是作为大的背景图片的，并且这个图片因为没有适配手表屏幕所以看上去不是很好。为了增加特别的手表背景图片到通知，看Add Wearable Features For a Notification. 更多的关于使用大图片设计通知，请看 Design Principles of Android Wear.

Add Wearable Features For a Notification 添加手表特性到通知。

If you ever need to add wearable-specific options to a notification, such as specifying additional pages of content or letting users dictate a text response with voice input, you can use the NotificationCompat.WearableExtenderclass to specify the options. To use this API:

1. Create an instance of a WearableExtender, setting the wearable-specific options for the notication.
2. Create an instance of NotificationCompat.Builder, setting the desired properties for your notification as described earlier in this lesson.
3. Call extend() on the notification and pass in the WearableExtender. This applies the wearable options to the notification.
4. Call build() to build the notification.

For example, the following code calls the setHintHideIcon() method to remove the app icon from the notification card.

如果你需要添加特别的手表项目到一个通知，例如制定增加有内容的page页面或者让用户听写语音输入一个文字回复，你可以使用 NotificationCompat.WearableExtender类来制定这些选项。为了使用这个API:

1:创建一个WearableExtender的实例,设置手表特性的选项给通知

2：创建 NotificationCompat.Builder的实例，设置 一些需要的属性

3：调用通知的的extend()的方法，并且传递到WearableExtender里面。这个应用手表选项到通知上面。

4：调用build()去创建通知

例如下面的代码调用过了setHintHideIcon()方法去从通知的卡片上面一处应用icon

// Create a WearableExtender to add functionality for wearables
NotificationCompat.WearableExtender wearableExtender =
        new NotificationCompat.WearableExtender()
        .setHintHideIcon(true)
        .setBackground(mBitmap);

// Create a NotificationCompat.Builder to build a standard notification
// then extend it with the WearableExtender
Notification notif = new NotificationCompat.Builder(mContext)
        .setContentTitle("New mail from " + sender)
        .setContentText(subject)
        .setSmallIcon(R.drawable.new_mail)
        .extend(wearableExtender)
        .build();

The setHintHideIcon() and setBackground() methods are just two examples of new notification features available with NotificationCompat.WearableExtender.

方法 setHintHideIcon() 和 setBackground() 只是 NotificationCompat.WearableExtender.中的两个新的可用的特性的例子

Note: The bitmap that you use with setBackground() should have a resolution of 400x400 for non-scrolling backgrounds and 640x400 for backgrounds that support parallax scrolling. Place these bitmap images in theres/drawable-nodpi directory. Place other non-bitmap resources for wearable notifications, such as those used with the setContentIcon() method, in the res/drawable-hdpi directory.

注意：你使用setBackground()方法设置的背景图片应该使用400*400的给不是滑动的背景，640*400给支持水平滑动滑动的背景。将这些图片放在 drawable-nodpi  目录下面，将其他的不是手表通知的非图片资源防止在res/drawable-hdpi目录下。

If you ever need to read wearable-specific options at a later time, use the corresponding get method for the option. This example callsthe getHintHideIcon() method to get whether or not this notification hides the icon:

如果你之后需要读取手表特别的选项，使用相关的选项的get方法。这里例子调用了getHitHideIcon()方法去得到是否这个通知隐藏了icon了。

NotificationCompat.WearableExtender wearableExtender =
        new NotificationCompat.WearableExtender(notif);
boolean hintHideIcon = wearableExtender.getHintHideIcon();

Deliver the Notification 发送通知

When you want to deliver your notifications, always use the NotificationManagerCompat API instead ofNotificationManager:

当你想要发送 你的额通知，一般是使用 NotificationManagerCompat 接口API而不是NotificationManager:

// Get an instance of the NotificationManager service
NotificationManagerCompat notificationManager =
        NotificationManagerCompat.from(mContext);

// Issue the notification with notification manager.
notificationManager.notify(notificationId, notif);

If you use the framework's NotificationManager, some features from NotificationCompat.WearableExtenderdo not work, so make sure to use NotificationCompat. （should be NotificationManagerCompat）

如果你使用了框架的 NotificationManager, 一些 NotificationCompat.WearableExtender中的特性就不能使用了，所以要保证使用NotificationManagerCompat

2 Receiving Voice Input in a Notification 在通知中接收语音输入

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Previous Next

This lesson teaches you to

1. Define the Voice Input
2. Add the Voice Input as a Notification Action
3. Receiving the Voice Input as a String

If you have handheld notifications that include an action to input text, such as reply to an email, it should normally launch an activity on the handheld device to input the text. However, when your notification appears on a wearable, there is no keyboard input, so you can let users dictate a reply or provide pre-defined text messages using RemoteInput.

如果你的手机通知包含了一个action去输入文字，例如回复一个email，他应该启动一个手机设备上面的额activity 去输入文字。然而，当通知出现在手表端的时候，没有按键输入，所以你可以让用户说出一个回复或者准备一些使用RemoteInput提前定义的文字信息

When users reply with voice or select one of the available messages, the system attaches the text response to the Intentyou specified for the notification action and sends that intent to your handheld app.

当用户使用语音回复或者选择了一个合适的信息，系统将这些信息反馈给你的制定通知action的intent，并且将这个intent发送给你的应用。

Note: The Android emulator does not support voice input. When using the emulator for a wearable device, enableHardware keyboard present in the AVD settings so you can type replies instead.

注意：Android 模拟器不支持声音输入。当使用手表的模拟器的时候，确定Hardware keyboard present这个设置已经开启，这样可以按键输入。

Define the Voice Input定义语音输入

To create an action that supports voice input, create an instance of RemoteInput.Builder that you can add to your notification action. This class's constructor accepts a string that the system uses as the key for the voice input, which you'll later use to retrieve the text of the input in your handheld app.

为了创建一个支持声音输入的action，使用RemoteInput.Builder 的实例，这个实例可以被添加到通知的action 中。这个类的构造方法接收一个字符串，系统将会使用这个字符串作为声音输入的key，你将会使用这个来恢复在你手机应用中输入的信息。

For example, here's how to create a RemoteInput object that provides a custom label for the voice input prompt:

例如，这里是怎么创建RemoteInput 对象，这个对象为了声音输入提示提供了一个自定义的标签：

// Key for the string that's delivered in the action's intent
private static final String EXTRA_VOICE_REPLY = "extra_voice_reply";

String replyLabel = getResources().getString(R.string.reply_label);

RemoteInput remoteInput = new RemoteInput.Builder(EXTRA_VOICE_REPLY)
        .setLabel(replyLabel)
        .build();

Add Pre-defined Text Responses 添加预定义的文字回复

In addition to allowing voice input, you can provide up to five text responses that the user can select for quick replies. Call setChoices() and pass it a string array.

For example, you can define some responses in a resource array:

除了可以允许语音输入，你也可以提供5个文字回复，这些回复用户可以快速的来选择回复。调用setChoices()方法并且将一个字符串数组传给它。

例如，你可以在资源数组中定义一些回复

res/values/strings.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string-array name="reply_choices">
        <item>Yes</item>
        <item>No</item>
        <item>Maybe</item>
    </string-array>
</resources>

Then, inflate the string array and add it to the RemoteInput:

然后，将这个字符串数组填充并且添加到RemoteInput中。

public static final String EXTRA_VOICE_REPLY = "extra_voice_reply";
...
String replyLabel = getResources().getString(R.string.reply_label);
String[] replyChoices = getResources().getStringArray(R.array.reply_choices);

RemoteInput remoteInput = new RemoteInput.Builder(EXTRA_VOICE_REPLY)
        .setLabel(replyLabel)
        .setChoices(replyChoices)
        .build();

Add the Voice Input as a Notification Action添加语音输入作为通知的action

To set the voice input, attach your RemoteInput object to an action using addRemoteInput(). You can then apply the action to the notification. For example:

为了设置语音输入，使用addRemoteInput方法来将你的RmoteInput 对象赋值到一个action 上面。你可以将action赋值给通知了。

// Create an intent for the reply action
Intent replyIntent = new Intent(this, ReplyActivity.class);
PendingIntent replyPendingIntent =
        PendingIntent.getActivity(this, 0, replyIntent,
                PendingIntent.FLAG_UPDATE_CURRENT);

// Create the reply action and add the remote input
NotificationCompat.Action action =
        new NotificationCompat.Action.Builder(R.drawable.ic_reply_icon,
                getString(R.string.label), replyPendingIntent)                 .addRemoteInput(remoteInput)
                .build();

// Build the notification and add the action via WearableExtender
Notification notification =
        new NotificationCompat.Builder(mContext)
                .setSmallIcon(R.drawable.ic_message)
                .setContentTitle(getString(R.string.title))
                .setContentText(getString(R.string.content))
                .extend(new WearableExtender().addAction(action))
                .build();

// Issue the notification
NotificationManagerCompat notificationManager =
        NotificationManagerCompat.from(mContext);
notificationManager.notify(notificationId, notification);

When you issue this notification, users can swipe to the left to see the "Reply" action button.

当出发了这个通知，用户可以从左向右的滑动，然后看到Reply的action 按钮。

Receiving the Voice Input as a String将语音输入作为字符串接收

To receive the user's transcribed message in the activity you declared in the reply action's intent, callgetResultsFromIntent(), passing in the "Reply" action's intent. This method returns a Bundle that contains the text response. You can then query the Bundle to obtain the response.

为了接收到在activity中翻译了用户的信息，（这个activity是你声明的reply的action的intent），调用getResultFromIntent()方法。这个方法反悔一个Bundle，这个bundle包含了文字回复，你可以获取Bundle去得到这个回复。

Note: Do not use Intent.getExtras() to obtain the voice result, because the voice input is stored asClipData. The getResultsFromIntent() method provides a convenient way to receive a character sequence without having to process the ClipData yourself.

注意不要使用Intent.getExtras（）去获取声音输入的结果，因为生意输入是以ClipData存储的。方法e getResultsFromIntent() 提供了一个方便的方法去获取字符串而不用自己使用处理ClipData

The following code shows a method that accepts an intent and returns the voice response, which is referenced by the EXTRA_VOICE_REPLY key that is used in the previous examples:

下面的代码显示了一个方法，这个方法接收了一个intent并且反悔了声音回复，这个是参考了 EXTRA_VOICE_REPLY 这个key。这个key 在上面被使用到的。

/**
 * Obtain the intent that started this activity by calling
 * Activity.getIntent() and pass it into this method to
 * get the associated voice input string.
 */

private CharSequence getMessageText(Intent intent) {
    Bundle remoteInput = RemoteInput.getResultsFromIntent(intent);
    if (remoteInput != null) {
        return remoteInput.getCharSequence(EXTRA_VOICE_REPLY);
    }
    return null;
}

3: Adding Pages to a Notification

给通知添加Page页面

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Previous Next

This lesson teaches you to

1. Add Pages to a Notification

When you'd like to provide more information without requiring users to open your app on their handheld device, you can add one or more pages to the notification on the wearable. The additional pages appear immediately to the right of the main notification card.

当你想要去给用户提供更多的信息而不用在手表端打开应用的时候，你可以添加一个或者更多的页面到手表的通知上面，增加的页面将会出现在主通知的card的右边。

 

To create a notification with multiple pages:

1. Create the main notification (the first page) with NotificationCompat.Builder, in the way you'd like the notification to appear on a handset.
2. Create the additional pages for the wearable with NotificationCompat.Builder.
3. Apply the pages to the main notification with the addPage() method or add multiple pages in a Collectionwith the addPages() method.

For example, here's some code that adds a second page to a notification:

<翻译>为了创建有多个page页面的通知:

1:使用NotificationCompat.Builder,创建主要的通知（就是第一个page），以你想要在手机端显示的方式

2：.使用NotificationCompat.Builder创建增加的手表页面

3：通过使用addPage()方法来将page放到主通知，或者使用addPages（）来添加多个页面集合

例如下面是添加第二个page 页面到通知的代码

// Create builder for the main notification
NotificationCompat.Builder notificationBuilder =
        new NotificationCompat.Builder(this)
        .setSmallIcon(R.drawable.new_message)
        .setContentTitle("Page 1")
        .setContentText("Short message")
        .setContentIntent(viewPendingIntent);

// Create a big text style for the second page
BigTextStyle secondPageStyle = new NotificationCompat.BigTextStyle();
secondPageStyle.setBigContentTitle("Page 2")
               .bigText("A lot of text...");

// Create second page notification
Notification secondPageNotification =
        new NotificationCompat.Builder(this)
        .setStyle(secondPageStyle)
        .build();

// Extend the notification builder with the second page
Notification notification = notificationBuilder         .extend(new NotificationCompat.WearableExtender()
                .addPage(secondPageNotification))
        .build();

// Issue the notification
notificationManager =
        NotificationManagerCompat.from(this);
notificationManager.notify(notificationId, notification);

4：Stacking Notifications把通知堆起来

Previous Next

This lesson teaches you to

1. Add Each Notification to a Group
2. Add a Summary Notification

When creating notifications for a handheld device, you should always aggregate similar notifications into a single summary notification. For example, if your app creates notifications for received messages, you should not show more than one notification on a handheld device—when more than one is message is received, use a single notification to provide a summary such as "2 new messages."

当创建手表设备的通知的时候，你应该将类似的通知聚合到一个单独的总结的通知。例如如果你的应用创建了收到短息的通知，你不应该在手机设备上面显示多个通知，而是应该一个总结“2条信息”

However, a summary notification is less useful on anAndroid wearable because users are not able to read details from each message on the wearable (they must open your app on the handheld to view more information).So for the wearable device, you should group all the notifications together in a stack.The stack of notifications appears as a single card, which users can expand to view the details from each notification separately. The new setGroup()method makes this possible while allowing you to still provide only one summary notification on the handheld device.

然而，一个总结的通知对于android 手表来说是没有什么用的，因为用户不能在手表上面读取每条信息的内容（你必须打开你的手机应用去读取）所以对于手表设备，你应该将所有的通知都分组在一个堆里面。这个通知堆，以一个单独的卡片显示，用户可以张卡这个卡片card去看每一个单独的通知的信息。新的setGroup() 方法使得你在手机端还是只是显示一个总结的通知。

Add Each Notification to a Group将每个通知添加到组中

To create a stack, call setGroup() for each notification you want in the stack and specify a group key. Then callnotify() to send it to the wearable.为了创建堆，调用setGroup的方法给每你想要把他放到堆中的通知，指定组的key。然后调用notify()去发送到手表上。

final static String GROUP_KEY_EMAILS = "group_key_emails";

// Build the notification, setting the group appropriately
Notification notif = new NotificationCompat.Builder(mContext)
         .setContentTitle("New mail from " + sender1)
         .setContentText(subject1)
         .setSmallIcon(R.drawable.new_mail)
         .setGroup(GROUP_KEY_EMAILS)
         .build();

// Issue the notification
NotificationManagerCompat notificationManager =
        NotificationManagerCompat.from(this);
notificationManager.notify(notificationId1, notif);

Later on, when you create another notification, specify the same group key. When you call notify(), this notification appears in the same stack as the previous notification, instead of as a new card:

后边，当你创建令一个通知的时候，制定相同的group key，当你调用notify()方法的时候，这个通知将会出现在和前面的通知同样的堆中，而不是一个新的卡片。

Notification notif2 = new NotificationCompat.Builder(mContext)
         .setContentTitle("New mail from " + sender2)
         .setContentText(subject2)
         .setSmallIcon(R.drawable.new_mail)
         .setGroup(GROUP_KEY_EMAILS)
         .build();

notificationManager.notify(notificationId2, notif2);

By default, notifications appear in the order in which you added them, with the most recent notification visible at the top. You can order notifications in another fashion by calling setSortKey().

默认的情况下，通知是按照你添加它的顺序来显示的，最近的最新的通知显示在最上面。你可以通过setSortKey()方法来排序通知以另一种方式

Add a Summary Notification添加一个总结的通知

It's important that you still provide a summary notification that appears on handheld devices. So in addition to adding each unique notification to the same stack group, also add a summary notification and call setGroupSummary() on the summary notification.

对于手机端我们还是需要提供一个总结的通知。所以在为每一个独特的通知添加到相同的堆组之前，还是需要添加一个总结通知并且调用setGroupSummary()方法在总结通知中。

This notification does not appear in your stack of notifications on the wearable, but it appears as the only notification on the handheld device.

这个通知不会出现在你的额手表的通知堆中，但是这个会出现在手机设备上面作为唯一的通知。

Bitmap largeIcon = BitmapFactory.decodeResource(getResources(),
        R.drawable.ic_large_icon);

// Create an InboxStyle notification
Notification summaryNotification = new NotificationCompat.Builder(mContext)
        .setContentTitle("2 new messages")
        .setSmallIcon(R.drawable.ic_small_icon)
        .setLargeIcon(largeIcon)
        .setStyle(new NotificationCompat.InboxStyle()
                .addLine("Alex Faaborg   Check this out")                 .addLine("Jeff Chang   Launch Party")                 .setBigContentTitle("2 new messages")                 .setSummaryText("[email protected]"))
        .setGroup(GROUP_KEY_EMAILS)         .setGroupSummary(true)         .build();

notificationManager.notify(notificationId3, summaryNotification);

This notification uses NotificationCompat.InboxStyle, which gives you an easy way to create notifications for email or messaging apps. You can use this style, another one defined in NotificationCompat, or no style for the summary notification.

这个通知使 NotificationCompat.InboxStyle, 这个会给你简单的方式去你创建邮件和短信信息。你可以给summery notification 总结样式使用这个样式，或者在 NotificationCompat,里面的，或者不要任何的样式

Tip: To style the text like in the example screenshot, see Styling with HTML markup and Styling with Spannables.

提示为了让text的内容看上去和截图中一样,请查看 Styling with HTML markup 和Styling with Spannables.

Summary notifications can also affect notifications on wearables without being displayed on them. When creating a summary notification, you can use the NotificationCompat.WearableExtender class and callsetBackground() or addAction() to set a background image or an action that applies to the entire stack on the wearable. For instance, to set the background for an entire stack of notifications:

总结的通知也可以对手表端的通知产生作用 ，即使没有显示在他们上面。当创建总结通知的时候，你可以使用 NotificationCompat.WearableExtender 类并且调用setBackground（）和 addAction()去设置背景的图片或者一个action应用到整个堆到手表端。例如设置整个通知堆的背景。

Bitmap background = BitmapFactory.decodeResource(getResources(),
        R.drawable.ic_background);

NotificationCompat.WearableExtender wearableExtender =
        new NotificationCompat.WearableExtender()
        .setBackground(background);

// Create an InboxStyle notification
Notification summaryNotificationWithBackground =
        new NotificationCompat.Builder(mContext)
        .setContentTitle("2 new messages")
        ...
        .extend(wearableExtender)
        .setGroup(GROUP_KEY_EMAILS)
        .setGroupSummary(true)
        .build();

Next class: Creating Wearable Apps

Get news & tips