Make notifications optional
Users should always be in control of notifications. Allow the user to disable your app's notifications or change their alert properties, such as alert sound and whether to use vibration, by adding a notification settings item to your application settings.
When to display a notification
To create an application that people enjoy using, it's important to recognize that the user's attention and focus is a resource that must be protected. While Android's notification system has been designed to minimize the impact of notifications on the user's attention, it is nonetheless still important to be aware of the fact that notifications are interrupting the user's task flow. As you plan your notifications, ask yourself if they are important enough to warrant an interruption. If you are unsure, allow the user to opt into a notification using your apps notification settings or adjust the notifications priority flag to LOW or MIN to avoid distracting the user while they are doing something else.
While well behaved apps generally only speak when spoken to, there are some limited cases where an app actually should interrupt the user with an unprompted notification.
Notifications should be used primarily for time sensitive events, and especially if these synchronous events involve other people. For instance, an incoming chat is a real time and synchronous form of communication: there is another user actively waiting on you to respond. Calendar events are another good example of when to use a notification and grab the user's attention, because the event is imminent, and calendar events often involve other people.
Interacting With Notifications
Notifications are indicated by icons in the status bar and can be accessed by opening the notification drawer.
Touching a notification opens the associated app to detailed content matching the notification. Swiping left or right on a notification removes it from the list.
Ongoing notifications
Ongoing notifications keep users informed about an ongoing process in the background. For example, music players announce the currently playing track in the notification system and continue to do so until the user stops the playback. They can also be used to show the user feedback for longer tasks like downloading a file, or encoding a video. Ongoing notifications cannot be manually removed from the notification drawer.
The L lockscreen doesn't show transport controls for RCC (Remote Control Client)s anymore. But the lockscreen does how notifications, so each app's playback notification is now the primary way for users to control playback from a locked state. This gives apps more control over which buttons to show and in what way, while providing a consistent experience for the user whether on the lockscreen or unlocked.
Dialogs and toasts are for feedback not notifications
Your app should not create a dialog or toast if it is not currently on screen. Dialogs and Toasts should only be displayed as the immediate response to the user taking an action inside of your app. For further guidance on the use of dialogs and toasts, refer to Confirming & Acknowledging.
Ranking and Ordering
Notifications are "news" and so they are essentially shown in reverse-chronological order, with special consideration given to the app's stated notification priority.
In L, notifications are now a key part of the lockscreen, and are featured prominently every time the device display comes on. Because space on the lockscreen is tight, it is more important than ever to identify the most urgent or relevant notifications.
原文的翻译翻译的资料。通知的设计
通知系统允许用户保持呗通知的状态，在你的App中有最近相关的时间消息，例如从一个朋友或者一个日历事件的提醒的一个新的聊天信息。将通知当作一个新闻频道，它能在重要事件发生的时候或者一个用户不注意的用户事件发生时提醒用户，适当同步于所有的Android设备。论文网 Android通知的设计英文文献和中文翻译(2):http://www.youerw.com/fanyi/lunwen_41699.html