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A notification is a message that Android displays outside your app'southward UI to provide the user with reminders, communication from other people, or other timely information from your app. Users tin tap the notification to open your app or accept an action directly from the notification.

This page provides an overview of where notifications appear and the available features. If you desire to start edifice your notifications, instead read Create a Notification.

For more data about the design and interaction patterns, see the Notifications design guide. Additionally, run across the Android Notifications Sample for a demonstration of best practices in using the Notification.Way API in both mobile and wearable apps.

Appearances on a device

Notifications appear to users in different locations and formats, such as an icon in the status bar, a more detailed entry in the notification drawer, every bit a bluecoat on the app'south icon, and on paired wearables automatically.

Condition bar and notification drawer

When you lot issue a notification, it outset appears as an icon in the status bar.

Figure i. Notification icons appear on the left side of the status bar

Users tin swipe downwards on the condition bar to open up the notification drawer, where they can view more details and accept actions with the notification.

Figure 2. Notifications in the notification drawer

Users can drag downwards on a notification in the drawer to reveal the expanded view, which shows additional content and activity buttons, if provided.

A notification remains visible in the notification drawer until dismissed by the app or the user.

Heads-up notification

Commencement with Android v.0, notifications can briefly appear in a floating window called a heads-upwardly notification. This beliefs is normally for important notifications that the user should know about immediately, and it appears simply if the device is unlocked.

Effigy 3. A heads-up notification appears in front of the foreground app

The heads-upward notification appears the moment your app issues the notification and it disappears after a moment, merely remains visible in the notification drawer equally usual.

Example conditions that might trigger heads-up notifications include the following:

The user'due south activity is in fullscreen fashion (the app uses fullScreenIntent).
The notification has high priority and uses ringtones or vibrations on devices running Android vii.1 (API level 25) and lower.
The notification channel has high importance on devices running Android 8.0 (API level 26) and higher.

Lock screen

Starting time with Android 5.0, notifications can announced on the lock screen.

Yous can programmatically set the level of item visible in notifications posted by your app on a secure lock screen, or fifty-fifty whether the notification will prove on the lock screen at all.

Users can use the system settings to cull the level of detail visible in lock screen notifications, including the option to disable all lock screen notifications. Starting with Android viii.0, users tin can choose to disable or enable lock screen notifications for each notification channel.

Effigy 4. Notifications on the lock screen with sensitive content hidden

To acquire more, encounter how to Set lock screen visibility.

App icon badge

In supported launchers on devices running Android eight.0 (API level 26) and higher, app icons indicate new notifications with a colored "badge" (also known as a "notification dot") on the corresponding app launcher icon.

Users tin can long-press on an app icon to see the notifications for that app. Users can and so dismiss or act on notifications from that menu, similar to the notification drawer.

Figure five. Notification badges and the long-press menu

To learn more than about how badges piece of work, read Notification badges.

Vesture OS devices

If the user has a paired Wear Bone device, all your notifications appear there automatically, including expandable particular and activeness buttons.

You can likewise heighten the experience past customizing some appearances for the notification on wearables and provide different actions, including suggested replies and voice input replies. For more information, see how to add wearable-specific features to your notification.

Figure 6. Notifications automatically appear on a paired Wear Os device

Notification anatomy

The design of a notification is determined by arrangement templates—your app simply defines the contents for each portion of the template. Some details of the notification appear merely in the expanded view.

Figure seven. A notification with bones details

The most common parts of a notification are indicated in effigy vii as follows:

Modest icon: This is required and gear up with setSmallIcon().
App proper name: This is provided by the organization.
Time stamp: This is provided by the system but you can override with setWhen() or hide information technology with setShowWhen(false).
Large icon: This is optional (usually used only for contact photos; do non use it for your app icon) and set with setLargeIcon().
Title: This is optional and set with setContentTitle().
Text: This is optional and ready with setContentText().

We strongly recommend using organisation templates to ensure proper design compatibility on all devices. If necessary, however, you can create a custom notification layout.

For more than data about how to create a notification with these features and more than, read Create a Notification.

Notification actions

Although it'southward not required, every notification should open an appropriate app activity when tapped. In improver to this default notification action, you can add action buttons that consummate an app-related job from the notification (often without opening an action), as shown in effigy 9.

Figure 9. A notification with action buttons

Starting in Android 7.0 (API level 24), you can as well add together an action to answer to messages or enter other text direct from the notification.

Starting in Android 10 (API level 29), the platform can automatically generate activity buttons with suggested intent-based deportment.

Calculation action buttons is explained further in Create a Notification.

Require an unlocked device

Users might encounter notification actions on the device'south lock screen. If a given notification activity causes an app to launch an activity or ship a directly reply, users must unlock the device earlier the app can invoke that notification action.

On Android 12 (API level 31) and college, you tin configure a notification action such that the device must be unlocked in order for your app to invoke that action, no matter what workflow the activeness launches. This option helps add an extra layer of security to notifications on locked devices.

To crave a device to exist unlocked before your app invokes a given notification activeness, pass true into setAuthenticationRequired() when creating your notification activeness, as shown in the following code snippet:

Kotlin

val moreSecureNotification = Notification.Builder(         context, NotificationListenerVerifierActivity.TAG)     .addAction(...)              // This notification always requests hallmark when invoked     // from a lock screen.     .setAuthenticationRequired(truthful)              .build()

Coffee

Notification moreSecureNotification = new Notification.Architect(         context, NotificationListenerVerifierActivity.TAG)     .addAction(...)              // This notification always requests hallmark when invoked     // from a lock screen.     .setAuthenticationRequired(truthful)              .build();

Expandable notification

By default, the notification'southward text content is truncated to fit on one line. If you want your notification to exist longer, you lot can enable a larger text area that's expandable by applying an additional template, as shown in figure viii.

Figure 8. An expandable notification for big text

You can also create an expandable notification with an image, in inbox style, a conversation conversation, or media playback controls. For more information, read Create an Expandable Notification.

Notification updates and groups

To avert bombarding your users with multiple or redundant notifications when you accept additional updates, yous should consider updating an existing notification rather than issuing a new one, or consider using the inbox-style notification to show conversation updates.

However, if it's necessary to deliver multiple notifications, you should consider group those dissever notifications into a group (available on Android 7.0 and higher). A notification grouping allows you to collapse multiple notifications into merely one post in the notification drawer, with a summary. The user can then expand the notification to reveal the details for each individual notification.

The user can progressively expand the notification grouping and each notification within it for more details.

Figure 10. A collapsed and expanded notification group

To learn how to add notifications to a grouping, see Create a Group of Notifications.

Notification channels

Starting in Android viii.0 (API level 26), all notifications must be assigned to a channel or information technology will non appear. By categorizing notifications into channels, users can disable specific notification channels for your app (instead of disabling all your notifications), and users tin control the visual and auditory options for each channel—all from the Android system settings (figure 11). Users tin as well long-printing a notification to alter behaviors for the associated channel.

On devices running Android 7.one (API level 25) and lower, users can manage notifications on a per-app basis only (effectively each app just has ane channel on Android 7.i and lower).

Figure 11. Notification settings for Clock app and one of its channels

I app tin can take multiple notification channels—a separate channel for each type of notification the app issues. An app can likewise create notification channels in response to choices made by users of your app. For example, you may set upwards carve up notification channels for each conversation group created by a user in a messaging app.

The channel is also where you specify the importance level for your notifications on Android 8.0 and higher. So all notifications posted to the same notification channel have the same behavior.

For more than information, run into Create and Manage Notification Channels.

Notification importance

Android uses the importance of a notification to determine how much the notification should interrupt the user (visually and audibly). The higher the importance of a notification, the more interruptive the notification will be.

On Android 8.0 (API level 26) and above, importance of a notification is determined past the importance of the channel the notification was posted to. Users tin can change the importance of a notification channel in the organization settings (figure 12). On Android 7.i (API level 25) and below, importance of each notification is determined by the notification's priority.

Effigy 12. Users tin can change the importance of each channel on Android 8.0 and higher

The possible importance levels are the following:

Urgent: Makes a sound and appears as a heads-up notification.
High: Makes a sound.
Medium: No audio.
Depression: No sound and does not appear in the status bar.

All notifications, regardless of importance, appear in not-interruptive system UI locations, such equally in the notification drawer and as a badge on the launcher icon (though you tin can change the appearance of the notification badge).

For more information, encounter how to prepare the importance.

Do Not Disturb mode

Starting in Android five.0 (API level 21), users can enable Do Not Disturb fashion, which silences sounds and vibration for all notifications. Notifications still appear in the system UI as normal, unless the user specifies otherwise.

There are 3 dissimilar levels bachelor in Practice Not Disturb way:

Total silence: blocks all sounds and vibrations, including from alarms, music, videos, and games.
Alarms just: blocks all sounds and vibrations, except from alarms.
Priority merely: users tin can configure which organization-broad categories can interrupt them (such as merely alarms, reminders, events, calls, or messages). For letters and calls, users tin can likewise choose to filter based on who the sender or caller is (effigy 13).

Figure 13. Users can can allow notifications through based on system-wide categories (left) and based on who sent a message or who is calling (correct).

On Android 8.0 (API level 26) and above, users can additionally allow notifications through for app-specific categories (also known as channels) by overriding Do Not Disturb on a channel-by-channel basis. For case, a payment app might accept channels for notifications related to withdrawals and deposits. The user can then choose to allow either withdrawal notifications, deposit notifications, or both when in priority mode. On devices running Android 7.one (API level 25) and beneath, users tin allow notifications through on an app by app basis, rather than on a channel past aqueduct ground.

To properly configure your notifications for these user settings, you must set a system-wide category and channel.

Notifications for foreground services

A notification is required when your app is running a "foreground service"—a Service running in the background that'southward long living and noticeable to the user, such every bit a media player. This notification cannot be dismissed like other notifications. To remove the notification, the service must exist either stopped or removed from the "foreground" state.

For more information read Running a service in the foreground. And if you are building a media player, likewise read Using MediaStyle notifications with a foreground service.

Posting limits

Beginning with Android viii.1 (API level 27), apps cannot make a notification audio more than once per second. If your app posts multiple notifications in ane second, they all announced as expected, but only the first notification per 2d makes a audio.

Nevertheless, Android also applies a rate limit when updating a notification. If you post updates to a single notification too frequently (many in less than one 2nd), the arrangement might drop some updates.

Notification compatibility

Since Android 1.0, the notification organization UI and the notification-related APIs have continually evolved. To use the latest notification API features while nevertheless supporting older devices, use the back up library notification API: NotificationCompat and its subclasses, likewise equally NotificationManagerCompat. This will allow you to avert writing conditional code to check API levels considering these APIs handle that for you.

NotificationCompat is updated as the platform evolves to include the latest methods. It is important to note that the availability of a method in NotificationCompat does not guarantee that the corresponding feature will be provided on older devices. In some cases calling a newly-introduced API results in a no-op on older devices. For example, NotificationCompat.addAction() displays the activity push on a device running Android four.i (API level 16) and college only.

The following is a summary of the near notable behavior changes for Android notifications.

Android 4.1, API level 16

Introduced expandable notification templates (called notification styles), allowing for larger notification content area to display information. Users tin can use a one finger swipe up/down gesture to aggrandize a notification.
Also introduced the ability to add boosted actions, in the form of buttons, to a notification.
Added power for users to turn notifications off on a per-app basis in settings.

Android 4.4, API level xix and twenty

Notification listener services were added to the API.
Android Wear (now called Wear Bone) back up was added in API level twenty.

Android 5.0, API level 21

Introduced lock screen and heads-up notifications.
The user tin now put the phone into Do Not Disturb manner and configure which notifications are allowed to interrupt them when the device is in priority simply manner.
Methods added to API set whether or not a notification is displayed on the lock screen (setVisibility()) and for specifying "public" version of the notification text.
setPriority() method added which tells the arrangement how "interruptive" this notification should be (e.k. setting it to high makes the notification appear as a heads-upwardly notification).
Notification stacks back up added to Android Wear (at present called Wear OS) devices. Put notifications into a stack using setGroup(). Note that notification stacks were non supported on tablets nor phones yet. Notification stacks would later go known as a group or packet.

Android 7.0, API level 24

Notification templates were restyled to put emphasis on the hero image and avatar.
Iii notification templates were added: ane for messaging apps and the other two for decorating custom content views with the expandable affordance and other organisation decorations.
Back up added to handheld devices (phones and tablets) for notification groups. Uses the same API as Android Wear (now chosen Wear OS) notification stacks introduced in Android v.0 (API level 21).
Users can reply directly inside of a notification (they can enter text which will and so exist routed to the notification's parent app) using inline reply.

Android eight.0, API level 26

Individual notifications must now be put in a specific channel.
Users tin can now turn off notifications per channel, instead of turning off all notifications from an app.
Apps with active notifications display a notification "badge" on top of their app icon on the dwelling house/launcher screen.
Users can at present snooze a notification from the drawer. You tin can prepare an automatic timeout for a notification.
You lot can as well set the notification's background colour.
Some APIs regarding notification behaviors were moved from Notification to NotificationChannel. For case, use NotificationChannel.setImportance() instead of NotificationCompat.Builder.setPriority() for Android 8.0 and higher.

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Source: https://developer.android.com/guide/topics/ui/notifiers/notifications