1 page.title=Updating Notifications 2 page.tags=notifications 3 helpoutsWidget=true 4 5 trainingnavtop=true 6 7 @jd:body 8 9 <div id="tb-wrapper"> 10 <div id="tb"> 11 12 <!-- table of contents --> 13 <h2>This lesson teaches you to</h2> 14 <ol> 15 <li><a href="#Updating">Modify a Notification</a></li> 16 <li><a href="#Removing">Remove Notifications</a></li> 17 </ol> 18 19 <!-- other docs (NOT javadocs) --> 20 <h2>You should also read</h2> 21 22 <ul> 23 <li> 24 <a href="{@docRoot}guide/topics/ui/notifiers/notifications.html">Notifications</a> API Guide 25 </li> 26 <li> 27 <a href="{@docRoot}guide/components/intents-filters.html"> 28 Intents and Intent Filters 29 </a> 30 </li> 31 <li> 32 <a href="https://material.google.com/patterns/notifications.html">Notifications</a> Design Guide 33 </li> 34 </ul> 35 36 37 </div> 38 </div> 39 <p> 40 When you need to issue a notification multiple times for the same type of event, you 41 should avoid making a completely new notification. Instead, you should consider updating a 42 previous notification, either by changing some of its values or by adding to it, or both. 43 </p> 44 45 <p> 46 The following section describes how to update notifications and also how to remove them. 47 </p> 48 <h2 id="Updating">Modify a Notification</h2> 49 <p> 50 To set up a notification so it can be updated, issue it with a notification ID by 51 calling {@link android.app.NotificationManager#notify(int, Notification) 52 NotificationManager.notify(ID, notification)}. To update this notification once you've issued 53 it, update or create a {@link android.support.v4.app.NotificationCompat.Builder} object, 54 build a {@link android.app.Notification} object from it, and issue the 55 {@link android.app.Notification} with the same ID you used previously. 56 </p> 57 <p> 58 The following snippet demonstrates a notification that is updated to reflect the 59 number of events that have occurred. It stacks the notification, showing a summary: 60 </p> 61 <pre> 62 mNotificationManager = 63 (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE); 64 // Sets an ID for the notification, so it can be updated 65 int notifyID = 1; 66 mNotifyBuilder = new NotificationCompat.Builder(this) 67 .setContentTitle("New Message") 68 .setContentText("You've received new messages.") 69 .setSmallIcon(R.drawable.ic_notify_status) 70 numMessages = 0; 71 // Start of a loop that processes data and then notifies the user 72 ... 73 mNotifyBuilder.setContentText(currentText) 74 .setNumber(++numMessages); 75 // Because the ID remains unchanged, the existing notification is 76 // updated. 77 mNotificationManager.notify( 78 notifyID, 79 mNotifyBuilder.build()); 80 ... 81 </pre> 82 83 <!-- ------------------------------------------------------------------------------------------ --> 84 <h2 id="Removing">Remove Notifications</h2> 85 <p> 86 Notifications remain visible until one of the following happens: 87 </p> 88 <ul> 89 <li> 90 The user dismisses the notification either individually or by using "Clear All" (if 91 the notification can be cleared). 92 </li> 93 <li> 94 The user touches the notification, and you called 95 {@link android.support.v4.app.NotificationCompat.Builder#setAutoCancel setAutoCancel()} when 96 you created the notification. 97 </li> 98 <li> 99 You call {@link android.app.NotificationManager#cancel(int) cancel()} for a specific 100 notification ID. This method also deletes ongoing notifications. 101 </li> 102 <li> 103 You call {@link android.app.NotificationManager#cancelAll() cancelAll()}, which removes 104 all of the notifications you previously issued. 105 </li> 106
