Android Notification

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1 Android Notification

2 Notification A notification is a message you can display to the user outside of your application's normal UI. appears as an icon in the notification area. the notification drawer shows details of the notification.

3 Notification Drawer Displays notifications

4 Creating a Notification You specify the UI information and actions for a notification in a NotificationCompat.Builder object. To create the notification itself, you call NotificationCompat.Builder.build() returns a Notification object. To issue the notification, you pass the Notification object to the system by calling NotificationManager.notify

5 Required notification contents A Notification object must contain the following: A small icon, set by setsmallicon() A title, set by setcontenttitle() Detail text, set by setcontenttext()

6 Notification actions An action allows users to go directly from the notification to an Activity. Inside a Notification, an action is defined by a PendingIntent which contains an Intent. The intent starts an Activity in your app. To associate PendingIntent with a gesture like touch/click, call an API of NotificationCompat.Builder object.

7 Notification Priority five priority levels, ranging from PRIORITY_MIN ( 2) to PRIORITY_MAX (2); if not set, the priority defaults to PRIORITY_DEFAULT (0). To set a notification's priority, call NotificationCompat.Builder.setPriority()

8 Preserving Navigation when Starting an Activity When you start an Activity from a notification, you must preserve the user's expected navigation experience. Clicking Back should take the user back through the application's normal work flow to the Home screen set up the PendingIntent to start a fresh task, and provide the PendingIntent with a back stack that reproduces the application's normal Back behavior

9 Example Notification NotificationCompat.Builder mbuilder = new NotificationCompat.Builder(this).setSmallIcon(R.drawable.notification_icon).setContentTitle("My notification").setcontenttext("hello World!"); // Creates an explicit intent for an Activity in your app Intent resultintent = new Intent(this, ResultActivity.class);

10 // The stack builder object will contain an artificial back stac // started Activity. // This ensures that navigating backward from the Activity le // your application to the Home screen. TaskStackBuilder stackbuilder = TaskStackBuilder.create(this // Adds the back stack for the Intent (but not the Intent itse stackbuilder.addparentstack(resultactivity.class); // Adds the Intent that starts the Activity to the top of the s stackbuilder.addnextintent(resultintent); PendingIntent resultpendingintent = stackbuilder.getpendingintent( 0, PendingIntent.FLAG_UPDATE_CURRENT );

11 mbuilder.setcontentintent(resultpendingintent); NotificationManager mnotificationmanager = (NotificationManager) getsystemservice (Context.NOTIFICATION_SERVICE); // mid allows you to update the notification later on. mnotificationmanager.notify(mid, mbuilder.build());

12 Toast Notification A toast notification is a message that pops up on the surface of the window. A toast provides simple feedback about an operation in a small popup. It only fills the amount of space required for the message and the user's current activity remains visible and interactive. The notification automatically fades in and out, and does not accept interaction events. Because a toast can be created from a background Service, it appears even if the application isn't visible.

13 Toast Message Context context = getapplicationcontext(); CharSequence text = "Hello toast!"; int duration = Toast.LENGTH_SHORT; Toast toast = Toast.makeText(context, text, duration); toast.show();

14 Positioning your Toast A standard toast notification appears near the bottom of the screen, centered horizontally. change this position with the setgravity(int, int, int), gravity constant, x-offset, y-offset toast.setgravity(gravity.top Gravity.LEFT, 0, 0);

15 Creating a Custom Toast View If a simple text message isn't enough, you can create a customized layout for your toast notification define a View layout, in XML or in your application code, and pass the root View object to setview(view) method.

16 toast_layout.xml <LinearLayout xmlns:android= " android:orientation="horizontal" android:layout_width="fill_parent" android:layout_height="fill_parent" android:padding="8dp" android:background="#daaa" >

17 <ImageView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginright="8dp" /> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:textcolor="#fff" /> </LinearLayout>

18 Inflating an XML Toast View LayoutInflater inflater = getlayoutinflater(); View layout = inflater.inflate(r.layout.custom_toast, (ViewGroup) findviewbyid(r.id.toast_layout_root)); TextView text = (TextView) layout.findviewbyid(r.id.text); text.settext("this is a custom toast"); Toast toast = new Toast(getApplicationContext()); toast.setgravity(gravity.center_vertical, 0, 0); toast.setduration(toast.length_long); toast.setview(layout); toast.show();

Lecture 14. Android Application Development

Lecture 14. Android Application Development Lecture 14 Android Application Development Notification Instructor Muhammad Owais muhammad.owais@riphah.edu.pk Cell: 03215500223 Notifications Used to notify user for events Three general forms of Notifications