Action performed in android

How to add Extended Floating Action Button in Android | Android Studio | Java

How to add Extended Floating Action Button in Android | Android Studio | Java.

In this tutorial, we are going to create an extended floating action button in android. A floating action button (FAB) performs the primary, or most common, action on a screen. It appears in front of all screen content, typically as a circular shape with an icon in its center.

Extended Floating Action Button is the newly introduced class with Material Components library in Android.

Material Components is introduced with SDK 28 or Android P. It’s a superset of Support Design Library with lots of new additions and improvements. And, in this tutorial, we are going to create an extended floating action button.

So, let’s start creating the extended FAB.

Before going to create let’s see what you’re going to see.

Step 1: add the dependency

make sure to add the material design dependency in your build.gradle app file.

Step 2: add the drawable files

before going to design the main XML file, first, import the drawable files. Below drawable files that I used in my project.

Step 3: design the XML file

now, design the main XML file, add the Extended Floating Action Button that is set as the parent FAB and also add the child FAB. Here as a child FAB, I used two FABs.

parent FAB: Action

child FAB 1: Alarm

child FAB 2: Person

Step 4: add the functionality

now in the main JAVA file add the functionality for the extended FAB and add the click listener in the child FAB.

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ActionBar in Android with Example

In Android applications, ActionBar is the element present at the top of the activity screen. It is a salient feature of a mobile application that has a consistent presence over all its activities. It provides a visual structure to the app and contains some of the frequently used elements for the users. Android ActionBar was launched by Google in 2013 with the release of Android 3.0(API 11). Before that, the name of this top most visual element was AppBar. AppBar contains only the name of the application or current activity. It was not very much useful for the users and developers also have negligible option to customize it.

Google announced a support library along with the introduction of ActionBar. This library is a part of AppCompat and its purpose is to provide backward compatibility for older versions of Android and to support tabbed interfaces. All applications that use the default theme provided by the Android(Theme.AppCompat.Light.DarkActionBar), contains an ActionBar by default. However, developers can customize it in several ways depending upon their needs. Components included in the ActionBar are:

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• App Icon: Display the branding logo/icon of the application.
• View Controls: Section that displays the name of the application or current activity. Developers can also include spinner or tabbed navigation for switching between views.
• Action Button: Contains some important actions/elements of the app that may be required to the users frequently.
• Action Overflow: Include other actions that will be displayed as a menu.

Designing a Custom ActionBar

The following example demonstrates the steps involved in creating a custom ActionBar for the MainActivity of an application. All important aspects of visual elements like icon, title, subtitle, action buttons, and overflow menu will be covered.

Note: Following steps are performed on Android Studion version 4.0

Step 1: Default ActionBar

As mentioned earlier, every android app contains an ActionBar by default. This pre-included ActionBar display title for the current activity that is managed by the AncdroidManifest.xml file. The string value of the application’s title is provided by @string/app_name resource present under the application nodes.

Output:

Step 2: Creating a new directory and design items of ActionBar

To code the elements of ActionBar, create a new directory in the resource folder of the application project files. Right-click on the res folder and selects New -> Directory. Give the name “menu” to the new directory.

Further, create a new Menu Resource File by right click on the menu directory. As the ActionBar is being created for the main Activity, type the name as “main” to the Menu Resource File. With this, a new file named “main.xml” must be created under the menu directory. In this file, one can declare the items which will be displayed as the action buttons of the ActionBar.

For every menu items, the following attributes are needed to be configured:

• android:title: Its value contains the title of the menu item that will be displayed when a user clicks and holds that item in the app.
• android:id: A unique ID for the menu item that will be used to access it anywhere in the whole application files.
• android:orderInCategory: The value of this attribute specify the item’s position in the ActionBar. There are two ways to define the position of different menu items. The first one is to provide the same value of this attribute for all items and the position will be defined in the same order as they are declared in the code. The second way is to provide a different numeric value for all items and then the items will position themselves according to ascending order of this attribute’s value.
• app:showAsAction: This attribute defines how the item is going to be present in the action bar. There are four possible flags to choose from:
  • a. always: To display the item in the ActionBar all the time.
  • b. ifRoom: To keep the item if space is available.
  • c. never: With this flag, the item will be not be displayed as an icon in ActionBar, but will be present in the overflow menu.
  • d. withText: To represent an item as both icon and the title, one can append this flag with the always or ifRoom flag(always|withText or ifRoom|withText).
• android:icon: The icon of an item is referenced in the drawable directories through this attribute.

Icon of an ActionBar Item

In order to provide an icon to an item, right-click on the res folder, select new, and then Image Asset. A dialog box will appear, choose the Icon Type as Action Bar and Tab Icons. Choose assets type as “Clip Art” and select an image from the clip art collection. Provide a desired name to the icon. Click on Next, then Finish. This icon will now get loaded in the drawable directory of the res folder. The name provided by the developers to these icons will now be used to reference the item’s icon resource.

Below is the code to place a search icon, refresh icon, and an overflow menu in the ActionBar.

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Create a Notification

Notifications provide short, timely information about events in your app while it’s not in use. This page teaches you how to create a notification with various features for Android 4.0 (API level 14) and higher. For an introduction to how notifications appear on Android, see the Notifications Overview. For sample code that uses notifications, see the Android Notifications Sample.

Notice that the code on this page uses the NotificationCompat APIs from the Android support library. These APIs allow you to add features available only on newer versions of Android while still providing compatibility back to Android 4.0 (API level 14). However, some new features such as the inline reply action result in a no-op on older versions.

Add the support library

Although most projects created with Android Studio include the necessary dependencies to use NotificationCompat , you should verify that your module-level build.gradle file includes the following dependency:

Groovy

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Create a basic notification

A notification in its most basic and compact form (also known as collapsed form) displays an icon, a title, and a small amount of content text. In this section, you’ll learn how to create a notification that the user can click on to launch an activity in your app.

Figure 1. A notification with a title and text

For more details about each part of a notification, read about the notification anatomy.

Set the notification content

To get started, you need to set the notification’s content and channel using a NotificationCompat.Builder object. The following example shows how to create a notification with the following:

• A small icon, set by setSmallIcon() . This is the only user-visible content that’s required.
• A title, set by setContentTitle() .
• The body text, set by setContentText() .
• The notification priority, set by setPriority() . The priority determines how intrusive the notification should be on Android 7.1 and lower. (For Android 8.0 and higher, you must instead set the channel importance—shown in the next section.)

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Notice that the NotificationCompat.Builder constructor requires that you provide a channel ID. This is required for compatibility with Android 8.0 (API level 26) and higher, but is ignored by older versions.

By default, the notification’s text content is truncated to fit one line. If you want your notification to be longer, you can enable an expandable notification by adding a style template with setStyle() . For example, the following code creates a larger text area:

Kotlin

For more information about other large notification styles, including how to add an image and media playback controls, see Create a Notification with Expandable Detail.

Create a channel and set the importance

Before you can deliver the notification on Android 8.0 and higher, you must register your app’s notification channel with the system by passing an instance of NotificationChannel to createNotificationChannel() . So the following code is blocked by a condition on the SDK_INT version:

Kotlin

Because you must create the notification channel before posting any notifications on Android 8.0 and higher, you should execute this code as soon as your app starts. It’s safe to call this repeatedly because creating an existing notification channel performs no operation.

Notice that the NotificationChannel constructor requires an importance , using one of the constants from the NotificationManager class. This parameter determines how to interrupt the user for any notification that belongs to this channel—though you must also set the priority with setPriority() to support Android 7.1 and lower (as shown above).

Although you must set the notification importance/priority as shown here, the system does not guarantee the alert behavior you’ll get. In some cases the system might change the importance level based other factors, and the user can always redefine what the importance level is for a given channel.

For more information about what the different levels mean, read about notification importance levels.

Set the notification’s tap action

Every notification should respond to a tap, usually to open an activity in your app that corresponds to the notification. To do so, you must specify a content intent defined with a PendingIntent object and pass it to setContentIntent() .

The following snippet shows how to create a basic intent to open an activity when the user taps the notification:

Kotlin

Notice this code calls setAutoCancel() , which automatically removes the notification when the user taps it.

The setFlags() method shown above helps preserve the user’s expected navigation experience after they open your app via the notification. But whether you want to use that depends on what type of activity you’re starting, which may be one of the following:

• An activity that exists exclusively for responses to the notification. There’s no reason the user would navigate to this activity during normal app use, so the activity starts a new task instead of being added to your app’s existing task and back stack. This is the type of intent created in the sample above.
• An activity that exists in your app’s regular app flow. In this case, starting the activity should create a back stack so that the user’s expectations for the Back and Up buttons is preserved.

For more about the different ways to configure your notification’s intent, read Start an Activity from a Notification.

Show the notification

To make the notification appear, call NotificationManagerCompat.notify() , passing it a unique ID for the notification and the result of NotificationCompat.Builder.build() . For example:

Kotlin

Remember to save the notification ID that you pass to NotificationManagerCompat.notify() because you’ll need it later if you want to update or remove the notification.

Add action buttons

A notification can offer up to three action buttons that allow the user to respond quickly, such as snooze a reminder or even reply to a text message. But these action buttons should not duplicate the action performed when the user taps the notification.

Figure 2. A notification with one action button

To add an action button, pass a PendingIntent to the addAction() method. This is just like setting up the notification’s default tap action, except instead of launching an activity, you can do a variety of other things such as start a BroadcastReceiver that performs a job in the background so the action does not interrupt the app that’s already open.

For example, the following code shows how to send a broadcast to a specific receiver:

Kotlin

For more information about building a BroadcastReceiver to run background work, see the Broadcasts guide.

If you’re instead trying to build a notification with media playback buttons (such as to pause and skip tracks), see how to create a notification with media controls.

Add a direct reply action

The direct reply action, introduced in Android 7.0 (API level 24), allows users to enter text directly into the notification, which is delivered to your app without opening an activity. For example, you can use a direct reply action to let users reply to text messages or update task lists from within the notification.

Figure 3. Tapping the «Reply» button opens the text input

The direct reply action appears as an additional button in the notification that opens a text input. When the user finishes typing, the system attaches the text response to the intent you had specified for the notification action and sends the intent to your app.

Add the reply button

To create a notification action that supports direct reply:

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 text input. Later, your handheld app uses that key to retrieve the text of the input.

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Caution: If you re-use a PendingIntent , a user may reply to a different conversation than the one they thought they did. You must either provide a request code that is different for each conversation or provide an intent that doesn’t return true when you call equals() on the reply intent of any other conversation. The conversation ID is frequently passed as part of the intent’s extras bundle, but is ignored when you call equals() .

Attach the RemoteInput object to an action using addRemoteInput() .

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The system prompts the user to input a response when they trigger the notification action, as shown in figure 3.

Retrieve user input from the reply

To receive user input from the notification’s reply UI, call RemoteInput.getResultsFromIntent() , passing it the Intent received by your BroadcastReceiver :

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After you’ve processed the text, you must update the notification by calling NotificationManagerCompat.notify() with the same ID and tag (if used). This is necessary to hide direct reply UI and confirm to the user that their reply was received and processed correctly.

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When working with this new notification, use the context that’s passed to the receiver’s onReceive() method.

You should also append the reply to the bottom of the notification by calling setRemoteInputHistory() . However, if you’re building a messaging app, you should create a messaging-style notification and append the new message to the conversation.

For more advice for notifications from a messaging apps, see best practices for messaging apps.

Add a progress bar

Notifications can include an animated progress indicator that shows users the status of an ongoing operation.

Figure 4. The progress bar during and after the operation.

If you can estimate how much of the operation is complete at any time, use the «determinate» form of the indicator (as shown in figure 4) by calling setProgress(max, progress, false) . The first parameter is what the «complete» value is (such as 100); the second is how much is currently complete, and the last indicates this is a determinate progress bar.

As your operation proceeds, continuously call setProgress(max, progress, false) with an updated value for progress and re-issue the notification.

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At the end of the operation, progress should equal max . You can either leave the progress bar showing when the operation is done, or remove it. In either case, remember to update the notification text to show that the operation is complete. To remove the progress bar, call setProgress(0, 0, false) .

To display an indeterminate progress bar (a bar that does not indicate percentage complete), call setProgress(0, 0, true) . The result is an indicator that has the same style as the progress bar above, except the progress bar is a continuous animation that does not indicate completion. The progress animation runs until you call setProgress(0, 0, false) and then update the notification to remove the activity indicator.

Remember to change the notification text to indicate that the operation is complete.

Set a system-wide category

Android uses some pre-defined system-wide categories to determine whether to disturb the user with a given notification when the user has enabled Do Not Disturb mode.

If your notification falls into one of the pre-defined notification categories defined in NotificationCompat —such as CATEGORY_ALARM , CATEGORY_REMINDER , CATEGORY_EVENT , or CATEGORY_CALL —you should declare it as such by passing the appropriate category to setCategory() .

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This information about your notification category is used by the system to make decisions about displaying your notification when the device is in Do Not Disturb mode.

However, you are not required to set a system-wide category and should only do so if your notifications match one of the categories defined by in NotificationCompat .

Show an urgent message

Your app might need to display an urgent, time-sensitive message, such as an incoming phone call or a ringing alarm. In these situations, you can associate a full-screen intent with your notification. When the notification is invoked, users see one of the following, depending on the device’s lock status:

• If the user’s device is locked, a full-screen activity appears, covering the lockscreen.
• If the user’s device is unlocked, the notification appears in an expanded form that includes options for handling or dismissing the notification.

Caution: Notifications containing full-screen intents are substantially intrusive, so it’s important to use this type of notification only for the most urgent, time-sensitive messages. Note: If your app targets Android 10 (API level 29) or higher, you must request the USE_FULL_SCREEN_INTENT permission in your app’s manifest file in order for the system to launch the full-screen activity associated with the time-sensitive notification.

The following code snippet demonstrates how to associate your notification with a full-screen intent:

Kotlin

Set lock screen visibility

To control the level of detail visible in the notification from the lock screen, call setVisibility() and specify one of the following values:

• VISIBILITY_PUBLIC shows the notification’s full content.
• VISIBILITY_SECRET doesn’t show any part of this notification on the lock screen.
• VISIBILITY_PRIVATE shows basic information, such as the notification’s icon and the content title, but hides the notification’s full content.

When VISIBILITY_PRIVATE is set, you can also provide an alternate version of the notification content which hides certain details. For example, an SMS app might display a notification that shows You have 3 new text messages, but hides the message contents and senders. To provide this alternative notification, first create the alternative notification with NotificationCompat.Builder as usual. Then attach the alternative notification to the normal notification with setPublicVersion() .

However, the user always has final control over whether their notifications are visible on the lock screen and can even control that based on your app’s notification channels.

Update a notification

To update this notification after you’ve issued it, call NotificationManagerCompat.notify() again, passing it a notification with the same ID you used previously. If the previous notification has been dismissed, a new notification is created instead.

You can optionally call setOnlyAlertOnce() so your notification interupts the user (with sound, vibration, or visual clues) only the first time the notification appears and not for later updates.

Remove a notification

Notifications remain visible until one of the following happens:

• The user dismisses the notification.
• The user clicks the notification, and you called setAutoCancel() when you created the notification.
• You call cancel() for a specific notification ID. This method also deletes ongoing notifications.
• You call cancelAll() , which removes all of the notifications you previously issued.
• If you set a timeout when creating a notification using setTimeoutAfter() , the system cancels the notification after the specified duration elapses. If required, you can cancel a notification before the specified timeout duration elapses.

Best practices for messaging apps

Use the best practices listed here as a quick reference of what to keep in mind when creating notifications for your messaging and chat apps.

Use MessagingStyle

Starting in Android 7.0 (API level 24), Android provides a notification style template specifically for messaging content. Using the NotificationCompat.MessagingStyle class, you can change several of the labels displayed on the notification, including the conversation title, additional messages, and the content view for the notification.

The following code snippet demonstrates how to customize a notification’s style using the MessagingStyle class.

Kotlin

Starting in Android 8.0 (API level 26), notifications that use the NotificationCompat.MessagingStyle class display more content in their collapsed form. You can also use the addHistoricMessage() method to provide context to a conversation by adding historic messages to messaging-related notifications.

• Call MessagingStyle.setConversationTitle() to set a title for group chats with more than two people. A good conversation title might be the name of the group chat or, if it doesn’t have a specific name, a list of the participants in the conversation. Without this, the message may be mistaken as belonging to a one-to-one conversation with the sender of the most recent message in the conversation.
• Use the MessagingStyle.setData() method to include media messages such as images. MIME types, of the pattern image/* are currently supported.

Use direct reply

Direct Reply allows a user to reply inline to a message.

• After a user replies with the inline reply action, use MessagingStyle.addMessage() to update the MessagingStyle notification and do not retract or cancel the notification. Not cancelling the notification allows a user to send multiple replies from the notification.
• To make the inline reply action compatible with Wear OS, call Action.WearableExtender.setHintDisplayInlineAction(true) .
• Use the addHistoricMessage() method to provide context to a direct reply conversation by adding historic messages to the notification.

Enable smart reply

• To enable Smart Reply, call setAllowGeneratedResponses(true) on the reply action. This causes Smart Reply responses to be available to users when the notification is bridged to a Wear OS device. Smart Reply responses are generated by an entirely on-watch machine learning model using the context provided by the NotificationCompat.MessagingStyle notification, and no data is uploaded to the Internet to generate the responses.

Add notification metadata

• Assign notification metadata to tell the system how to handle your app notifications when the device is in Do Not Disturb mode. For example, use the addPerson() or setCategory(Notification.CATEGORY_MESSAGE) method to override the Do Not Disturb mode.

Content and code samples on this page are subject to the licenses described in the Content License. Java is a registered trademark of Oracle and/or its affiliates.

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