Notification uses full resolution

1、 effect

 

 

2、 brief introduction

Notice is Android In your app UI Messages displayed outside , Used to provide reminders to users 、 Communications from others or other timely information from your app . Users can click the notification to open your application or directly perform actions from the notification .

2.1、 Exhibition

• Notifications are displayed to users in different locations and formats , For example, the icon in the status bar 、 Notify more detailed entries in the drawer 、 Badges on app icons and wearable devices that are automatically paired .
• When notice is given , It first appears as an icon in the status bar .

2.2、 operation

• Users can slide down the status bar to open the notification drawer , There they can view more details and take action based on the notification .
• The user can drag down the notification in the drawer to display the expanded view , This view shows other content and action buttons （ Provided ）.
• Notices remain visible in the notice drawer , Until it is closed by the application or user .

3、 Functional disassembly

This article will lead you through the implementation of various common notification functions , And each Android What the version needs to do adapter .

4、 Function realization

4.0、 The key class

1. NotificationManager Notification manager , Used to initiate 、 to update 、 Delete notification
2. NotificationChannel Notification channels ,8.0 And above to configure channels and priorities
3. NotificationCompat.Builder Notify the constructor , It is used to configure the layout display of notifications and related operations

Commonly used API, Look at the first 5 section . Each version fits , Look at the first 6 section .

4.1、 General notice

private fun createNotificationForNormal() {
        //  adapter 8.0 And above   Create channels 
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            val channel = NotificationChannel(mNormalChannelId, mNormalChannelName, NotificationManager.IMPORTANCE_LOW).apply {
                description = " describe "
                setShowBadge(false) //  Whether to display corner marks on the desktop 
            }
            mManager.createNotificationChannel(channel)
        }
        //  Click intent  // setDeleteIntent  Remove intent 
        val intent = Intent(this, MaterialButtonActivity::class.java)
        val pendingIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_IMMUTABLE)
        //  Building configuration 
        mBuilder = NotificationCompat.Builder([email protected], mNormalChannelId)
            .setContentTitle(" General notice ") //  title 
            .setContentText(" General notice content ") //  Text 
            .setSmallIcon(R.mipmap.ic_launcher) //  Small icons 
            .setLargeIcon(BitmapFactory.decodeResource(resources, R.mipmap.ic_avatar)) //  Large icon 
            .setPriority(NotificationCompat.PRIORITY_DEFAULT) // 7.0  set priority 
            .setContentIntent(pendingIntent) //  Jump configuration 
            .setAutoCancel(true) //  Whether to disappear automatically （ Click on ）or mManager.cancel(mNormalNotificationId)、cancelAll、setTimeoutAfter()
        //  Initiation notice 
        mManager.notify(mNormalNotificationId, mBuilder.build())
    }

Several elements of initiating a general notification ：

• setContentTitle title
• setContentText Content
• setSmallIcon Small icons
• setLargeIcon Large icon
• setPriority priority or Importance （7.0 and 8.0 In different ways ）
• setContentIntent Click intent
• setAutoCancel Whether to cancel automatically
• notify Initiation notice

4.2、 Important notice

Important notice , The priority setting is the highest , Will be displayed directly on the screen （ The front desk ）, Not just the notice drawer , So be sure to cautious Set up , Do not cause negative emotions of users .

    private fun createNotificationForHigh() {
        val intent = Intent(this, MaterialButtonActivity::class.java)
        val pendingIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_IMMUTABLE)
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            val channel = NotificationChannel(mHighChannelId, mHighChannelName, NotificationManager.IMPORTANCE_HIGH)
            channel.setShowBadge(true)
            mManager.createNotificationChannel(channel)
        }
        mBuilder = NotificationCompat.Builder([email protected], mHighChannelId)
            .setContentTitle(" Important notice ")
            .setContentText(" Important notice contents ")
            .setSmallIcon(R.mipmap.ic_launcher)
            .setLargeIcon(BitmapFactory.decodeResource(resources, R.mipmap.ic_avatar))
            .setAutoCancel(true)
            .setNumber(999) //  Customize the number of desktop notifications 
            .addAction(R.mipmap.ic_avatar, " Go to see ", pendingIntent)//  Actions on notifications 
            .setCategory(NotificationCompat.CATEGORY_MESSAGE) //  Notification category ," Don't disturb mode " The system will decide whether to display your notification 
            .setVisibility(NotificationCompat.VISIBILITY_PRIVATE) //  Screen visibility , When the screen is locked , Show icon And the title , Content hiding 
        mManager.notify(mHighNotificationId, mBuilder.build())
    }

Here are a few new configurations ：

• setNumber Number of desktop notifications
• addAction Actions on notifications
• setCategory Notification category ," Don't disturb mode " The system will decide whether to display your notification
• setVisibility Screen visibility , When the screen is locked , Show icon And the title , Content hiding , Unlock to view all

4.2.1、 Actions on notifications

Can pass addAction Add a custom action to the notification , Pictured above ： Go to see .

Can pass PendingIntent Open one Activity, You can also send a broadcast .

stay Android10.0 And above , The system will also recognize and add some operations by default , For example, on the SMS notification 「 Copy verification code 」.

4.2.2、 Importance level

• emergency ： Sound and display as a reminder notification
• high ： Make a sound
• in ： No sound
• low ： No sound and does not appear in the status bar

4.3、 Progress bar notification

 

  private fun createNotificationForProgress() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            val channel = NotificationChannel(mProgressChannelId, mProgressChannelName, NotificationManager.IMPORTANCE_DEFAULT)
            mManager.createNotificationChannel(channel)
        }
        val progressMax = 100
        val progressCurrent = 30
        mBuilder = NotificationCompat.Builder([email protected], mProgressChannelId)
            .setContentTitle(" Progress notification ")
            .setContentText(" In the download ：$progressCurrent%")
            .setSmallIcon(R.mipmap.ic_launcher)
            .setLargeIcon(BitmapFactory.decodeResource(resources, R.mipmap.ic_avatar))
            //  The first 3 Parameters indeterminate,false Indicates the determined progress , such as 100,true Indicates an uncertain progress , Progress animation will always be displayed , Until the update status download is complete , Or delete the notification 
            .setProgress(progressMax, progressCurrent, false)

        mManager.notify(mProgressNotificationId, mBuilder.build())
    }

The most common is the download progress , For example, in app version update .

adopt setProgress Configuration progress , receive 3 Parameters ：

• max Maximum
• progress Current progress
• indeterminate false Indicates the determined progress , such as 100,true Indicates an uncertain progress , Progress animation will always be displayed , Until the update status is complete , Or delete the notification

How to update progress and look down .

4.4、 Update progress bar notifications

   private fun updateNotificationForProgress() {
        if (::mBuilder.isInitialized) {
            val progressMax = 100
            val progressCurrent = 50
            // 1. Update progress 
            mBuilder.setContentText(" In the download ：$progressCurrent%").setProgress(progressMax, progressCurrent, false)
            // 2. Download complete 
            //mBuilder.setContentText(" Download complete ！").setProgress(0, 0, false)
            mManager.notify(mProgressNotificationId, mBuilder.build())
            Toast.makeText(this, " Updated progress to $progressCurrent%", Toast.LENGTH_SHORT).show()
        } else {
            Toast.makeText(this, " Please send a progress bar notice first ", Toast.LENGTH_SHORT).show()
        }
    }

The update progress is also through setProgress, Modify the current progress value .

There are two types of updates ：

1. Update progress ： Modify the progress value
2. Download complete ： Both the total progress and the current progress are set to 0 that will do , Also update the copy

Be careful ： If there are multiple progress notifications , How to update to the specified notification , It's through NotificationId Matching .

Author：yechaoa

4.5、 Large text notification

  private fun createNotificationForBigText() {
        val bigText =
            "A notification is a message that Android displays outside your app's UI to provide the user with reminders, communication from other people, or other timely information from your app. Users can tap the notification to open your app or take an action directly from the notification."
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            val channel = NotificationChannel(mBigTextChannelId, mBigTextChannelName, NotificationManager.IMPORTANCE_DEFAULT)
            mManager.createNotificationChannel(channel)
        }
        mBuilder = NotificationCompat.Builder([email protected], mBigTextChannelId)
            .setContentTitle(" Large text notification ")
            .setStyle(NotificationCompat.BigTextStyle().bigText(bigText))
            .setSmallIcon(R.mipmap.ic_launcher)
            .setLargeIcon(BitmapFactory.decodeResource(resources, R.mipmap.ic_avatar))
            .setAutoCancel(true)
        mManager.notify(mBigTextNotificationId, mBuilder.build())
    }

• setStyle(NotificationCompat.BigTextStyle().bigText(bigText))

By default, a maximum of one line is displayed for the notification content , Excess will be cropped , And cannot be expanded , The experience of content disclosure is very bad , The displayed content may not attract users to click to view , So there is also a large text notification ,

Once and for all, no matter how many lines of content , Are notified in large text , The specific display allows the system to adapt itself .

4.6、 Large picture notification

    private fun createNotificationForBigImage() {
        val bigPic = BitmapFactory.decodeResource(resources, R.drawable.ic_big_pic)
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            val channel = NotificationChannel(mBigImageChannelId, mBigImageChannelName, NotificationManager.IMPORTANCE_DEFAULT)
            mManager.createNotificationChannel(channel)
        }
        mBuilder = NotificationCompat.Builder([email protected], mBigImageChannelId)
            .setContentTitle(" Large picture notification ")
            .setContentText(" There are beauties , Expand and see ")
            .setStyle(NotificationCompat.BigPictureStyle().bigPicture(bigPic))
            .setSmallIcon(R.mipmap.ic_launcher)
            .setLargeIcon(BitmapFactory.decodeResource(resources, R.mipmap.ic_avatar))
            .setAutoCancel(true)
        mManager.notify(mBigImageNotificationId, mBuilder.build())
    }

Similar to large text notification

• setStyle(NotificationCompat.BigPictureStyle().bigPicture(bigPic))

There is a point of attention , When there are multiple notifications , The default is merged , It is not unfolded , So you can go through setContentText(" There are beauties , Expand and see ") Add a hint .

• Currently applied notifications do not exceed 3 strip , It will unfold
• exceed 3 strip , Notifications aggregate and collapse

4.7、 Custom notifications

    private fun createNotificationForCustom() {
        //  adapter 8.0 And above 
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            val channel = NotificationChannel(mCustomChannelId, mCustomChannelName, NotificationManager.IMPORTANCE_DEFAULT)
            mManager.createNotificationChannel(channel)
        }

        //  adapter 12.0 And above 
        mFlag = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
            PendingIntent.FLAG_IMMUTABLE
        } else {
            PendingIntent.FLAG_UPDATE_CURRENT
        }

        //  Add custom notifications view
        val views = RemoteViews(packageName, R.layout.layout_notification)

        //  Add pause resume event 
        val intentStop = Intent(mStopAction)
        val pendingIntentStop = PendingIntent.getBroadcast([email protected], 0, intentStop, mFlag)
        views.setOnClickPendingIntent(R.id.btn_stop, pendingIntentStop)

        //  Add completion event 
        val intentDone = Intent(mDoneAction)
        val pendingIntentDone = PendingIntent.getBroadcast([email protected], 0, intentDone, mFlag)
        views.setOnClickPendingIntent(R.id.btn_done, pendingIntentDone)

        //  establish Builder
        mBuilder = NotificationCompat.Builder([email protected], mCustomChannelId)
            .setSmallIcon(R.mipmap.ic_launcher)
            .setLargeIcon(BitmapFactory.decodeResource(resources, R.mipmap.ic_avatar))
            .setAutoCancel(true)
            .setCustomContentView(views)
            .setCustomBigContentView(views)//  Set custom notifications view

        //  Initiation notice 
        mManager.notify(mCustomNotificationId, mBuilder.build())
    }

If it is a front desk notification of a player , The default layout display does not meet the requirements , Then you will use the custom layout .

adopt RemoteViews Building custom layouts view. because RemoteViews It's not a real view, It's just a view Description of , Therefore, the event processing still needs the help of PendingIntent.

• setCustomContentView The default layout displays , That is, the layout in the folded state
• setCustomBigContentView Layout in expanded state

In folded state , It may show some basic information , Take the player for example , For example, the name of the current song 、 singer 、 Pause 、 continue 、 Next, wait , It's almost impossible to show . In the expanded state , Can provide more information , Such as album information , Singer information, etc

The default layout height in these two states ：

• Collapse view layout ,48dp
• Expand view layout ,252dp

4.8、 Update custom notifications

    private fun updateNotificationForCustom() {
        //  Sending notice   Update status and UI
        sendBroadcast(Intent(mStopAction))
    }

    private fun updateCustomView() {
        val views = RemoteViews(packageName, R.layout.layout_notification)
        val intentUpdate = Intent(mStopAction)
        val pendingIntentUpdate = PendingIntent.getBroadcast(this, 0, intentUpdate, mFlag)
        views.setOnClickPendingIntent(R.id.btn_stop, pendingIntentUpdate)
        //  Update based on status UI
        if (mIsStop) {
            views.setTextViewText(R.id.tv_status, " Those dreams that you are very adventurous - Stop playing ")
            views.setTextViewText(R.id.btn_stop, " continue ")
            mBinding.mbUpdateCustom.text = " continue "
        } else {
            views.setTextViewText(R.id.tv_status, " Those dreams that you are very adventurous - Playing ")
            views.setTextViewText(R.id.btn_stop, " Pause ")
            mBinding.mbUpdateCustom.text = " Pause "
        }

        mBuilder.setCustomContentView(views).setCustomBigContentView(views)
        //  Reissue notification updates UI, Be careful ： It must be the same notice id, namely mCustomNotificationId
        mManager.notify(mCustomNotificationId, mBuilder.build())
    }

above-mentioned , because RemoteViews Not directly view, So you can go through radio broadcast The way , Reset the build configuration of this notification , To achieve the effect of updating .

In ancient times v4 There is also... In the bag MediaStyle,AndroidX It has fallen .

5、 Commonly used API

API	describe
setContentTitle	title
setContentText	Content
setSubText	Subtitle
setLargeIcon	Large icon
setSmallIcon	Small icons
setContentIntent	Intention when clicking
setDeleteIntent	Intention when deleting
setFullScreenIntent	Full screen notification click intention , Incoming call 、 Ring the bell
setAutoCancel	Click auto cancel
setCategory	Notification category , apply “ Don't disturb mode ”
setVisibility	Screen visibility , apply “ Lock screen status ”
setNumber	Number of notification items
setWhen	Notice time
setShowWhen	Whether to display the notification time
setSound	Prompt tone
setVibrate	shock
setLights	Breathing lights
setPriority	priority ,7.0
setTimeoutAfter	Time to cancel ,8.0 And later
setProgress	speed of progress
setStyle	Notification style ,BigPictureStyle、BigTextStyle、MessagingStyle、InboxStyle、DecoratedCustomViewStyle
addAction	Actions on notifications ,10.0
setGroup	grouping
setColor	The background color

6、 Each version fits

since Android 4.0 Support notification , Almost every version has various changes , It is also hard to develop ...

6.1、Android 5.0

6.1.1、 Important notice

Android 5.0 Start , Support important notifications , Also known as header notice .

6.1.2、 Lock screen notice

Android 5.0 Start , Support lock screen notification , It is displayed on the lock screen desktop when the screen is locked .

from 8.0 Start , Users can enable or disable lock screen notification through notification channel settings ...

6.1.3、 Don't disturb mode

5.0 Start , All sounds and vibrations will be organized in do not disturb mode ,8.0 In the future, it can be set according to the channel .

6.2、Android 7.0

6.2.1、 Set notification priority

7.1 And the following ：

        mBuilder = NotificationCompat.Builder([email protected], mNormalChannelId)
            ...
            .setPriority(NotificationCompat.PRIORITY_DEFAULT) // 7.0  set priority 

8.0 And above are changed into channels .

6.2.2、 Reply operation

7.0 Introduce the function of direct reply operation

private val KEY_TEXT_REPLY = "key_text_reply"
var replyLabel: String = resources.getString(R.string.reply_label)
var remoteInput: RemoteInput = RemoteInput.Builder(KEY_TEXT_REPLY).run {
    setLabel(replyLabel)
    build()
}

6.2.3、 Notice of news

7.0 Start to support message type notifications MessagingStyle

var notification = NotificationCompat.Builder(this, CHANNEL_ID)
        .setStyle(NotificationCompat.MessagingStyle("Me")
                .setConversationTitle("Team lunch")
                .addMessage("Hi", timestamp1, null) // Pass in null for user.
                .addMessage("What's up?", timestamp2, "Coworker")
                .addMessage("Not much", timestamp3, null)
                .addMessage("How about lunch?", timestamp4, "Coworker"))
        .build()

from 8.0 Start , The message type is displayed as a folding type ...

6.2.4、 Notification grouping

7.0 Start , Notification supports grouping , Where more than one notice applies .

6.3、Android 8.0

6.3.1、 Create notification channels

Create notification channels , And importance

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            val channel = NotificationChannel(mHighChannelId, mHighChannelName, NotificationManager.IMPORTANCE_HIGH)
            mManager.createNotificationChannel(channel)
        }

Delete channel

notificationManager.deleteNotificationChannel(id)

6.3.2、 Notice corner

8.0 Start , Support to set whether the corner mark on the desktop is displayed during notification

val mChannel = NotificationChannel(id, name, importance).apply {
    description = descriptionText
    setShowBadge(false)
}

6.3.3、 Notification restrictions

8.1 Start , Notification sounds cannot be emitted more than once per second .

6.3.4、 The background color

8.0 Start , Set the background color of the notification .

6.4、Android 10.0

6.4.1、 Add operation

        mBuilder = NotificationCompat.Builder([email protected], mHighChannelId)
            ...
            .addAction(R.mipmap.ic_avatar, " Go to see ", pendingIntent)//  Actions on notifications 

6.4.2、 Full screen intention

10.0 Full screen intent needs to be in manifest Apply for USE_FULL_SCREEN_INTENT jurisdiction

6.5、Android 12.0

6.5.1、 Unlock device

12.0 And above , You can set that you need to unlock the device to operate ：setAuthenticationRequired

val moreSecureNotification = Notification.Builder(context, NotificationListenerVerifierActivity.TAG)
    .addAction(...)
    // from a lock screen.
    .setAuthenticationRequired(true)
    .build()

6.5.2、 Custom notifications

from 12.0 Start , Fully customized notifications will not be supported , Would provide Notification.DecoratedCustomViewStyle replace ...

6.5.3、PendingIntent

12.0 It needs to be clearly set up flag, Otherwise, there will be an error ：

java.lang.IllegalArgumentException: com.example.imdemo: Targeting S+ (version 31 and above) requires that one of FLAG_IMMUTABLE or FLAG_MUTABLE be specified when creating a PendingIntent. Strongly consider using FLAG_IMMUTABLE, only use FLAG_MUTABLE if some functionality depends on the PendingIntent being mutable, e.g. if it needs to be used with inline replies or bubbles.

        mFlag = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
            PendingIntent.FLAG_IMMUTABLE
        } else {
            PendingIntent.FLAG_UPDATE_CURRENT
        }
        val intentStop = Intent(mStopAction)
        val pendingIntentStop = PendingIntent.getBroadcast([email protected], 0, intentStop, mFlag)
        views.setOnClickPendingIntent(R.id.btn_stop, pendingIntentStop)

After carding and adapting , I really feel that Androider bitter

7、Github

github.com/yechaoa/Mat…

The code also has detailed comments , welcome star

8、 Reference documents

• Notifications Overview
• NotificationManager
• Notification.Builder
• Notification
• NotificationChannel
• Create a Custom Notification Layout

author ：yechaoa
link ：https://juejin.cn/post/7113509911887085581
source ： Rare earth digs gold
The copyright belongs to the author . Commercial reprint please contact the author for authorization , Non-commercial reprint please indicate the source .