Details of notification (status bar notification)

Introduction to this section ：

This section brings Android Control used to display notification information in the status bar ：Notification, Believe most learn Android All know him very well , And there's a lot about Notification The tutorials are based on 2.x Of , and It is now common Android The equipment is basically 4.x above , Even 5.0 All of the above ; Their own Notification It's all different ！ This section is based on 4.x The above Notification, and 5.0 The above Notification We will do the advanced tutorial Android 5.0 The new features are explained in the chapter ~

The official document is right Notification Some introductions of ：

design idea ：Notifications in Android 4.4 and Lower

translation ： notice

API file ：Notification

Visit the above website , You may need a ladder ~

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1. Interpretation of design documents

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1）Notification Basic layout

The constituent elements above are ：

• Icon/Photo： Large icon
• Title/Name： title
• Message： Content information
• Timestamp： Notice time , The default is the time when the system sends a notification , It can also be done through setWhen() To set up
• Secondary Icon： Small icons
• Content text , A text on the left-hand side of the small icon

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2） Expand the layout

stay Jelly Bean You can provide more details of the event for the notification . You can expand the layout to show the first few lines of the message or the preview of the image . In this way, users can see more content - Sometimes you can even see the whole news . The user can go through pinch-zoom Or slide your fingers to open the extended layout .Android Two extended layouts are provided for a single message ( Words and images ) For you to use when developing applications .

 

 

About other design things , I won't mention them one by one , If you are interested, please check the above API file , I know This Notification stay 4.x The above versions can be varied ！ We pay more attention to How to write code to use this thing , Now let's learn Notification Usage of ！

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2.Notification The basic use process of

The status notification bar mainly involves 2 Classes ：Notification and NotificationManager

Notification： Notification information class , It corresponds to the properties of the notification bar

NotificationManager： It is the management class of status bar notification , Be responsible for sending notice 、 Clear notifications and other operations .

The basic process used ：

• Step 1.  get NotificationManager object ： NotificationManager mNManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
• Step 2.  Create a notification bar Builder Construction class ： Notification.Builder mBuilder = new Notification.Builder(this);
• Step 3.  Yes Builder Make relevant settings , Such as the title , Content , Icon , Action, etc ！
• Step 4. call Builder Of build() Method is notification assignment
• Step 5. call NotificationManager Of notify() Method send notification ！
• PS: In addition, we can call NotificationManager Of cancel() Method cancel notification

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3. Some methods related to setting up ：

Notification.Builder mBuilder = new Notification.Builder(this);

Then call the following related methods to set ：( official API file ：Notification.Builder) The common methods are as follows ：

• setContentTitle(CharSequence)： Set title
• setContentText(CharSequence)： Set contents
• setSubText(CharSequence)： Set a small line of text below the content
• setTicker(CharSequence)： Set the text message displayed at the top when you receive a notification
• setWhen(long)： Set notification time , The general setting is when receiving the notification System.currentTimeMillis()
• setSmallIcon(int)： Set the small icon in the lower right corner , This small icon will also be displayed at the top when receiving the notification
• setLargeIcon(Bitmap)： Set the large icon on the left
• setAutoCancel(boolean)： The user clicks Notification Whether to cancel the notification after clicking the panel ( The default is not to cancel )
• setDefaults(int)： Add a voice to the notification 、 The simplest of flashing lights and vibration effects 、 Use the default （defaults） attribute , You can combine multiple attributes ,
  Notification.DEFAULT_VIBRATE( Add default vibration reminder );
  Notification.DEFAULT_SOUND( Add default sound reminder );
  Notification.DEFAULT_LIGHTS( Add default Tri Color Light reminder )
  Notification.DEFAULT_ALL( Add default above 3 All kinds of reminders )
• setVibrate(long[])： Set the vibration mode , such as ：
  setVibrate(new long[] {0,300,500,700}); Delay 0ms, Then vibrate 300ms, In delay 500ms, Then vibrate 700ms, About Vibrate The usage will be explained later ！
• setLights(int argb, int onMs, int offMs)： Set tricolor lights , The parameters in turn are ： The color of the light , Light duration , Dark time , Not all colors are OK , It's about equipment , Some mobile phones don't have Tri Color Lights yet ; in addition , Also need to Notification Set up flags by Notification.FLAG_SHOW_LIGHTS To support three color light reminder ！

• setSound(Uri)： Set the ringing tone when receiving the notification , You can use the system , You can also set it yourself , Examples are as follows :
  .setDefaults(Notification.DEFAULT_SOUND) // Get the default ringtone
  .setSound(Uri.parse("file:///sdcard/xx/xx.mp3")) // Get custom ringtones
  .setSound(Uri.withAppendedPath(Audio.Media.INTERNAL_CONTENT_URI, "5")) // obtain Android Ringtones in Multimedia Library

• setOngoing(boolean)： Set to ture, Indicates that it is an ongoing notification . They are usually used to express A background task , Users actively participate in ( Such as playing music ) Or waiting in some way , Therefore, the equipment is occupied ( Like a file download , Synchronous operation , Active network connectivity )

• setProgress(int,int,boolean)： Set notification with progress bar The parameters are ： Maximum value of progress bar , Current progress , Whether the progress is uncertain If it is a determined progress bar ： call setProgress(max, progress, false) To set up notifications , When updating the progress, send a notification here progress, And remove the progress bar after the download , By calling setProgress(0, 0, false) As well as . If it is uncertain （ Continuous activity ） The progress bar , This shows that the activity is continuing when the processing progress cannot be accurately known , So call setProgress(0, 0, true) , At the end of the operation , call setProgress(0, 0, false) And update the notification to remove the indicator bar

• setContentIntent(PendingIntent)：PendingIntent and Intent It's a little different , It can set the number of executions , Mainly used for remote service communication 、 Alarm 、 notice 、 starter 、 In SMS , In general, it is less used . For example, here through Pending start-up Activity：getActivity(Context, int, Intent, int), Of course, you can also start Service perhaps Broadcast PendingIntent Bit identifier of ( Fourth parameter )：
  FLAG_ONE_SHOT  Means returned PendingIntent Can only be executed once , Automatically cancel after execution
  FLAG_NO_CREATE  It means if you describe PendingIntent non-existent , Do not create corresponding PendingIntent, It's going back to NULL
  FLAG_CANCEL_CURRENT  It means corresponding PendingIntent Already exist , Then cancel the former , And create a new one PendingIntent, This helps keep the data up to date , Communication scenarios that can be used for instant messaging
  FLAG_UPDATE_CURRENT  Means updated PendingIntent
  Examples of use ：

  // Click and jump Activity
  Intent intent = new Intent(context,XXX.class);  
  PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, 0);  
  mBuilder.setContentIntent(pendingIntent)  

• setPriority(int)： set priority ：

  priority	user
  MAX	Important and urgent notice , Inform the user that this event is time critical or needs to be handled immediately .
  HIGH	High priority is used for important communication content , For example, SMS or chat , These are more interesting to users .
  DEFAULT	The default priority is used for notifications without special priority classification .
  LOW	Low priority can notify users of events that are not very urgent .
  MIN	For background messages ( For example, weather or location information ). The lowest priority notification will only display icons in the status bar , Only when the user pulls down the notification drawer can you see the content .

  Corresponding attribute ：Notification.PRIORITY_HIGH...

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4. Code example ： The most common Notification：

Let's write a simple example to experience Notification Usage of ：

Run the renderings ：

 

Key code ：

Direct paste here MainActivity.java Code for ：

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    private Context mContext;
    private NotificationManager mNManager;
    private Notification notify1;
    Bitmap LargeBitmap = null;
    private static final int NOTIFYID_1 = 1;

    private Button btn_show_normal;
    private Button btn_close_normal;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mContext = MainActivity.this;
        // Create large icons Bitmap
        LargeBitmap = BitmapFactory.decodeResource(getResources(), R.mipmap.iv_lc_icon);
        mNManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
        bindView();

    }


    private void bindView() {
        btn_show_normal = (Button) findViewById(R.id.btn_show_normal);
        btn_close_normal = (Button) findViewById(R.id.btn_close_normal);
        btn_show_normal.setOnClickListener(this);
        btn_close_normal.setOnClickListener(this);
    }


    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.btn_show_normal:
                // Define a PendingIntent Click on Notification Start one after Activity
                Intent it = new Intent(mContext, OtherActivity.class);
                PendingIntent pit = PendingIntent.getActivity(mContext, 0, it, 0);

                // Set pictures , Notification heading , Send time , Prompt method and other attributes 
                Notification.Builder mBuilder = new Notification.Builder(this);
                mBuilder.setContentTitle(" Ye Liangchen ")                        // title 
                        .setContentText(" I have a hundred ways to make you stay ~")      // Content 
                        .setSubText("—— Remember my name is ye Liangchen ")                    // A short paragraph below the content 
                        .setTicker(" Received the message sent by Ye Liangchen ~")             // The text message displayed in the status bar after receiving the message 
                        .setWhen(System.currentTimeMillis())           // Set notification time 
                        .setSmallIcon(R.mipmap.ic_lol_icon)            // Set up small icons 
                        .setLargeIcon(LargeBitmap)                     // Set the big icon 
                        .setDefaults(Notification.DEFAULT_LIGHTS | Notification.DEFAULT_VIBRATE)    // Set the default tricolor lights and vibrators 
                        .setSound(Uri.parse("android.resource://" + getPackageName() + "/" + R.raw.biaobiao))  // Set custom prompt tone 
                        .setAutoCancel(true)                           // Click set to cancel Notification
                        .setContentIntent(pit);                        // Set up PendingIntent
                notify1 = mBuilder.build();
                mNManager.notify(NOTIFYID_1, notify1);
                break;

            case R.id.btn_close_normal:
                // In addition to being able to ID To cancel Notification Outside , You can also call cancelAll(); Close all notifications generated by the app 
                mNManager.cancel(NOTIFYID_1);                          // Cancel Notification
                break;

        }
    }
}

The notes are very detailed , I won't go into details ~

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5. Code sample download ：

NotificationDemo.zip

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Summary of this section ：

well , This section introduces Notification stay 4.x Basic usage of version , It's very simple, isn't it ~
Of course, you can also customize Notification If you are interested, you can consult relevant materials by yourself , Here is not slow Studied ~ by the way , Part of this section refers to the following blog, Post link , You can also have a look at ： Android Notice bar Notification Integration of Study in an all-round way （ One DEMO Let you fully understand it ）  It's very detailed ~ That's all for this section , thank you ~

 

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