Android O(8.0)Notification Channel使用姿势

上面这张图，将具有形同形态，相同表现形式的通知渠道A ，通知渠道B归纳到了同一个渠道组中。

1. 通知渠道的引入可以很方便的管理，和归纳同一种类型的通知Notification.
2. 通知渠道组的引入同样可以方便的管理，归纳同一种类型的通知渠道Channel.

1.首先看一下Android8.0之前的普通Notification的样式以及使用姿势

1. 可以看到是多个通知 ，无论是不是同一个应用的通知，逐个排列下来，占满了屏幕，不太友好

2. 接下来我们来看一下代码

   NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(getApplicationContext(), CHANNEL_ID)
               .setSmallIcon(android.R.drawable.stat_notify_chat)
               .setContentTitle("你有一条新的消息")
               .setContentText("this is normal notification style")
               .setTicker("notification ticker")
               .setPriority(1000)
               .setAutoCancel(true)
               .setVibrate(new long[]{100, 200, 300, 400, 500, 400, 300, 200, 400})
               .setNumber(3)
               .setDefaults(Notification.DEFAULT_SOUND | Notification.DEFAULT_VIBRATE)
               .setContentIntent(pendingResult)
               .setOngoing(true);
   
       Notification notification = mBuilder.build();
       getNotificationManager().notify(notifyId, notification);

   ---

   2.再来看一下带下载进度的通知栏Notification

   

3. 起一个线程来模拟 下载进度，间隔1秒更新一下 通知进度。

   final NotificationManager mNotifyManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
       final NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this, CHANNEL_ID);
       mBuilder.setContentTitle("Picture Download")
               .setContentText("Download in progress")
               .setOngoing(true)
               .setVibrate(new long[]{0})
               .setSound(null)
               .setTicker("notification ticker")
               .setDefaults(NotificationCompat.FLAG_LOCAL_ONLY)
               .setSmallIcon(android.R.drawable.stat_notify_chat);
       new Thread(
               new Runnable() {
                   @Override
                   public void run() {
                       int incr;
                       for (incr = 0; incr <= 100; incr += 5) {
                           mBuilder.setProgress(100, incr, false);
                           mBuilder.setSound(null);
                           mNotifyManager.notify(0, mBuilder.build());
                           try {
                               Thread.sleep(1000);
                           } catch (InterruptedException e) {
                           }
                       }
                       mBuilder.setContentText("Download complete").setProgress(0, 0, false);
                       mBuilder.setAutoCancel(true);
                       mBuilder.setOngoing(false);
                       mNotifyManager.notify(0, mBuilder.build());
                   }
               }
       ).start();

   ---

   3.再来看一下自定义布局的Notification

   

4. 创建一个布局资源，通过RemoteViews来 渲染，同时也绑定了点击事件

   
   RemoteViews remoteViews = new RemoteViews(getPackageName(), R.layout.remote_custom_notification);
       remoteViews.setTextViewText(R.id.title, "Custom Notification---title");
       remoteViews.setTextViewText(R.id.content, "Custom Notification---content");
   
       Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
       intent.setType("image/*");
       intent.addCategory(Intent.CATEGORY_OPENABLE);
   
       PendingIntent pendingIntent = PendingIntent.getActivity(this, REQUEST_CODE_NOTIFY, intent, PendingIntent.FLAG_UPDATE_CURRENT);
       Notification notification = new NotificationCompat.Builder(this, CHANNEL_ID)
               .setSmallIcon(android.R.drawable.stat_notify_chat)
               .setContent(remoteViews)
               .setTicker("ticker")
               .setContentIntent(pendingIntent).build();
   
       getNotificationManager().notify(notifyId, notification);

以上【1】【2】【3】就是常用的通知栏Notification的样式和使用姿势
- - -
### 4.下面来看一下Android 8.0上通知渠道NotificationChannel 的应用
![NotificationChannel.png](http://upload-images.jianshu.io/upload_images/2432544-88f3f7a653560051.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)

1. 上图可以看到，相同通知渠道的通知已经被合并，而不是一一全部展开。
2.  如果你的项目TargetSDK在26以上，那么你在使用Notification的时候必须指定一个ChannelId，否则当然会报错
3. 下面是Android 8.0上通知渠道NotificationChannel 的使用代码段，注意点需要传入CHANNEL_ID（随意指定），CHANNEL_NAME（随意指定）

NotificationChannel channel = new NotificationChannel(CHANNEL_ID, CHANNEL_NAME, NotificationManager.IMPORTANCE_HIGH);
channel.setBypassDnd(true); //设置绕过免打扰模式
channel.canBypassDnd(); //检测是否绕过免打扰模式
channel.setLockscreenVisibility(Notification.VISIBILITY_SECRET);//设置在锁屏界面上显示这条通知
channel.setDescription("description of this notification");
channel.setLightColor(Color.GREEN);
channel.setName("name of this notification");
channel.setShowBadge(true);
channel.setVibrationPattern(new long[]{100, 200, 300, 400, 500, 400, 300, 200, 400});
channel.enableVibration(true);
getNotificationManager().createNotificationChannel(channel);

- - -
### 5.如果要使用通知渠道组NotificationChannelGroup，那么它的样式跟上图一样，使用姿势是下面这样
1.  这里在渠道组NotificationChannelGroup上绑定了两个通知渠道NotificationChannel ，每个渠道下各有一个通知Notification.

getNotificationManager().createNotificationChannelGroup(new NotificationChannelGroup(GROUP_ID, "GROUP_CHANNEL"));

    NotificationChannel channel = new NotificationChannel(CHANNEL_ID, CHANNEL_NAME, NotificationManager.IMPORTANCE_HIGH);
    channel.setGroup(GROUP_ID);
    channel.setShowBadge(true);
    channel.setLightColor(Color.RED);
    channel.enableLights(true);
    getNotificationManager().createNotificationChannel(channel);

    NotificationChannel channel2 = new NotificationChannel(CHANNEL_ID_2, CHANNEL_NAME, NotificationManager.IMPORTANCE_HIGH);
    channel2.setGroup(GROUP_ID);
    channel2.setShowBadge(true);
    channel2.setLightColor(Color.RED);
    channel2.enableLights(true);
    getNotificationManager().createNotificationChannel(channel2);

    Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
    intent.setType("image/*");
    intent.addCategory(Intent.CATEGORY_OPENABLE);
    PendingIntent pendingResult = PendingIntent.getActivity(this, REQUEST_CODE_NOTIFY, intent, PendingIntent.FLAG_UPDATE_CURRENT);

    NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(getApplicationContext(), CHANNEL_ID)
            .setSmallIcon(android.R.drawable.stat_notify_chat)
            .setContentTitle("notification title_9")
            .setContentText("notification content_9")
            .setPriority(1000)
            .setAutoCancel(true)
            .setVibrate(new long[]{100, 200, 300, 400, 500, 400, 300, 200, 400})
            .setNumber(3)
            .setDefaults(Notification.DEFAULT_LIGHTS)
            .setContentIntent(pendingResult)
            .setOngoing(true);

    NotificationCompat.Builder mBuilder1 = new NotificationCompat.Builder(getApplicationContext(), CHANNEL_ID_2)
            .setSmallIcon(android.R.drawable.stat_notify_chat)
            .setContentTitle("notification title_10")
            .setContentText("notification content_10")
            .setPriority(1000)
            .setAutoCancel(true)
            .setVibrate(new long[]{100, 200, 300, 400, 500, 400, 300, 200, 400})
            .setNumber(15)
            .setDefaults(Notification.DEFAULT_SOUND | Notification.DEFAULT_VIBRATE)
            .setContentIntent(pendingResult)
            .setOngoing(true);

    getNotificationManager().notify(9, mBuilder.build());
    getNotificationManager().notify(10, mBuilder1.build());

- - -
### 6.通知渠道的管理
1.删除渠道

getNotificationManager().deleteNotificationChannel(CHANNEL_ID);

2.删除渠道组

getNotificationManager().deleteNotificationChannelGroup(GROUP_ID);

以上便是老版本上使用Notification 和 Android 8.0上通知渠道，渠道组的姿势。
- - -