安卓的通知适配(更新至9.0)

以下代码以compileVersion=28作为示例来演示

• 添加NotificationChannel（必需）

  • 当compileVersion>=26且Notification没有设置channelId时,8.0的系统上通知不会弹出，在logcat的error级别显示NotificationService提示日志：No Channel found for pkg=aaa, channelId=null,...notification=Notification(channel=null ...)

  • 可以使用两种方式给Notification对象添加channelId: NotificationCompat.Builder(context, channelId)...build()或者build.setChannelId(channelId)...

  • NotificationChannel创建: NotificationChannel(String channelId, CharSequence name, @Importance int importance)

    • channelIdbuild时设置给Notification的id
    • name显示在通知管理里的标题
    • importance此通道的重要性，5个等级范围

  • 在通知被notify(notification)之前必须确保通知的NotificationChannel已经被注册，api: createNotificationChannel(channel)

• 机型适配

  • 有的手机在添加channel后仍然无法弹出通知。追踪logcat发现有这么一句：

    E/NotificationService: Suppressing notification from package by user request.
    

    用户请求抑制此通知？追踪notify源码找到NotificationManagerService的enqueueNotificationInternal(......)方法：

    void enqueueNotificationInternal(final String pkg, final String opPkg, final int callingUid,final int callingPid, final String tag, final int id, final Notification notification,int incomingUserId) {
     ...
     if (!checkDisqualifyingFeatures(userId, notificationUid, id, tag, r)) {return;}
     ...
     mHandler.post(new EnqueueNotificationRunnable(userId, r));
    }
    private boolean checkDisqualifyingFeatures(int userId, int callingUid, int id, String tag,NotificationRecord r) {
      ...// blocked apps
      if (isBlocked(r, mUsageStats)) {return false;}
      return true;
    }
    protected boolean isBlocked(NotificationRecord r, NotificationUsageStats usageStats) {
      final String pkg = r.sbn.getPackageName();
      final int callingUid = r.sbn.getUid();
      final boolean isPackageSuspended = isPackageSuspendedForUser(pkg, callingUid);
      if (isPackageSuspended) {
          Slog.e(TAG, "Suppressing notification from package due to package suspended by administrator.");
          usageStats.registerSuspendedByAdmin(r);
          return isPackageSuspended;
      }
      
      final boolean isBlocked = mRankingHelper.getImportance(pkg, callingUid) == NotificationManager.IMPORTANCE_NONE
                  || r.getChannel().getImportance() == NotificationManager.IMPORTANCE_NONE;
      if (isBlocked) {
          Slog.e(TAG, "Suppressing notification from package by user request.");
          usageStats.registerBlocked(r);
      }
      return isBlocked;
    }
    

    最终的isBlocked判断条件满足，导致notify操作被中断return。

  • 目前为止国产rom现状是：

    • 通知总权限在华为EMUI/魅族flyme/原生系统上默认是打开的，MIUI/VIVO/OPPO是默认关闭的

    • 渠道开关在OPPO手机上是默认关闭的，在开启总权限后还需要开启相关的类别(对应channel的name)才能正常使用。而测试的其他手机在开启总开关后自动开启channelId的通知开关。
      

  • 这么检测通知权限：

    public static boolean isNotificationEnabled(Context context,String channelId) {
        NotificationManagerCompat managerCompat = NotificationManagerCompat.from(context);
        NotificationManager manager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
        boolean returnValue = managerCompat.areNotificationsEnabled();
        if(manager == null || Build.VERSION.SDK_INT < Build.VERSION_CODES.O){
            return returnValue;
        }
        NotificationChannel channel = manager.getNotificationChannel(channelId);
        if(channel == null){
            channel = new NotificationChannel(channelId,"我的推送类别",NotificationManager.IMPORTANCE_HIGH);
            manager.createNotificationChannel(channel);
    
            下面的获取操作必需，创建的channel和获取到的channel的IMPORTANCE可能不一样，OPPO默认IMPORTANCE_NONE。
            channel = manager.getNotificationChannel(channelId);
        }
        return returnValue && channel.getImportance() != NotificationManager.IMPORTANCE_NONE;
    }
    

  • 跳转通知管理页面的代码：

    boolean isNotifyEnable = NotificationManagerCompat.from(context).areNotificationsEnabled();
    boolean isChannelEnable = true;
    if (Build.VERSION.SDK_INT >= 26) {
        isChannelEnable = channel.getImportance() != NotificationManager.IMPORTANCE_NONE;
    }
    if (isNotifyEnable && isChannelEnable) {
        manager.notify(notifyId, notification);  正常notify
    } else if (!isNotifyEnable) {
        Intent intent = new Intent();
        if(!(context instanceOf Activity)){
            intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        }
        if (Build.VERSION.SDK_INT >= 26) {
            intent.setAction(Settings.ACTION_APP_NOTIFICATION_SETTINGS);
            context.startActivity(intent.putExtra(Settings.EXTRA_APP_PACKAGE, getPackageName()));
        }else if (Build.VERSION.SDK_INT >= 21) {
            intent.setAction("android.settings.APP_NOTIFICATION_SETTINGS");
            context.startActivity(intent.putExtra("android.provider.extra.APP_PACKAGE", getPackageName()));
        } else if (Build.VERSION.SDK_INT >= 9) {
            intent.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
            intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            intent.setData(Uri.fromParts("package", getPackageName(), null));
            context.startActivity(intent);
        } else {低于9没有适配必要}
    }else{
       只打开了通知开关，但是关闭了当前channel的通知，开发者需要根据通知重要性,自行决定如何提示用户
    }
    

    • 查看api21与api26的源码发现Settings. ACTION_APP_NOTIFICATION_SETTINGS 的值其实就是 "android.settings. APP_NOTIFICATION_SETTINGS",只是在26前这个常量是隐藏的。因此上述代码可简化掉api26那部分。
    • 创建的NotificationChannel和notify时获取的NotificationChannel可能是不同的。因为在service层保存的实现方法国产rom做了更改。以防万一，请使用manager.getNotificationChannel(channelId)生成的NotificationChannel对象
    • 测试时发现vivo X21有两个通知管理页面：
      

      右边明显很漂酿啊有木有
      右侧的设计很好看，使用shell 命令dumpsys activity | grep -i run找到落地页(包名：com.android.systemui Activity名：com.vivo.systemui.statusbar.notification.settings.channels.NotificationSettingsActivity) 跑了下崩了，提示Permission Denial: starting Intent{...}not exported from uid 10023。activity没有设置为exported，有空了看看源码是否有破解方法...

• CompileSdkVersion<26时的机型适配

  • NotificationChannel这个API是在安卓8.0引入，所以当编译版本低于26时，不能加入channel，但是经过测试在vivo的安卓8.0手机上提示Suppressing notification from package by user request 通知无法弹出
  • areNotificationsEnabled 在安卓7.0(api24)加入，对应的support支持包最低v7:24.0.0。如果编译版本不低于api24，做如下适配：

    boolean isNotifyEnable = NotificationManagerCompat.from(this).areNotificationsEnabled();
    if(isNotifyEnable){
        manager.notify(notifyId,notification);
    }else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
        startActivity(new Intent("android.settings.APP_NOTIFICATION_SETTINGS")
              .putExtra("android.provider.extra.APP_PACKAGE", getPackageName()));
    } else/* if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.GINGERBREAD) */{
        Intent intent = new Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        intent.setData(Uri.fromParts("package", getPackageName(), null));
        startActivity(intent);
    }   考虑到目前app没人再适配android 2.x,因此最后一个else省略
    

  • 如果编译版本低于24，可参考高版本api自行实现，这里就不贴出了。目前各应用商店都在强制提升targetVersion，以后如果是上应用市场的app不会再有低于26的编译版本了