一、判断应用是否包含监听权限

private fun isEnabled(): Boolean {
    val pkgName = packageName
    val flat: String =
        Settings.Secure.getString(contentResolver, "enabled_notification_listeners")
    if (!TextUtils.isEmpty(flat)) {
        val names = flat.split(":".toRegex()).toTypedArray()
        for (i in names.indices) {
            val cn = ComponentName.unflattenFromString(names[i])
            if (cn != null) {
                if (TextUtils.equals(pkgName, cn.packageName)) {
                    return true
                }
            }
        }
    }
    return false
}

二、开启监听和跳转

if (!isEnabled()) {
    startActivity(Intent("android.settings.ACTION_NOTIFICATION_LISTENER_SETTINGS"))
} else {
    val toast =
        Toast.makeText(applicationContext, "监控器开关已打开", Toast.LENGTH_SHORT)
    toast.show()
}

if (isEnabled()) {
    startActivity(Intent("android.settings.ACTION_NOTIFICATION_LISTENER_SETTINGS"))
} else {
    val toast =
        Toast.makeText(applicationContext, "监控器开关已关闭", Toast.LENGTH_SHORT)
    toast.show()
}

三、定义监听服务

@SuppressLint("NewApi")
class NotificationMonitorService : NotificationListenerService() {
    // 在收到消息时触发
    override fun onNotificationPosted(sbn: StatusBarNotification) {
        // 获取标准消息内容
        val extras = sbn.notification.extras
        // 获取接收消息APP的包名
        val notificationPkg = sbn.packageName
        // 获取接收消息的抬头
        val notificationTitle =
            extras.getString(Notification.EXTRA_TITLE)

        val tickerText = sbn.notification.tickerText
        // 获取接收消息的内容
        val notificationText = extras.getString(Notification.EXTRA_TEXT)
        Log.i(
            "iichen",
            "Notification 标准 posted notificationTitle &notificationText & tickerText &notificationPkg"
        )

        // 获取非标准通知内容
        val view = getContentView(this,sbn.notification)
        view?.apply {
            val content = getContent(this)
            Log.i(
                "iichen",
                "Notification 非标准 posted notificationTitle &content"
            )
        }

    }

    // 在删除消息时触发
    override fun onNotificationRemoved(sbn: StatusBarNotification) {
        // TODO Auto-generated method stub
        val extras = sbn.notification.extras
        // 获取接收消息APP的包名
        val notificationPkg = sbn.packageName
        // 获取接收消息的抬头
        val notificationTitle =
            extras.getString(Notification.EXTRA_TITLE)
        // 获取接收消息的内容
        val notificationText = extras.getString(Notification.EXTRA_TEXT)
        Log.i(
            "iichen",
            "Notification removed notificationTitle &notificationText"
        )
    }

    //获取notification的view
    fun getContentView(context: Context?, notification: Notification): View? {
        var contentView: RemoteViews? = null
        //获取contentView
        if (notification.contentView != null) {
            contentView = notification.contentView
        } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
            contentView = Notification.Builder.recoverBuilder(context, notification)
                .createContentView()
        }

        //RemoteViews转成view
        var view: View? = null
        try {
            view = contentView?.apply(context, null)
        } catch (e: Throwable) {

        }
        return view
    }

    //获取view里面的文本
    fun getContent(view: View): String? {
        val stringBuilder = StringBuilder()
        traversalView(view, stringBuilder)
        return stringBuilder.toString()
    }

    //遍历View，获取TextView里面的文本内容
    private fun traversalView(
        view: View,
        stringBuilder: StringBuilder
    ) {
        if (view is ViewGroup) {
            val viewGroup = view as ViewGroup
            val count = viewGroup.childCount
            for (i in 0 until count) {
                val childView: View = viewGroup.getChildAt(i)
                traversalView(childView, stringBuilder)
            }
        } else {
            if (view is TextView) {
                val tv = view as TextView
                val text = tv.text
                stringBuilder.append(text)
                stringBuilder.append(";")
            }
        }
    }

}

四、清单文件配置