Email 当有人在地理围栏外时如何发送邮件

所以我尝试为airsoft创建一个geofence应用程序。所以地理围栏的位置是有效的，但我想补充的另一件事是，如果用户在地理围栏外，它每分钟都会发送一封带有他的名字的邮件。 现在，它只是向用户发送通知，但我不知道如何让应用程序发送带有用户名的邮件。我试图创建一个列表，列出屏幕上显示的区域之外的用户，但没有成功。如果你有一些建议或想法，让我的应用程序工作，不要犹豫与我联系。这是我想要添加邮件部分的通知代码。谢谢大家!

    switch (transitionType) {
        case Geofence.GEOFENCE_TRANSITION_ENTER:
            Toast.makeText(context, "GEOFENCE_TRANSITION_ENTER", Toast.LENGTH_SHORT).show();
            notificationHelper.sendHighPriorityNotification("GEOFENCE_TRANSITION_ENTER", "", MapsActivity.class);
            break;
        case Geofence.GEOFENCE_TRANSITION_DWELL:
            Toast.makeText(context, "GEOFENCE_TRANSITION_DWELL", Toast.LENGTH_SHORT).show();
            break;
        case Geofence.GEOFENCE_TRANSITION_EXIT:
            Toast.makeText(context, "GEOFENCE_TRANSITION_EXIT", Toast.LENGTH_SHORT).show();
            notificationHelper.sendHighPriorityNotification("GEOFENCE_TRANSITION_EXIT", "", MapsActivity.class);
            notificationHelper.sendHighPriorityNotification("GEOFENCE_TRANSITION_EXIT", "", MapsActivity.class);
            notificationHelper.sendHighPriorityNotification("GEOFENCE_TRANSITION_EXIT", "", MapsActivity.class);
            notificationHelper.sendHighPriorityNotification("GEOFENCE_TRANSITION_EXIT", "", MapsActivity.class);
            notificationHelper.sendHighPriorityNotification("GEOFENCE_TRANSITION_EXIT", "", MapsActivity.class);
            notificationHelper.sendHighPriorityNotification("GEOFENCE_TRANSITION_EXIT", "", MapsActivity.class);


            break;
    }