This post dates from 2014, when I was using a Nokia X and an old Android SDK. The udev and user-group instructions were updated for Ubuntu 24.04 LTS on 2026-10-13. The old SYSFS rule and Upstart restart procedure no longer apply; the adb_usb.ini workaround remains at the end as a historical note.

1. Problem Overview

Recently, while developing for a Nokia project, I encountered the following issue:

When I plugged in a Nokia X, the computer did not respond at all—it wasn’t recognized. My colleague’s Windows machine also failed to detect it. After searching Google for a long time, I finally found a solution. Since I didn’t record it originally and later forgot how to configure it when helping someone else, I decided to document it here for everyone.

2. Solution

Enable USB debugging on the device and use a cable that supports data transfer. Check the selected Platform-Tools version with adb version, then inspect the connection using adb devices -l.

• Empty list: check the cable, port, USB debugging setting, and whether the host enumerates the device.
• no permissions: check Linux udev rules and the current user’s groups.
• unauthorized: ADB has found the device; unlock it and accept the RSA debugging prompt.
• offline: the device is not responding normally to ADB; reconnect it or restart the ADB server and inspect the state again.

USB enumeration, host permissions, and device authorization are separate checks. See the ADB reference and hardware-device setup guide.

1. Introduction to Accessibility Service

Updated 2026-10-13: This article was originally written in 2014 and covers accessibility service configuration available from Android 4.0 (API 14). Accessibility services remain supported, but using them as a general notification-center API is outdated. Android 4.3 (API 18) introduced NotificationListenerService for that purpose. The examples below correct service declarations and explain the node-recycling change in Android 13 (API 33).

Accessibility services help people with disabilities, or people temporarily unable to interact with a device, use applications. They can read interface text aloud or provide haptic feedback. This section covers service creation, event handling, and inspecting accessibility nodes.

The system binds an AccessibilityService after the user enables it; it is not started like an ordinary background task service. The examples give you a service skeleton and a few methods. To use them in your app, you’ll still need to add text-to-speech, a settings interface, and application resources. See the service lifecycle and configuration reference.