Android: How do you check if a particular AccessibilityService is enabled

I worked this one out myself in the end:

public boolean isAccessibilityEnabled() {
    int accessibilityEnabled = 0;
    final String LIGHTFLOW_ACCESSIBILITY_SERVICE = "com.example.test/com.example.text.ccessibilityService";
    boolean accessibilityFound = false;
    try {
        accessibilityEnabled = Settings.Secure.getInt(this.getContentResolver(),android.provider.Settings.Secure.ACCESSIBILITY_ENABLED);
        Log.d(LOGTAG, "ACCESSIBILITY: " + accessibilityEnabled);
    } catch (SettingNotFoundException e) {
        Log.d(LOGTAG, "Error finding setting, default accessibility to not found: " + e.getMessage());
    }

    TextUtils.SimpleStringSplitter mStringColonSplitter = new TextUtils.SimpleStringSplitter(':');

    if (accessibilityEnabled==1) {
        Log.d(LOGTAG, "***ACCESSIBILIY IS ENABLED***: ");

        String settingValue = Settings.Secure.getString(getContentResolver(), Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES);
        Log.d(LOGTAG, "Setting: " + settingValue);
        if (settingValue != null) {
             TextUtils.SimpleStringSplitter splitter = mStringColonSplitter;
             splitter.setString(settingValue);
             while (splitter.hasNext()) {
                 String accessabilityService = splitter.next();
                 Log.d(LOGTAG, "Setting: " + accessabilityService);
                 if (accessabilityService.equalsIgnoreCase(ACCESSIBILITY_SERVICE_NAME)){
                     Log.d(LOGTAG, "We've found the correct setting - accessibility is switched on!");
                     return true;
                 }
             }
        }

        Log.d(LOGTAG, "***END***");
    }
    else {
        Log.d(LOGTAG, "***ACCESSIBILIY IS DISABLED***");
    }
    return accessibilityFound;
}

Since API Level 14, it is also possible to obtain the enabled accessibility services through the AccessibilityManager:

public static boolean isAccessibilityServiceEnabled(Context context, Class<? extends AccessibilityService> service) {
    AccessibilityManager am = (AccessibilityManager) context.getSystemService(Context.ACCESSIBILITY_SERVICE);
    List<AccessibilityServiceInfo> enabledServices = am.getEnabledAccessibilityServiceList(AccessibilityServiceInfo.FEEDBACK_ALL_MASK);

    for (AccessibilityServiceInfo enabledService : enabledServices) {
        ServiceInfo enabledServiceInfo = enabledService.getResolveInfo().serviceInfo;
        if (enabledServiceInfo.packageName.equals(context.getPackageName()) && enabledServiceInfo.name.equals(service.getName()))
            return true;
    }

    return false;
}

Usage:

boolean enabled = isAccessibilityServiceEnabled(context, MyAccessibilityService.class);

Checking if the service is enabled

/**
 * Based on {@link com.android.settingslib.accessibility.AccessibilityUtils#getEnabledServicesFromSettings(Context,int)}
 * @see <a href="https://github.com/android/platform_frameworks_base/blob/d48e0d44f6676de6fd54fd8a017332edd6a9f096/packages/SettingsLib/src/com/android/settingslib/accessibility/AccessibilityUtils.java#L55">AccessibilityUtils</a>
 */
public static boolean isAccessibilityServiceEnabled(Context context, Class<?> accessibilityService) {
    ComponentName expectedComponentName = new ComponentName(context, accessibilityService);

    String enabledServicesSetting = Settings.Secure.getString(context.getContentResolver(),  Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES);
    if (enabledServicesSetting == null)
        return false;

    TextUtils.SimpleStringSplitter colonSplitter = new TextUtils.SimpleStringSplitter(':');
    colonSplitter.setString(enabledServicesSetting);

    while (colonSplitter.hasNext()) {
        String componentNameString = colonSplitter.next();
        ComponentName enabledService = ComponentName.unflattenFromString(componentNameString);

        if (enabledService != null && enabledService.equals(expectedComponentName))
            return true;
    }

    return false;
}

Usage:

boolean enabled = isAccessibilityServiceEnabled(context, MyAccessibilityService.class);

Detecting when the service is enabled or disabled

Make a callback:

ContentObserver observer = new ContentObserver() {
    @Override
    public void onChange(boolean selfChange) {
        super.onChange(selfChange);
        boolean accessibilityServiceEnabled = isAccessibilityServiceEnabled(context, MyAccessibilityService.class);
        //Do something here
    }
};

Subscribe:

Uri uri = Settings.Secure.getUriFor(Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES);
context.getContentResolver().registerContentObserver(uri, false, observer);

Unsubscribe when you're done:

context.getContentResolver().unregisterContentObserver(observer);

Note that this doesn't work with the getEnabledAccessibilityServiceList() approach since its values are out-of-sync with the Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES values. That's why I think using Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES is a better one-size-fits-all approach.