How to know if Android TalkBack is active?

You can create an inline function in kotlin like:

fun Context.isScreenReaderOn():Boolean{
    val am = getSystemService(Context.ACCESSIBILITY_SERVICE) as AccessibilityManager
    if (am != null && am.isEnabled) {
        val serviceInfoList =
            am.getEnabledAccessibilityServiceList(AccessibilityServiceInfo.FEEDBACK_SPOKEN)
        if (!serviceInfoList.isEmpty())
            return true
    }
    return false}

And then you can just call it whenever you need it like:

if(context.isScreenReaderOn()){
...
}

Tested and works fine for now.

The recommended way of doing this is to query the AccessibilityManager for the enabled state of accessibility services.

AccessibilityManager am = (AccessibilityManager) getSystemService(ACCESSIBILITY_SERVICE);
boolean isAccessibilityEnabled = am.isEnabled();
boolean isExploreByTouchEnabled = am.isTouchExplorationEnabled();

Novoda have released a library called accessibilitools which does this check. It queries the accessibility manager to check if there are any accessibility services enabled that support the "spoken feedback" flag.

AccessibilityServices services = AccessibilityServices.newInstance(context);
services.isSpokenFeedbackEnabled();

---

public boolean isSpokenFeedbackEnabled() {
    List<AccessibilityServiceInfo> enabledServices = getEnabledServicesFor(AccessibilityServiceInfo.FEEDBACK_SPOKEN);
    return !enabledServices.isEmpty();
}

private List<AccessibilityServiceInfo> getEnabledServicesFor(int feedbackTypeFlags) {
    return accessibilityManager.getEnabledAccessibilityServiceList(feedbackTypeFlags);
}