Android: How can I get current opened application name on screen [duplicate]

Use an AccessibilityService

• You can detect the currently active window by using an AccessibilityService.
• In the onAccessibilityEvent callback, check for the TYPE_WINDOW_STATE_CHANGED event type to determine when the current window changes.
• Check if the window is an activity by calling PackageManager.getActivityInfo().

I tested and working in Android 2.2 (API 8) through Android 7.1 (API 25).

public class MyAccessibilityService extends AccessibilityService {
    @Override
    protected void onServiceConnected() {
        super.onServiceConnected();

        //Configure these here for compatibility with API 13 and below.
        AccessibilityServiceInfo config = new AccessibilityServiceInfo();
        config.eventTypes = AccessibilityEvent.TYPE_WINDOW_STATE_CHANGED;
        config.feedbackType = AccessibilityServiceInfo.FEEDBACK_GENERIC;

        if (Build.VERSION.SDK_INT >= 16)
            //Just in case this helps
            config.flags = AccessibilityServiceInfo.FLAG_INCLUDE_NOT_IMPORTANT_VIEWS;

        setServiceInfo(config);
    }
    @Override
    public void onAccessibilityEvent(AccessibilityEvent accessibilityEvent) {
        Log.d("ABC-",accessibilityEvent.getPackageName()+" -- "+accessibilityEvent.getClassName());
        if (accessibilityEvent.getEventType() == AccessibilityEvent.TYPE_WINDOW_STATE_CHANGED) {
            if (accessibilityEvent.getPackageName() != null && accessibilityEvent.getClassName() != null) {
                ComponentName componentName = new ComponentName(
                        accessibilityEvent.getPackageName().toString(),
                        accessibilityEvent.getClassName().toString()
                );

                ActivityInfo activityInfo = tryGetActivity(componentName);
                boolean isActivity = activityInfo != null;
                if (isActivity)
                    Log.i("CurrentActivity", componentName.flattenToShortString());
            }
        }
    }

    private ActivityInfo tryGetActivity(ComponentName componentName) {
        try {
            return getPackageManager().getActivityInfo(componentName, 0);
        } catch (PackageManager.NameNotFoundException e) {
            return null;
        }
    }
    @Override
    public void onInterrupt() {

    }
}