@OwnerUser public static boolean launchApp(final Context context, final String pkg, final UserHandle profile) {
		final LauncherApps launcher_apps = requireNonNull((LauncherApps) context.getSystemService(Context.LAUNCHER_APPS_SERVICE));
		try {
			final List<LauncherActivityInfo> activities = launcher_apps.getActivityList(pkg, profile);
			if (activities == null || activities.isEmpty()) return false;
			launcher_apps.startMainActivity(activities.get(0).getComponentName(), profile, null, null);
		} catch (final SecurityException e) {		// SecurityException: Cannot retrieve activities for unrelated profile 10
			Log.e(TAG, "Error launching app: " + pkg + " @ user " + profile, e);
			return false;
		}
		return true;
	}
@return error information, or empty string for success.
shared/src/main/java/com/oasisfeng/island/engine/IslandManager.java