/**
* @return Selected account to show contacts. <code>null</code> if
* <ul>
* <li>there is no selected account,
* <li>selected account does not exists or disabled,
* <li>Group by account is enabled.
* </ul>
*/
public String getSelectedAccount() {
if (SettingsManager.contactsShowAccounts()) return null;
String selected = SettingsManager.contactsSelectedAccount();
if (enabledAccounts.contains(selected)) return selected;
return null;
}
