title: Lightswitch custom addandeditnew screen
body: <p>I have a List and details app for the clients entity, when the user clicks the <code>addnewandedit</code> button I want to open a custom modal screen with a limited number of fields.</p>
  
  <p>In the guide it says that creating a new 'details' screen and setting this as default should do this, but it doesn't use the custom screen and still uses the auto generated one.</p>
  
  <p>I tried overriding the button with <code>application.showcustomAddClient()</code> but this opens it as a tab, not as a modal window like the auto generated one does.</p>
  
  <p>I then tried setting the <code>customaddclient</code> as a modal window but now when I click on <code>addandeditnew</code> I get a button which I have to click, which then opens the screen as a modal window, I can't work out why it won't open the modal window directly?</p>
  
  <p>I tried calling the <code>application.showscreen(customaddclient,Enumerable.Empty&lt;object&gt;())</code> but get an error in the syntax.</p>
  
  <p>Any help on how to specify which modal screen to use for a custom <code>addandeditnew</code> would be very helpful.</p>