<?xml version="1.0"?>

<!DOCTYPE GUI [

  <!ELEMENT GUI
    (FRAME)+
  >

  <!ELEMENT FRAME
    ( PANEL | BUTTON )*
  >
  <!ATTLIST FRAME
    LAYOUT ( Border | Flow ) "Border"
    TITLE CDATA "Frame"
  >

  <!ELEMENT PANEL
    ( PANEL | BUTTON )*
  >
  <!ATTLIST PANEL
    PLACEMENT ( North | South | East | West | Center | Default ) "Default"
    LAYOUT ( Border | Flow ) "Flow"
  >

  <!ELEMENT BUTTON
    EMPTY
  >
  <!ATTLIST BUTTON
    PLACEMENT ( North | South | East | West | Center | Default ) "Default"
    LABEL CDATA "Button"
  >
]>

<GUI>
 <FRAME TITLE="One">
  <PANEL PLACEMENT="North">
   <BUTTON LABEL="North1"/>
   <BUTTON LABEL="North2"/>
  </PANEL>
  <PANEL PLACEMENT="South">
   <BUTTON LABEL="South"/>
  </PANEL>
  <PANEL PLACEMENT="Center">
   <BUTTON LABEL="Center"/>
  </PANEL>
 </FRAME>
 <FRAME TITLE="Two">
  <PANEL PLACEMENT="North">
   <BUTTON LABEL="North"/>
  </PANEL>
  <PANEL PLACEMENT="South">
   <BUTTON LABEL="South"/>
  </PANEL>
  <PANEL PLACEMENT="Center" LAYOUT="Border">
   <PANEL PLACEMENT="North" LAYOUT="Border">
    <BUTTON PLACEMENT="North" LABEL="Center:North:North"/>
   </PANEL>
   <PANEL PLACEMENT="South" LAYOUT="Border">
    <BUTTON PLACEMENT="South" LABEL="Center:South:South"/>
   </PANEL>
   <PANEL PLACEMENT="Center" LAYOUT="Border">
    <BUTTON PLACEMENT="North" LABEL="Center:Center:North"/>
    <BUTTON PLACEMENT="South" LABEL="Center:Center:South"/>
    <BUTTON PLACEMENT="Center" LABEL="Center:Center:Center"/>
   </PANEL>
  </PANEL>
 </FRAME>
 <FRAME TITLE="Three" LAYOUT="Flow">
  <BUTTON LABEL="A"/>
  <BUTTON LABEL="B"/>
 </FRAME>
</GUI>
