Begin by taking a look at the dialog box you need to create.

The dialog box contains the following elements:

• Two sets of radio buttons.

  One set of buttons determines the polyline style of the boundary, and the other set
  of buttons specifies the tile entity creation method (ActiveX, entmake, or command). Only one radio button in a set can be selected at one time.

• Edit boxes for specifying the radius of tiles and the spacing between tiles.
• A standard set of OK and Cancel buttons.

Dialog box components are referred to as tiles in DCL. Writing the complete contents of a dialog box DCL file may seem overwhelming.
The trick is to sketch out what you want, break it down into sections, then write
each section.

To define the dialog box

1. Open a new file in the Visual LISP text editor window.
2. Enter the following statement in the new file:

   label = "Garden Path Tile Specifications

   This DCL statement defines the title of the dialog box window.

3. Define the radio buttons for specifying polyline type by adding the following code:

   : boxed_radio_column {    // defines the radio button areas
     label = "Outline Polyline Type
     : radio_button {        // defines the lightweight radio button
       label = "&Lightweight
       key = "gp_lw
       value = "1
      }
   : radio_button {       // defines the old-style polyline radio button
     label = "&Old-style
     key = "gp_hw
    }
   }

   The boxed_radio_column DCL directive defines a box boundary and allows you to specify a label for the set
   of buttons. Within the boundary, you specify the radio buttons you need by adding
   radio_button directives. Each radio button requires a label and a key. The key is the name by which your AutoLISP code can refer to the button.

   Notice that the radio button labeled “lightweightâ€‌ is given a value of 1. A value
   of 1 (a string, not an integer) assigned to a button makes it the default choice in
   a row of buttons. In other words, when you first display the dialog, this button will
   be selected. Also notice that in DCL files, double-slash characters, not semicolons
   as in AutoLISP, indicate a comment.

4. Define the radio column for the selection of the entity creation style by adding
   the following code:

   : boxed_radio_column {     // defines the radio button areas
     label = "Tile Creation Method
     : radio_button {         // defines the ActiveX radio button
       label = "&ActiveX Automation
       key = "gp_actx
       value = "1
      }
   : radio_button {          // defines the (entmake) radio button
     label = "&Entmake
     key = "gp_emake
    }
   : radio_button {          // defines the (command) radio button
     label = "&Command
     key = "gp_cmd
    }
   }

5. Add the following code to define the edit box tiles that allow users to enter the
   numbers specifying tile size and spacing:

   : edit_box {      // defines the Radius of Tile edit box
     label = "&Radius of tile
     key = "gp_trad
     edit_width = 6;
   }
   : edit_box {      // defines the Spacing Between Tiles edit box
     label = "S&pacing between tiles
     key = "gp_spac
     edit_width = 6;
   }

   Notice that this definition does not set any initial values for the edit boxes. You
   will set default values for each edit box in your AutoLISP program.

6. Add the following code for the OK and Cancel buttons:

   : row {          // defines the OK/Cancel button row
     : spacer { width = 1; }
     : button {    // defines the OK button
       label = "OK
       is_default = true;
       key = "accept
       width = 8;
       fixed_width = true;
     }
     : button {    // defines the Cancel button
       label = "Cancel
       is_cancel = true;
       key = "cancel
       width = 8;
       fixed_width = true;
     }
     : spacer { width = 1;}
   }

   Both buttons are defined within a row, so they line up horizontally.

7. Scroll to the beginning of the text editor window and insert the following statement
   as the first line in your DCL:

   gp_mainDialog : dialog {

8. The dialog directive requires a closing brace, so scroll to the end of the file and add the
   brace as the last line of DCL code:

   }