Example: Quick Overview of Dialog Boxes (DCL)

 
 
 

This example explains how to create a basic dialog box and display it using AutoLISP.

NoteDCL support in AutoLISP is limited to Windows only.

Creating the DCL File

This DCL defines a dialog box labeled Sample Dialog Box that contains a text tile and a single OK button. The DCL resides in a file named hello.dcl.

  1. Copy the following code to the clipboard.

    Highlight the DCL code and press Ctrl+C, or right-click and click Copy.

    hello : dialog
    {
      label = "Sample Dialog Box";
      : text {
        label = "Hello, world.";
      }
      ok_only;
    }
  2. In the Visual LISP Editor, click File New File.
  3. In the new editor window, press Ctrl+V, or right-click and click Paste.
  4. Click File Save As. In the Save-as dialog box, Save As Type drop-down list, select DCL Source Files. In the File Name field, enter hello.dcl. Browse to a location to store the DCL file and click Save.
    NoteMake sure the DCL file is saved to one of the folders in the AutoCAD Support File Search Path.

Displaying the dialog box and responding to the user pressing OK

  1. Copy the following code to the clipboard.

    Highlight the DCL code and press Ctrl+C, or right-click and click Copy.

    (defun C:HELLO ( / dcl_id )
      (setq dcl_id (load_dialog "hello.dcl")) ; Load the DCL file.
      (if (not (new_dialog "hello" dcl_id))   ; Initialize the dialog.
        (exit)                                ; Exit if this does not work.
      )
      (start_dialog)                          ; Display the dialog box.
      (unload_dialog dcl_id)                  ; Unload the DCL file.
     (princ)
    )

  2. In the Visual LISP Editor, click File New File.
  3. In the new editor window, press Ctrl+V, or right-click and click Paste.
  4. Click File Save As. In the Save-as dialog box, Save As Type drop-down list, select Lisp Source Files. In the File Name field, enter hello.lsp. Browse to a location to store the LSP file and click Save.
    NoteMake sure the LSP file is saved to one of the folders in the AutoCAD Support File Search Path.
  5. Click Tools Load Text in Editor.
  6. In AutoCAD, at the Command prompt, enter hello and press Enter.
  7. In Sample Dialog Box, click OK.

The following explains line by line what the AutoLISP program does:

Note that the start_dialog call remains active until the user selects a tile (usually a button) whose associated action expression calls done_dialog. The done_dialog call can be issued explicitly by the tile. The done_dialog call is also issued by the selected tile if its is_cancel attribute is set to true.

WarningIn theory, the dialog box facility takes control of input at the time you call start_dialog, but the operating system takes control when you call new_dialog. This has no effect on writing programs. However, if you invoke these functions interactively (at the AutoCAD Command prompt), you must enter them as one statement. Enclose them within a progn or another function. If you do not, the interactive call to new_dialog can freeze the screen. Calling new_dialog and start_dialog interactively can be useful during debugging.