<s>
Dialog	B-Language
Control	I-Language
Language	I-Language
(	O
DCL	O
)	O
is	O
a	O
high-level	O
description	O
language	O
and	O
interpreter	O
within	O
AutoCAD	B-Algorithm
for	O
creating	O
simple	O
graphical	O
dialogs	O
.	O
</s>
<s>
AutoLISP	B-Algorithm
extensions	O
use	O
it	O
to	O
interact	O
with	O
the	O
user	O
in	O
the	O
AutoCAD	B-Algorithm
environment	O
.	O
</s>
<s>
Unlike	O
other	O
major	O
GUI	B-Application
APIs	O
,	O
DCL	O
is	O
not	O
a	O
complete	O
GUI	B-Application
toolkit	O
for	O
application	O
programming	O
.	O
</s>
<s>
It	O
is	O
only	O
intended	O
for	O
providing	O
simple	O
dialogs	O
within	O
AutoCAD	B-Algorithm
.	O
</s>
<s>
DCL	O
is	O
object-oriented	B-Language
;	O
it	O
allows	O
re-use	O
through	O
inheritance	B-Language
and	O
composition	B-Language
.	O
</s>
<s>
A	O
'	O
tile	O
 '	O
represents	O
a	O
GUI	B-Application
widget	O
such	O
as	O
a	O
text	O
box	O
or	O
a	O
text	O
label	O
.	O
</s>
<s>
DCL	O
provides	O
built-in	O
tiles	O
for	O
all	O
major	O
widgets	O
,	O
and	O
new	O
tiles	O
can	O
be	O
defined	O
through	O
inheritance	B-Language
and	O
composition	B-Language
of	O
other	O
tiles	O
.	O
</s>
<s>
Certain	O
widgets	O
can	O
have	O
actions	O
associated	O
with	O
them	O
by	O
naming	O
an	O
AutoLISP	B-Algorithm
function	O
to	O
be	O
run	O
,	O
and	O
values	O
to	O
be	O
passed	O
to	O
it	O
.	O
</s>
<s>
Unlike	O
other	O
types	O
of	O
GUIs	B-Application
,	O
DCL	O
dialogs	O
cannot	O
be	O
changed	O
substantially	O
at	O
run	O
time	O
.	O
</s>
<s>
Here	O
is	O
an	O
example	O
DCL	O
file	O
(	O
and	O
accompanying	O
AutoLISP	B-Algorithm
file	O
)	O
demonstrating	O
the	O
major	O
features	O
of	O
DCL	O
.	O
</s>
<s>
A	O
DCL	O
dialog	O
is	O
instantiated	O
by	O
calling	O
a	O
series	O
of	O
functions	O
in	O
an	O
AutoLisp	B-Algorithm
file	O
.	O
</s>
<s>
Tiles	O
can	O
call	O
back	O
into	O
AutoLISP	B-Algorithm
code	O
on	O
certain	O
events	O
,	O
and	O
Lisp	O
can	O
manipulate	O
the	O
contents	O
of	O
tiles	O
while	O
the	O
dialog	O
is	O
running	O
.	O
</s>
<s>
For	O
creating	O
more	O
general	O
GUIs	B-Application
and	O
other	O
extensions	O
within	O
CAD	O
,	O
AutoDesk	O
provides	O
several	O
other	O
choices	O
.	O
</s>
<s>
The	O
ObjectARX	B-Application
API	O
for	O
C++	B-Language
allows	O
extensions	O
to	O
be	O
built	O
as	O
within	O
Microsoft	O
Visual	O
Studio	O
.	O
</s>
<s>
VBA	B-Language
allows	O
drag-and-drop	O
programming	O
for	O
AutoCAD	B-Algorithm
as	O
for	O
Microsoft	B-Application
Office	I-Application
and	O
other	O
applications	O
.	O
</s>
<s>
As	O
of	O
AutoCAD	B-Algorithm
2007	I-Algorithm
and	O
later	O
,	O
AutoLISP	B-Algorithm
or	O
Visual-LISP	O
programs	O
can	O
call	O
routines	O
written	O
in	O
Visual	O
Studio	O
.NET	O
(	O
VB	O
or	O
C#	O
)	O
.	O
</s>
