MODULE ObxControls;
(**
project = "BlackBox"
organization = "www.oberon.ch"
contributors = "Oberon microsystems"
version = "System/Rsrc/About"
copyright = "System/Rsrc/About"
license = "Docu/BB-License"
changes = ""
issues = ""
**)
IMPORT Dialog, Ports, Properties, Views;
CONST beginner = 0; advanced = 1; expert = 2; guru = 3; (* user classes *)
TYPE
View = POINTER TO RECORD (Views.View)
size: INTEGER (* border size in mm *)
END;
VAR
data*: RECORD
class*: INTEGER; (* current user class *)
list*: Dialog.List; (* list of currently available sizes, derived from class *)
width*: INTEGER (* width of next view to be opened. Derived from
class, or entered through a text entry field *)
END;
predef: ARRAY 6 OF INTEGER; (* table of predefined sizes *)
PROCEDURE SetList;
BEGIN
IF data.class = beginner THEN
data.list.SetLen(1);
data.list.SetItem(0, "default")
ELSIF data.class = advanced THEN
data.list.SetLen(4);
data.list.SetItem(0, "default");
data.list.SetItem(1, "small");
data.list.SetItem(2, "medium");
data.list.SetItem(3, "large");
ELSE
data.list.SetLen(6);
data.list.SetItem(0, "default");
data.list.SetItem(1, "small");
data.list.SetItem(2, "medium");
data.list.SetItem(3, "large");
data.list.SetItem(4, "tiny");
data.list.SetItem(5, "huge");
END
END SetList;
(* View *)
PROCEDURE (v: View) CopyFromSimpleView (source: Views.View);
BEGIN
v.size := source(View).size
END CopyFromSimpleView;
PROCEDURE (v: View) Restore (f: Views.Frame; l, t, r, b: INTEGER);
BEGIN (* fill view with a red square of size v.size *)
IF v.size = 0 THEN v.size := predef[0] END; (* lazy initialization of size *)
f.DrawRect(0, 0, v.size, v.size, Ports.fill, Ports.red)
END Restore;
PROCEDURE (v: View) HandlePropMsg (VAR msg: Views.PropMessage);
BEGIN
WITH msg: Properties.SizePref DO
IF v.size = 0 THEN v.size := predef[0] END; (* lazy initialization of size *)
msg.w := v.size; msg.h := v.size (* tell environment about desired width and height *)
ELSE (* ignore other messages *)
END
END HandlePropMsg;
(* notifiers *)
PROCEDURE ClassNotify* (op, from, to: INTEGER);
BEGIN (* react to change in data.class *)
IF op = Dialog.changed THEN
IF (to = beginner) OR (to = advanced) & (data.list.index > 3) THEN
(* if class is reduced, make sure that selection contains legal elements *)
data.list.index := 0; data.width := predef[0]; (* modify interactor *)
Dialog.Update(data) (* redraw controls where necessary *)
END;
SetList;
Dialog.UpdateList(data.list) (* reconstruct list box contents *)
END
END ClassNotify;
PROCEDURE ListNotify* (op, from, to: INTEGER);
BEGIN (* reacto to change in data.list (index to was selected) *)
IF op = Dialog.changed THEN
data.width := predef[to]; (* modify interactor *)
Dialog.Update(data) (* redraw controls where necessary *)
END
END ListNotify;
(* guards *)
PROCEDURE ListGuard* (VAR par: Dialog.Par);
BEGIN (* disable list box for a beginner *)
par.disabled := data.class = beginner
END ListGuard;
PROCEDURE WidthGuard* (VAR par: Dialog.Par);
BEGIN (* make text entry field read-only if user is not guru *)
par.readOnly := data.class # guru
END WidthGuard;
(* commands *)
PROCEDURE Open*;
VAR v: View;
BEGIN
NEW(v); (* create and initialize a new view *)
v.size := data.width * Ports.mm; (* define view's size in function of class *)
Views.OpenAux(v, "Example") (* open the view in a window *)
END Open;
BEGIN (* initialization of global variables *)
predef[0] := 40; predef[1] := 30; predef[2] := 50; (* predefined sizes *)
predef[3] := 70; predef[4] := 20; predef[5] := 100;
data.class := beginner; (* default values *)
data.list.index := 0;
data.width := predef[0];
SetList
END ObxControls.