Menus.mesa; Written by S. McGregor
Last Edited by: McGregor, July 13, 1983 10:57 am
Last Edited by: Maxwell, December 17, 1982 9:58 am
DIRECTORY
Process USING [Milliseconds],
Rope USING [ROPE];
Menus: CEDAR DEFINITIONS = BEGIN
Menus are the "button-like" commands displayed across the top of a viewer.
Menu: TYPE = REF MenuRec;
A MenuEntry is an individual item in a menu
MenuEntry: TYPE = REF MenuEntryRec;
Creating menus
MenuLine: TYPE = [0..5);
CreateMenu:
PROC [lines: MenuLine ← 1]
RETURNS [menu: Menu] =
INLINE
{RETURN[NEW[MenuRec ← [linesUsed: lines]]]} ;
Create a new menu with some number of lines of entries
CopyMenu:
PROC [old: Menu]
RETURNS [new: Menu] ;
Copy a menu and all of its entries
Menu and Button notifications
MouseButton:
TYPE = { red, yellow, blue } ;
Mouse buttons from left to right
ClickProc,
MenuProc:
TYPE =
PROC [parent:
REF
ANY, clientData:
REF
ANY ←
NIL,
mouseButton: MouseButton ← red, shift, control: BOOL ← FALSE] ;
For menus, the parent field will contain the parent Viewer; for buttons, parent will be the button Viewer itself. Use NARROW to convert a REF ANY to a Viewer. mouseButton indicates how the user invoked the button or menu. shift and control indicate the state of the shift and control keys when the menu or button was invoked.
Operations on MenuEntries
CreateEntry:
PROC [name: Rope.
ROPE, proc: ClickProc, clientData:
REF
ANY ←
NIL,
documentation: REF ANY ← NIL, fork: BOOL ← TRUE, guarded: BOOL ← FALSE]
RETURNS [entry: MenuEntry] ;
Create an item that can be added to a menu. 'name' is the text that will be displayed to the user, 'proc' is the procedure that will get called when the user invokes the menu, 'clientData' is arbitray data that will be passed to the proc, 'documentation' may either be a Rope.ROPE or a REF ClickProc and will either be displayed in the message window or called respectively when a guarded entry has its cover removed. 'fork' will FORK and Detach a separate process when the proc is called, 'guarded' menu items have a diagonal cross-hatch pattern over the text that is removed when the user clicks at the menu item. Only if the user clicks at a guarded menu item while the 'cover' is off will the proc be called.
CopyEntry:
PROC [oldEntry: MenuEntry]
RETURNS [newEntry: MenuEntry] =
INLINE {RETURN[NEW[MenuEntryRec ← oldEntry^]]} ;
SetGuarded:
PROC [entry: MenuEntry, guard:
BOOL] =
INLINE {entry.guarded ← guard; entry.guardState ← IF guard THEN guarded ELSE armed} ;
SetClientData:
PROC [entry: MenuEntry, newData:
REF
ANY]
RETURNS [oldData:
REF
ANY] =
INLINE {oldData ← entry.clientData; entry.clientData ← newData} ;
SetDocumentation:
PROC [entry: MenuEntry, newDoc:
REF
ANY]
RETURNS [oldDoc:
REF
ANY] =
INLINE {oldDoc ← entry.documentation; entry.documentation ← newDoc} ;
Operations on Menus
FindEntry:
PROC [menu: Menu, entryName: Rope.
ROPE]
RETURNS [entry: MenuEntry] ;
Search for an entry given the name. Will return NIL if target name not found.
AppendMenuEntry:
PROC [menu: Menu, entry: MenuEntry, line: MenuLine ← 0] ;
Add a new menu entry to the end of a line
InsertMenuEntry:
PROC [menu: Menu, entry: MenuEntry, line: MenuLine ← 0] ;
Add a new menu entry to the front of a line
ReplaceMenuEntry:
PROC [menu: Menu, oldEntry: MenuEntry, newEntry: MenuEntry ←
NIL] ;
Change an existing entry in a menu. If newEntry is NIL then the oldEntry will be deleted.
Will raise targetNotFound if target entry not found.
targetNotFound: SIGNAL ;
ChangeNumberOfLines:
PROC [menu: Menu, newLines: MenuLine] =
INLINE {menu.linesUsed ← newLines} ;
GetNumberOfLines:
PROC [menu: Menu]
RETURNS [lines: MenuLine] =
INLINE {RETURN[menu.linesUsed]} ;
SetLine:
PROC [menu: Menu, line: MenuLine, entryList: MenuEntry] =
INLINE {menu.lines[line] ← entryList; menu.linesUsed ← MAX[menu.linesUsed, line+1]} ;
GetLine:
PROC [menu: Menu, line: MenuLine]
RETURNS [entryList: MenuEntry] =
INLINE {RETURN[menu.lines[line]]} ;
Menu private stuff below; no user seviceable parts
MenuRec:
TYPE =
PRIVATE
RECORD [
lines: ARRAY MenuLine OF MenuEntry ← ALL[NIL],
x, y: INTEGER ← 0,
linesUsed: MenuLine ← 1,
lineInverted: MenuLine ← 0,
inverted: MenuEntry ← NIL
];
MenuEntryRec:
TYPE =
PRIVATE
MONITORED
RECORD [
-- 15 words
link: MenuEntry ← NIL,
name: Rope.ROPE,
proc: ClickProc,
width: INTEGER ← 0,
xPos: INTEGER ← 0,
clientData: REF ANY ← NIL,
documentation: REF ANY ← NIL,
fork: BOOL ← TRUE,
greyed: BOOL ← FALSE,
guarded: BOOL ← FALSE,
guardState: GuardState ← armed
];
GuardState: TYPE = { guarded, arming, armed };
armingTime: Process.Milliseconds = 100; -- cover removal time.
armedTime: Process.Milliseconds = 5000; -- unguarded interval.
END.