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- 4.49.1.13 -
Standard Units
Mouse Unit
Mouse Unit Procedures and Functions

SetMouseHandler procedure

Targets: MS-DOS, Win32 console


Mouse Unit

Installs a Pascal interrupt-driven user's mouse handler (Hnd).

Declaration:
procedure SetMouseHandler (Mask: DWord;
                            Procedure Hnd (Mask,
                            Buttons,
                            X, Y,
                            MovX, MovY: System.Word));
Remarks:
The Mask parameter defines the classes of the events that call the handler; its format corresponds to the function 0Ch (INT 33h). When Hnd is called the Mask parameter contains the mask with the event type that occurred; Buttons contain the mask of the currently pressed buttons; X and Y contain the cursor's absolute position, and MovX and MovY contain the relative (signed) change of the last cursor position [negative numbers mean left or down; positive mean right or up]. These values are given in mouse position units; to convert to symbols, they need to be divided by 8.

Using SetMouseHandler you can install several handlers with different masks without having to clear previous handlers.

Event Mask (events which you want sent to your handler)
 bit 0 = mouse movement           (Mask = $01)
 bit 1 = left button pressed      (Mask = $02)
 bit 2 = left button released     (Mask = $04)
 bit 3 = right button pressed     (Mask = $08)
 bit 4 = right button released    (Mask = $10)
 bit 5 = center button pressed    (Mask = $20)
 bit 6 = center button released   (Mask = $40)
         all events:      Mask = 007fH
         disable handler: Mask = 0000H
See also:
ClearMouseHandler

Example:
program Test;
{$ifndef __DOS__}
  {$ifndef __WIN32__}
    This program can be compiled for MS-DOS and Win32 console targets only
  {$endif}
{$endif}
uses
  CRT, Mouse;
var
  isExit: Boolean := FALSE;
  X, Y:   DWord;
  star:   Word := $0F2A;
  space:  Word := $0F00;
 
procedure MyHnd(Mask, Buttons, X, Y, MovX, MovY: System.Word);
begin
  GotoXY(1, 2);
  Writeln('XPos = ', MickyToText(X),', YPos = ', MickyToText(Y), '  ');
end;
 
begin
  ClrScr;
  Writeln('Press Esc to exit');
  HideCursor;
  InitMouse;
  SetMouseHandler($FFFF, MyHnd);
  repeat
    X := MickyToText(GetMouseX) + 1;
    Y := MickyToText(GetMouseY) + 1;
    if (LeftButtonPressed) and (Y > 2) and
       (Y < 25) then  WriteAttr (X, Y, Star, 1);
    if (RightButtonPressed) and (Y > 2) and
       (Y < 25) then WriteAttr (X, Y, Space, 1);
   if Keypressed then 
     isExit := ReadKey = #27;
  until isExit;
  ShowCursor;
  DoneMouse;
end.



Previous: RightButtonPressed function To the Table of Content Next: SetMousePos procedure
RightButtonPressed function Table of Content SetMousePos procedure

- 4.49.1.13 -