Window creation/X11: Difference between revisions

from wiki.freepascal.org/X11#Examples. Seems to be the translation of C.

Compiled with Freepascal 2.6.4-32

<lang pascal>program xshowwindow;

{$mode objfpc}{$H+}

uses

xlib, x, ctypes;

procedure ModalShowX11Window(AMsg: string);

var

d: PDisplay;

w: TWindow;

e: TXEvent;

msg: PChar;

s: cint;

begin

msg := PChar(AMsg);

{ open connection with the server }

d := XOpenDisplay(nil);

if (d = nil) then

begin

WriteLn('[ModalShowX11Window] Cannot open display');

exit;

end;

s := DefaultScreen(d);

{ create window }

w := XCreateSimpleWindow(d, RootWindow(d, s), 10, 10, 100, 50, 1,

BlackPixel(d, s), WhitePixel(d, s));

{ select kind of events we are interested in }

XSelectInput(d, w, ExposureMask or KeyPressMask);

{ map (show) the window }

XMapWindow(d, w);

{ event loop }

while (True) do

begin

XNextEvent(d, @e);

{ draw or redraw the window }

if (e._type = Expose) then

begin

XFillRectangle(d, w, DefaultGC(d, s), 0, 10, 100, 3);

XFillRectangle(d, w, DefaultGC(d, s), 0, 30, 100, 3);

XDrawString (d, w, DefaultGC(d, s), 5, 25, msg, strlen(msg));

end;

{ exit on key press }

if (e._type = KeyPress) then Break;

end;

{ close connection to server }

XCloseDisplay(d);

end;

begin

ModalShowX11Window('Hello, World!');

end.

</lang>