/* EXPORT->HGetEvent: return next relevant event in event queue */
HEventRec HGetEvent(Boolean anyEvent, void (*action)(void))
{
XEvent xev;
HEventRec hev;
Boolean found,dummy;
XFlush(theDisp); found = FALSE;
do {
if(XEventsQueued(theDisp, QueuedAfterFlush) > 0 || action==NULL){
XNextEvent(theDisp, &xev);
found = TRUE;
if (xev.xany.window==theWindow || anyEvent){
switch (xev.type) {
case ButtonPress:
hev.event = HMOUSEDOWN;
hev.x = xev.xbutton.x;
hev.y = xev.xbutton.y;
break;
case ButtonRelease:
hev.event = HMOUSEUP;
hev.x = xev.xbutton.x;
hev.y = xev.xbutton.y;
break;
case MotionNotify:
hev.event = HMOUSEMOVE;
hev.x = xev.xmotion.x;
hev.y = xev.xmotion.y;
break;
case KeyPress:
hev.event = HKEYPRESS;
hev.x = xev.xkey.x;
hev.y = xev.xkey.y;
DecodeKeyPress(&(xev.xkey), &hev);
break;
case KeyRelease:
hev.event = HKEYRELEASE;
hev.x = xev.xkey.x;
hev.y = xev.xkey.y;
DecodeKeyPress(&(xev.xkey), &hev);
break;
case Expose:
if (xev.xexpose.count==0)
hev.event = HREDRAW;
else
found = FALSE;
break;
default:
found = FALSE;
}
}
} else if (action!=NULL){
(*action)();
XFlush(theDisp);
/* execute a round-robin command to make sure that */
/* client doesnt get too far ahead of the server */
dummy = HMousePos(&hev.x,&hev.y);
}
} while (!found);
return hev;
}
// main routine
main(int argc, char **argv)
{
char string[BUFSIZ];
// connect to x-server
int screen;
Window rootwindow;
Display *display = ConnectToServer(NULL, screen, rootwindow);
if (display == NULL)
{
ERROR("connect to server failed.", EINVAL);
return(2);
}
// get basic colors
black = BlackPixel(display, screen);
white = WhitePixel(display, screen);
// create a window
Visual *visual = CopyFromParent;
int x = 10;
int y = 10;
int width = 300;
int height = 300;
Window window = OpenWindow(display,
rootwindow,
x, y, width, height,
black, white,
EVENT_MASK, visual);
// set hints for window
SetStandardHints(display, window, argv[0], argv[0],
x, y, width, height);
// create GC for drawing
GC gc = CreateGC(display, window, black, white);
// load a font
XFontStruct *font_struct =
LoadFont(display, FONT_NAME, FALLBACK_FONT_NAME);
// set up gc with font structure
XSetFont(display, gc, font_struct->fid);
// map window
XMapRaised(display, window);
XFlush(display);
// event loop: max of 20 events, then exit.
KeySym keysym;
XEvent event;
for (int done = False; done != True; )
{
XNextEvent(display, &event);
switch (event.type)
{
case Expose:
cout << "Expose: <x, y, w, h> = <";
cout << event.xexpose.x << ",";
cout << event.xexpose.y << ",";
cout << event.xexpose.width << ",";
cout << event.xexpose.height;
cout << ">" << endl;
if (event.xexpose.count == 0)
{
cout << "last expose event." << endl;
}
break;
case MapNotify:
cout << "MapNotify: window was mapped." << endl;
break;
case ButtonPress:
cout << "ButtonPress: ";
cout << ButtonIds[event.xbutton.button];
cout << " at <";
cout << event.xbutton.x << ",";
cout << event.xbutton.y << ">" << endl;
AppendKeyStateMessage(event.xbutton.state);
break;
case EnterNotify:
cout << "EnterNotify: pointer enters window" << endl;
break;
case LeaveNotify:
cout << "LeaveNotify: pointer enters window" << endl;
break;
case ButtonRelease:
cout << "ButtonRelease: ";
cout << ButtonIds[event.xbutton.button];
cout << " at <";
cout << event.xbutton.x << ",";
cout << event.xbutton.y << ">" << endl;
AppendKeyStateMessage(event.xbutton.state);
break;
case KeyPress:
done = DecodeKeyPress(&event.xkey, &keysym, string);
HandleKeyPress(&event.xkey, keysym, string);
break;
case ConfigureNotify:
cout << "ConfigureNotify: <x, y, w, h> = <";
cout << event.xconfigure.x << ",";
cout << event.xconfigure.y << ",";
cout << event.xconfigure.width << ",";
cout << event.xconfigure.height;
cout << ">" << endl;
break;
}
// redraw for all events.
if ( ! done) redraw(display, window, gc);
}
// close connection
XFreeFont(display, font_struct);
XCloseDisplay(display);
// all done
return(0);
}
// main entry point
main(int argc, char **argv)
{
// get command line options
int nextarg;
if (cmdopts(argc, argv, nextarg) != OK)
{
fprintf(stderr, "invalid command line option [%s].\n",
argv[nextarg]);
return(2);
}
// get data
if (getdata(argc, argv, nextarg) != OK)
{
fprintf(stderr, "unable to get data.");
return(2);
}
// connect to server
Display *xdisplay = NULL;
if (OpenDisplay(display, xdisplay) != OK)
{
fprintf(stderr, "unable to open display to server %s.\n",
XDisplayName(display));
return(2);
}
// get physical screen attributes
int xscreen;
unsigned int display_width, display_height;
if (GetDisplayAttributes(xdisplay, xscreen,
display_width, display_height) != OK)
{
fprintf(stderr, "unable to get display attributes.\n");
CloseDisplay(xdisplay);
return(2);
}
// determine window geometry and location
int window_width, window_height, window_x, window_y;
if (GetWindowGeometry(display_width, display_height,
window_width, window_height,
window_x, window_y) != OK)
{
fprintf(stderr, "unable to get window geometry.\n");
CloseDisplay(xdisplay);
return(2);
}
// default black and white pixels
unsigned long black = BlackPixel(xdisplay, xscreen);
unsigned long white = WhitePixel(xdisplay, xscreen);
// get pseudo-color display, if any
int window_depth;
Visual *window_visual;
if (GetPseudoColorVisual(xdisplay, xscreen,
window_visual, window_depth) != OK)
{
fprintf(stderr, "unable to get a color visual.\n");
CloseDisplay(xdisplay);
return(2);
}
// create a window
unsigned int window_border_width = 4;
Window root_window = RootWindow(xdisplay, xscreen);
window_visual=CopyFromParent;
window_depth=CopyFromParent;
Window window = CreateWindow(
xdisplay, root_window,
window_x, window_y, window_width, window_height,
black, white, EventMask,
window_visual, window_border_width, window_depth);
// set size hints
if (SetSizeHints(xdisplay, window,
window_x, window_y, window_width, window_height) != OK)
{
fprintf(stderr, "unable to set window size hints.\n");
CloseDisplay(xdisplay);
return(2);
}
// set window name
if (SetWindowName(xdisplay, window, title) != OK)
{
fprintf(stderr, "unable to set window title.\n");
CloseDisplay(xdisplay);
return(2);
}
// set class hints
if (SetClassHints(xdisplay, window, argv[0], argv[0]) != OK)
{
fprintf(stderr, "unable to set class hints.\n");
CloseDisplay(xdisplay);
return(2);
}
// set other window manager hints
int initstate =
(strcmp(iconic, "YES") == 0) ? IconicState : NormalState;
if (SetWMHints(xdisplay, window, initstate) != OK)
{
fprintf(stderr, "unable to set WM hints.\n");
CloseDisplay(xdisplay);
return(2);
}
// set up color map for window
Colormap window_colormap;
if (SetUpColorMap(xdisplay, xscreen,
window, window_visual, window_colormap) != OK)
{
fprintf(stderr, "unable to set up a color map.\n");
CloseDisplay(xdisplay);
return(2);
}
// allocate colors for background and foreground
unsigned long window_background =
AllocateColorByName(xdisplay, window_colormap,
background, white);
unsigned long window_foreground =
AllocateColorByName(xdisplay, window_colormap,
foreground, black);
// get font for writing
XFontStruct *xfont = LoadFont(xdisplay, font, "fixed");
if (xfont == NULL)
{
fprintf(stderr, "unable to load font.\n");
CloseDisplay(xdisplay);
return(2);
}
// create GC for drawing
GC gc = CreateGC(xdisplay, window, xfont,
window_foreground, window_background);
GC xor_gc = CreateXorGC(xdisplay, window, xfont,
window_foreground, window_background);
// map window
XMapRaised(xdisplay, window);
XFlush(xdisplay);
// event loop
int start_x = -1;
int start_y = -1;
int last_x = -1;
int last_y = -1;
XEvent event;
KeySym keysym;
char string[BUFSIZ];
for (int done = 0; !done; )
{
XNextEvent(xdisplay, &event);
switch (event.type)
{
case Expose:
if (event.xexpose.count == 0)
{
redraw(xdisplay, window, gc, xfont,
window_width, window_height);
}
break;
case ConfigureNotify:
window_x = event.xconfigure.x;
window_y = event.xconfigure.y;
window_width = event.xconfigure.width;
window_height = event.xconfigure.height;
break;
case KeyPress:
done = DecodeKeyPress(&event.xkey, &keysym, string);
break;
case MappingNotify:
XRefreshKeyboardMapping(&event.xmapping);
break;
case ButtonPress:
if (event.xbutton.button == Button1)
{
start_x = event.xbutton.x;
start_y = event.xbutton.y;
last_x = start_x;
last_y = start_y;
DrawBox(xdisplay, window, xor_gc,
start_x, start_y, last_x, last_y);
XFlush(xdisplay);
}
break;
case ButtonRelease:
if (event.xbutton.button == Button1)
{
if (start_x != last_x && start_y != last_y)
{
DrawBox(xdisplay, window, xor_gc,
start_x, start_y,
last_x, last_y);
XFlush(xdisplay);
UpdateLimits(start_x, start_y,
last_x, last_y,
window_width, window_height);
XClearWindow(xdisplay, window);
XFlush(xdisplay);
redraw(xdisplay, window, gc, xfont,
window_width, window_height);
XFlush(xdisplay);
}
start_x = -1;
start_y = -1;
last_x = -1;
last_y = -1;
}
else
{
// reset to original values.
rminxval = reset_rminxval;
rmaxxval = reset_rmaxxval;
rminyval = reset_rminyval;
rmaxyval = reset_rmaxyval;
XClearWindow(xdisplay, window);
XFlush(xdisplay);
redraw(xdisplay, window, gc, xfont,
window_width, window_height);
XFlush(xdisplay);
}
break;
case MotionNotify:
if (event.xbutton.button == Button1)
{
DrawBox(xdisplay, window, xor_gc,
start_x, start_y, last_x, last_y);
last_x = event.xmotion.x;
last_y = event.xmotion.y;
DrawBox(xdisplay, window, xor_gc,
start_x, start_y, last_x, last_y);
XFlush(xdisplay);
}
break;
}
}
// close display
CloseDisplay(xdisplay);
// all done
return(0);
}