Unable to catch ButtonRelease event
आशीष शुक्ला
I'm learning to program in Xlib, and written a program in C on Fedora
Core 5 (AMD64) Linux. The objective of my program is to close its
window, when a mouse button is released on its window.
-- begin dump --
#include <X11/Xlib.h>
#include <stdio.h>
#include <stdlib.h>
#define WIDTH 300
#define HEIGHT 200
#define BORDER_WIDTH 12
static void main_loop(Display*);
int
main()
{
Display* display = NULL;
int scr_height, scr_width, scr_num;
Window win_root, win_me;
unsigned long pix_white, pix_black;
display = XOpenDisplay(NULL);
if(display == NULL)
{
fprintf(stderr, "Can't connect to X server: %s\n",
XDisplayName(NULL));
exit(-1);
}
scr_num = DefaultScreen(display);
scr_width = DisplayWidth(display, scr_num);
scr_height = DisplayHeight(display, scr_num);
win_root = RootWindow(display, scr_num);
pix_white = WhitePixel(display, scr_num);
pix_black = BlackPixel(display, scr_num);
win_me = XCreateSimpleWindow(display, win_root,
0, 0, WIDTH, HEIGHT, BORDER_WIDTH, pix_black,
pix_white);
XMapWindow(display, win_me);
XSelectInput(display, win_me, ExposureMask | ButtonReleaseMask);
main_loop(display);
XUnmapWindow(display, win_me);
XDestroyWindow(display, win_me);
XCloseDisplay(display);
}
void
main_loop(Display* display)
{
XEvent event;
int running = 1;
while(running)
{
XNextEvent(display, &event);
printf("event, type=%d\n", event.type);
switch(event.type)
{
case Expose:
break;
case ButtonRelease:
printf("released\n");
running = 0;
break;
default:
fprintf(stderr, "unexpected event: %d\n",
event.type);
}
}
}
-- end dump --
Even after releasing mouse button several times on the window, I'm
unable to receive a single ButtonRelease event. Can anybody tell me,
what I'm doing wrong here ?
Thanks in advance,
Ashish Shukla
--
http://www.geocities.com/wah_java_dotnet/
Fred Kleinschmidt
"???? ??????" <wah...@gmail.com> wrote in message
news:1147858340....@i40g2000cwc.googlegroups.com...
Are you pressing the button while the cursor is in the window, then
releasing it? Or are you pressing the button OUTSIDE the window,
moving into the window and then releasing it? For the latter
case it will not work. That is because the window in which you
press the button "grabs" the next button release event.
--
Fred L. Kleinschmidt
Boeing Associate Technical Fellow
Technical Architect, Software Reuse Project
आशीष शुक्ला
First of all thanks for replying.
After, changing the following line
-- begin dump --
XSelectInput(display, win_me, ExposureMask | ButtonReleaseMask);
-- end dump --
to
-- begin dump --
XSelectInput(display, win_me, ExposureMask | ButtonReleaseMask |
ButtonPressMask);
-- end dump --
my code works fine. and produces the following output:
-- begin dump --
event, type=12
event, type=12
event, type=12
event, type=4
unexpected event: 4
event, type=5
released
-- end dump --
Previously (before changing) it produces this (window is closed from
the close button in the win decoration):
-- begin dump --
event, type=12
event, type=12
event, type=12
X connection to :0.0 broken (explicit kill or server shutdown).
-- end dump --
I've even tried changing window managers (GNOME and KDE).
> Works fine for me as you wrote it.
> Are you pressing the button while the cursor is in the window, then
> releasing it? Or are you pressing the button OUTSIDE the window,
> moving into the window and then releasing it? For the latter
> case it will not work. That is because the window in which you
> press the button "grabs" the next button release event.
Well, I was clicking in former way, i.e. pressing and releasing button
in the same window. BTW, which you're on which platform and running
which X server.
This is my command line I used to compile with:
-- begin dump --
cc -o paint paint.c -lX11
-- end dump --
And output of "X -version" is below:
-- begin dump --
X Window System Version 7.0.0
Release Date: 21 December 2005
X Protocol Version 11, Revision 0, Release 7.0
Build Operating System:Linux 2.6.9-22.18.bz155725.ELsmp x86_64Red Hat,
Inc.
Current Operating System: Linux myhome 2.6.16-1.2111_FC5 #1 SMP Thu May
4 21:16:04 EDT 2006 x86_64
Build Date: 02 May 2006
Before reporting problems, check http://wiki.x.org
to make sure that you have the latest version.
Module Loader present
-- end dump --
Is this a bug in my X server ??
> --
> Fred L. Kleinschmidt
> Boeing Associate Technical Fellow
> Technical Architect, Software Reuse Project
Thanks again,
Fred Kleinschmidt
exceed,
and they all work as expected - no need for the ButtonPressMask if
press/release
is in the same window.
It may be a bug. However, you will almost always want to mask for
both press and release in your window. on PRESS you set a flag that
gets ready to act, then on RELEASE check the flag. If set, act.
Then always reset the flag.
आशीष शुक्ला
Fred Kleinschmidt wrote:
> I tried it on 8 different Unix/Linux platforms, plus Cygwin on a PC using
> exceed,
> and they all work as expected - no need for the ButtonPressMask if
> press/release
> is in the same window.
I'm grateful to you for this. And sorry for any inconvenience.
>
> It may be a bug. However, you will almost always want to mask for
> both press and release in your window. on PRESS you set a flag that
> gets ready to act, then on RELEASE check the flag. If set, act.
> Then always reset the flag.
Anyways, I've tried it also on FreeBSD 6.0 (AMD64), and the same
result.
-- begin dump --
X Window System Version 6.8.2
Release Date: 9 February 2005
X Protocol Version 11, Revision 0, Release 6.8.2
Build Operating System: FreeBSD 6.0 amd64 [ELF]
Current Operating System: FreeBSD myhome 6.0-RELEASE FreeBSD
6.0-RELEASE #0: Sat Feb 11 20:41:16 IST 2006
wahjava@myhome:/usr/obj/usr/src/sys/MYHOME amd64
Build Date: 13 October 2005
Before reporting problems, check http://wiki.X.Org
to make sure that you have the latest version.
Module Loader present
-- end dump --
It will be great if you post versions (and architectures) of X servers.
Do you suspect any portability (across architecture, i.e. 32bit to 64
bit) error, coz I think all my OSs are 64bit (AMD64) and one of the OS
mentioned (Cygwin on Windows, is 32-bit).
I'll reinspect my source code for any portability issues.
> --
> Fred L. Kleinschmidt
> Boeing Associate Technical Fellow
> Technical Architect, Software Reuse Project
But anyways, thanks for your co-operation.
आशीष शुक्ला
I've also tried the above program on Ubuntu Linux "Breezy" (AMD64) but
same result.Anyways here is my xorg.conf , may be that might help in
troubleshoot:
-- begin dump --
# Xorg configuration created by system-config-display
Section "ServerLayout"
Identifier "single head configuration"
Screen 0 "Screen0" 0 0
InputDevice "Mouse0" "CorePointer"
InputDevice "Keyboard0" "CoreKeyboard"
EndSection
Section "Files"
FontPath "unix/:7100"
EndSection
Section "Module"
Load "dbe"
Load "extmod"
Load "fbdevhw"
Load "glx"
Load "record"
Load "freetype"
Load "type1"
Load "dri"
EndSection
Section "InputDevice"
Identifier "Keyboard0"
Driver "kbd"
Option "XkbModel" "pc105"
Option "XkbLayout" "us"
EndSection
Section "InputDevice"
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "IMPS/2"
Option "Device" "/dev/input/mice"
Option "ZAxisMapping" "4 5"
Option "Emulate3Buttons" "yes"
EndSection
Section "Monitor"
Identifier "Monitor0"
VendorName "Monitor Vendor"
ModelName "Monitor 1024x768"
HorizSync 31.5 - 54.0
VertRefresh 50.0 - 120.0
Option "dpms"
Option "SyncOnGreen"
Modeline "1024x768@60" 0 1024 0 0 0 768 0 0 0
EndSection
Section "Device"
Identifier "Videocard0"
Driver "i810"
VendorName "Videocard vendor"
BoardName "Intel Corporation 945G Integrated Graphics Controller"
EndSection
Section "Screen"
Identifier "Screen0"
Device "Videocard0"
Monitor "Monitor0"
DefaultDepth 24
SubSection "Display"
Viewport 0 0
Depth 16
Modes "800x600" "640x480"
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 24
Modes "1024x768" "800x600" "640x480"
EndSubSection
EndSection
Section "DRI"
Mode 0666
EndSection
Section "Extensions"
Option "Composite" "Enable"
EndSection
-- end dump --
All the X servers I've tested on, have identical configuration files
except on FreeBSD (AMD64) where I'm using "vesa" driver.
आशीष शुक्ला
Well that was the bug in the Window Managers metacity, kwin, mwm. When
I ran the program without any window manager it worked fine.
Thanks