src/Fl_grab.cxx

   1 //
   2 // "$Id: Fl_grab.cxx 8055 2010-12-18 22:31:01Z manolo $"
   3 //
   4 // Grab/release code for the Fast Light Tool Kit (FLTK).
   5 //
   6 // Copyright 1998-2010 by Bill Spitzak and others.
   7 //
   8 // This library is free software; you can redistribute it and/or
   9 // modify it under the terms of the GNU Library General Public
  10 // License as published by the Free Software Foundation; either
  11 // version 2 of the License, or (at your option) any later version.
  12 //
  13 // This library is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16 // Library General Public License for more details.
  17 //
  18 // You should have received a copy of the GNU Library General Public
  19 // License along with this library; if not, write to the Free Software
  20 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  21 // USA.
  22 //
  23 // Please report all bugs and problems on the following page:
  24 //
  25 //     http://www.fltk.org/str.php
  26 //
  27
  28 #include <config.h>
  29 #include <FL/Fl.H>
  30 #include <FL/x.H>
  31
  32 ////////////////////////////////////////////////////////////////
  33 // "Grab" is done while menu systems are up.  This has several effects:
  34 // Events are all sent to the "grab window", which does not even
  35 // have to be displayed (and in the case of Fl_Menu.cxx it isn't).
  36 // The system is also told to "grab" events and send them to this app.
  37 // This also modifies how Fl_Window::show() works, on X it turns on
  38 // override_redirect, it does similar things on WIN32.
  39
  40 extern void fl_fix_focus(); // in Fl.cxx
  41
  42 #ifdef WIN32
  43 // We have to keep track of whether we have captured the mouse, since
  44 // MSWindows shows little respect for this... Grep for fl_capture to
  45 // see where and how this is used.
  46 extern HWND fl_capture;
  47 #endif
  48
  49 #ifdef __APPLE__
  50 extern void *fl_capture;
  51 #endif
  52
  53 void Fl::grab(Fl_Window* win) {
  54   if (win) {
  55     if (!grab_) {
  56 #ifdef WIN32
  57       SetActiveWindow(fl_capture = fl_xid(first_window()));
  58       SetCapture(fl_capture);
  59 #elif defined(__APPLE__)
  60       fl_capture = Fl_X::i(first_window())->xid;
  61       Fl_X::i(first_window())->set_key_window();
  62 #else
  63       XGrabPointer(fl_display,
  64                    fl_xid(first_window()),
  65                    1,
  66                    ButtonPressMask|ButtonReleaseMask|
  67                    ButtonMotionMask|PointerMotionMask,
  68                    GrabModeAsync,
  69                    GrabModeAsync,
  70                    None,
  71                    0,
  72                    fl_event_time);
  73       XGrabKeyboard(fl_display,
  74                     fl_xid(first_window()),
  75                     1,
  76                     GrabModeAsync,
  77                     GrabModeAsync,
  78                     fl_event_time);
  79 #endif
  80     }
  81     grab_ = win;
  82   } else {
  83     if (grab_) {
  84 #ifdef WIN32
  85       fl_capture = 0;
  86       ReleaseCapture();
  87 #elif defined(__APPLE__)
  88       fl_capture = 0;
  89 #else
  90       XUngrabKeyboard(fl_display, fl_event_time);
  91       XUngrabPointer(fl_display, fl_event_time);
  92       // this flush is done in case the picked menu item goes into
  93       // an infinite loop, so we don't leave the X server locked up:
  94       XFlush(fl_display);
  95 #endif
  96       grab_ = 0;
  97       fl_fix_focus();
  98     }
  99   }
 100 }
 101
 102 //
 103 // End of "$Id: Fl_grab.cxx 8055 2010-12-18 22:31:01Z manolo $".
 104 //