1 //
2 // Drag & Drop code for the Fast Light Tool Kit (FLTK).
3 //
4 // Copyright 1998-2021 by Bill Spitzak and others.
5 //
6 // This library is free software. Distribution and use rights are outlined in
7 // the file "COPYING" which should have been included with this file. If this
8 // file is missing or damaged, see the license at:
9 //
10 // https://www.fltk.org/COPYING.php
11 //
12 // Please see the following page on how to report bugs and issues:
13 //
14 // https://www.fltk.org/bugs.php
15 //
16
17 #include <FL/Fl.H>
18 #include <FL/Fl_Window.H>
19 #include <FL/x.H>
20 #include "flstring.h"
21
22
23 extern Atom fl_XdndAware;
24 extern Atom fl_XdndSelection;
25 extern Atom fl_XdndEnter;
26 extern Atom fl_XdndTypeList;
27 extern Atom fl_XdndPosition;
28 extern Atom fl_XdndLeave;
29 extern Atom fl_XdndDrop;
30 extern Atom fl_XdndStatus;
31 extern Atom fl_XdndActionCopy;
32 extern Atom fl_XdndFinished;
33 extern Atom fl_XdndURIList;
34 extern Atom fl_XaUtf8String;
35
36 extern char fl_i_own_selection[2];
37 extern char *fl_selection_buffer[2];
38
39 extern void fl_sendClientMessage(Window window, Atom message,
40 unsigned long d0,
41 unsigned long d1=0,
42 unsigned long d2=0,
43 unsigned long d3=0,
44 unsigned long d4=0);
45
46 // return version # of Xdnd this window supports. Also change the
47 // window to the proxy if it uses a proxy:
dnd_aware(Window & window)48 static int dnd_aware(Window& window) {
49 Atom actual; int format; unsigned long count, remaining;
50 unsigned char *data = 0;
51 XGetWindowProperty(fl_display, window, fl_XdndAware,
52 0, 4, False, XA_ATOM,
53 &actual, &format,
54 &count, &remaining, &data);
55 int ret = 0;
56 if (actual == XA_ATOM && format==32 && count && data)
57 ret = int(*(Atom*)data);
58 if (data) { XFree(data); data = 0; }
59 return ret;
60 }
61
grabfunc(int event)62 static int grabfunc(int event) {
63 if (event == FL_RELEASE) Fl::pushed(0);
64 return 0;
65 }
66
67 extern int (*fl_local_grab)(int); // in Fl.cxx
68
69 // send an event to an fltk window belonging to this program:
local_handle(int event,Fl_Window * window)70 static int local_handle(int event, Fl_Window* window) {
71 fl_local_grab = 0;
72 Fl::e_x = Fl::e_x_root-window->x();
73 Fl::e_y = Fl::e_y_root-window->y();
74 int ret = Fl::handle(event,window);
75 fl_local_grab = grabfunc;
76 return ret;
77 }
78
dnd()79 int Fl::dnd() {
80 Fl_Window *source_fl_win = Fl::first_window();
81 Fl::first_window()->cursor(FL_CURSOR_MOVE);
82 Window source_window = fl_xid(Fl::first_window());
83 fl_local_grab = grabfunc;
84 Window target_window = 0;
85 Fl_Window* local_window = 0;
86 int dndversion = 4; int dest_x, dest_y;
87 XSetSelectionOwner(fl_display, fl_XdndSelection, fl_message_window, fl_event_time);
88
89 while (Fl::pushed()) {
90 // figure out what window we are pointing at:
91 Window new_window = 0; int new_version = 0;
92 Fl_Window* new_local_window = 0;
93 for (Window child = RootWindow(fl_display, fl_screen);;) {
94 Window root; unsigned int junk3;
95 XQueryPointer(fl_display, child, &root, &child,
96 &e_x_root, &e_y_root, &dest_x, &dest_y, &junk3);
97 if (!child) {
98 if (!new_window && (new_version = dnd_aware(root))) new_window = root;
99 break;
100 }
101 new_window = child;
102 if ((new_local_window = fl_find(child))) break;
103 if ((new_version = dnd_aware(new_window))) break;
104 }
105
106 if (new_window != target_window) {
107 if (local_window) {
108 local_handle(FL_DND_LEAVE, local_window);
109 } else if (dndversion) {
110 fl_sendClientMessage(target_window, fl_XdndLeave, source_window);
111 }
112 dndversion = new_version;
113 target_window = new_window;
114 local_window = new_local_window;
115 if (local_window) {
116 local_handle(FL_DND_ENTER, local_window);
117 } else if (dndversion) {
118 // Send an X-DND message to the target window. In order to
119 // support dragging of files/URLs as well as arbitrary text,
120 // we look at the selection buffer - if the buffer starts
121 // with a common URI scheme, does not contain spaces, and
122 // contains at least one CR LF, then we flag the data as
123 // both a URI list (MIME media type "text/uri-list") and
124 // plain text. Otherwise, we just say it is plain text.
125 if ((!strncmp(fl_selection_buffer[0], "file:///", 8) ||
126 !strncmp(fl_selection_buffer[0], "ftp://", 6) ||
127 !strncmp(fl_selection_buffer[0], "http://", 7) ||
128 !strncmp(fl_selection_buffer[0], "https://", 8) ||
129 !strncmp(fl_selection_buffer[0], "ipp://", 6) ||
130 !strncmp(fl_selection_buffer[0], "ldap:", 5) ||
131 !strncmp(fl_selection_buffer[0], "mailto:", 7) ||
132 !strncmp(fl_selection_buffer[0], "news:", 5) ||
133 !strncmp(fl_selection_buffer[0], "smb://", 6)) &&
134 !strchr(fl_selection_buffer[0], ' ') &&
135 strstr(fl_selection_buffer[0], "\r\n")) {
136 // Send file/URI list...
137 fl_sendClientMessage(target_window, fl_XdndEnter, source_window, dndversion<<24,
138 fl_XdndURIList, fl_XaUtf8String, XA_STRING);
139 } else {
140 // Send plain text...
141 fl_sendClientMessage(target_window, fl_XdndEnter, source_window, dndversion<<24,
142 fl_XaUtf8String, XA_STRING, 0);
143 }
144 }
145 }
146 if (local_window) {
147 local_handle(FL_DND_DRAG, local_window);
148 } else if (dndversion) {
149 fl_sendClientMessage(target_window, fl_XdndPosition, source_window,
150 0, (e_x_root<<16)|e_y_root, fl_event_time,
151 fl_XdndActionCopy);
152 }
153 Fl::wait();
154 }
155
156 if (local_window) {
157 fl_i_own_selection[0] = 1;
158 if (local_handle(FL_DND_RELEASE, local_window)) paste(*belowmouse(), 0);
159 } else if (dndversion) {
160 fl_sendClientMessage(target_window, fl_XdndDrop, source_window,
161 0, fl_event_time);
162 } else if (target_window) {
163 // fake a drop by clicking the middle mouse button:
164 XButtonEvent msg;
165 msg.type = ButtonPress;
166 msg.window = target_window;
167 msg.root = RootWindow(fl_display, fl_screen);
168 msg.subwindow = 0;
169 msg.time = fl_event_time+1;
170 msg.x = dest_x;
171 msg.y = dest_y;
172 msg.x_root = Fl::e_x_root;
173 msg.y_root = Fl::e_y_root;
174 msg.state = 0x0;
175 msg.button = Button2;
176 XSendEvent(fl_display, target_window, False, 0L, (XEvent*)&msg);
177 msg.time++;
178 msg.state = 0x200;
179 msg.type = ButtonRelease;
180 XSendEvent(fl_display, target_window, False, 0L, (XEvent*)&msg);
181 }
182
183 fl_local_grab = 0;
184 source_fl_win->cursor(FL_CURSOR_DEFAULT);
185 return 1;
186 }
187
188
189 //
190 // End of "$Id$".
191 //
192