examples/howto-drag-and-drop.cxx

   1 //
   2 // "$Id: howto-drag-and-drop.cxx 8221 2011-01-08 18:58:50Z greg.ercolano $"
   3 //
   4 //     A simple demo of drag+drop with FLTK.
   5 //     Originally from erco's cheat sheet, permission by author.
   6 //     Inspired by Michael Sephton's original example posted on fltk.general.
   7 //
   8 //     When you run the program, just drag the red square over
   9 //     to the green square to show a 'drag and drop' sequence.
  10 //
  11 // Copyright 1998-2010 by Bill Spitzak and others.
  12 //
  13 // This library is free software; you can redistribute it and/or
  14 // modify it under the terms of the GNU Library General Public
  15 // License as published by the Free Software Foundation; either
  16 // version 2 of the License, or (at your option) any later version.
  17 //
  18 // This library is distributed in the hope that it will be useful,
  19 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21 // Library General Public License for more details.
  22 //
  23 // You should have received a copy of the GNU Library General Public
  24 // License along with this library; if not, write to the Free Software
  25 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  26 // USA.
  27 //
  28 // Please report all bugs and problems on the following page:
  29 //
  30 //     http://www.fltk.org/str.php
  31 //
  32
  33 #include <stdio.h>
  34 #include <FL/Fl.H>
  35 #include <FL/Fl_Window.H>
  36 #include <FL/Fl_Box.H>
  37
  38 // SIMPLE SENDER CLASS
  39 class Sender : public Fl_Box {
  40 public:
  41   // Ctor
  42   Sender(int x,int y,int w,int h) : Fl_Box(x,y,w,h) {
  43     box(FL_FLAT_BOX);
  44     color(9);
  45     label("Drag\nfrom\nhere..");
  46   }
  47   // Sender event handler
  48   int handle(int event) {
  49     int ret = Fl_Box::handle(event);
  50     switch ( event ) {
  51       case FL_PUSH: {             // do 'copy/dnd' when someone clicks on box
  52         const char *msg = "It works!";
  53         Fl::copy(msg,strlen(msg),0);
  54         Fl::dnd();
  55         ret = 1;
  56         break;
  57       }
  58     }
  59     return(ret);
  60   }
  61 };
  62 // SIMPLE RECEIVER CLASS
  63 class Receiver : public Fl_Box {
  64 public:
  65   // Ctor
  66   Receiver(int x,int y,int w,int h) : Fl_Box(x,y,w,h) {
  67     box(FL_FLAT_BOX); color(10); label("..to\nhere");
  68   }
  69   // Receiver event handler
  70   int handle(int event) {
  71     int ret = Fl_Box::handle(event);
  72     switch ( event ) {
  73       case FL_DND_ENTER:          // return(1) for these events to 'accept' dnd
  74       case FL_DND_DRAG:
  75       case FL_DND_RELEASE:
  76         ret = 1;
  77         break;
  78       case FL_PASTE:              // handle actual drop (paste) operation
  79         label(Fl::event_text());
  80         fprintf(stderr, "Pasted '%s'\n", Fl::event_text());
  81         ret = 1;
  82         break;
  83     }
  84     return(ret);
  85   }
  86 };
  87 int main(int argc, char **argv) {
  88   // Create sender window and widget
  89   Fl_Window win_a(0,0,200,100,"Sender");
  90   Sender a(0,0,100,100);
  91   win_a.end();
  92   win_a.show();
  93   // Create receiver window and widget
  94   Fl_Window win_b(400,0,200,100,"Receiver");
  95   Receiver b(100,0,100,100);
  96   win_b.end();
  97   win_b.show();
  98   return(Fl::run());
  99 }
 100
 101 //
 102 // End of "$Id: howto-drag-and-drop.cxx 8221 2011-01-08 18:58:50Z greg.ercolano $".
 103 //