diff options
| -rw-r--r-- | examples/Makefile | 1 | ||||
| -rw-r--r-- | examples/howto-remap-numpad-keyboard-keys.cxx | 87 |
2 files changed, 88 insertions, 0 deletions
diff --git a/examples/Makefile b/examples/Makefile index 7fb5c3490..6bc8d305b 100644 --- a/examples/Makefile +++ b/examples/Makefile @@ -14,6 +14,7 @@ ALL = browser-simple$(EXEEXT) \ howto-drag-and-drop$(EXEEXT) \ howto-menu-with-images$(EXEEXT) \ howto-parse-args$(EXEEXT) \ + howto-remap-numpad-keyboard-keys$(EXEEXT) \ howto-simple-svg$(EXEEXT) \ howto-text-over-image-button$(EXEEXT) \ menubar-add$(EXEEXT) \ diff --git a/examples/howto-remap-numpad-keyboard-keys.cxx b/examples/howto-remap-numpad-keyboard-keys.cxx new file mode 100644 index 000000000..049b8e203 --- /dev/null +++ b/examples/howto-remap-numpad-keyboard-keys.cxx @@ -0,0 +1,87 @@ +// vim: autoindent tabstop=8 shiftwidth=2 expandtab softtabstop=2 +// +// "$Id$" +// +// Demonstrate keyboard remapping: Force number pad to type numbers even if NumLock off +// +// DESCRIPTION +// ----------- +// This demonstrates several important things: +// +// o How to use the global event dispatcher function Fl::event_dispatch() +// +// o How to remap keyboard events +// +// o How to use Fl::event_original_key() to easily ensure the dual purpose +// numeric keypad keys generate only numbers even if NumLock is off, +// without affecting the dedicated Home/End/etc keys. +// +// Use of Fl::event_original_key() ensures someone hitting e.g. "7/Home" key +// returns FL_KP+'7', and not FL_Home, while allowing the dedicated "Home" key +// to still generate FL_Home. This allows users to use the "Home" and "End" +// keys to navigate the buffer, while "7/Home" and "1/End" always type numbers. +// +// This demo based on fltk.general thread entitled "keyboard mapping", Aug 2019. +// +// * * * +// +// Copyright 1998-2017 by Bill Spitzak and others. +// +// This library is free software. Distribution and use rights are outlined in +// the file "COPYING" which should have been included with this file. If this +// file is missing or damaged, see the license at: +// +// http://www.fltk.org/COPYING.php +// +// Please report all bugs and problems on the following page: +// +// http://www.fltk.org/str.php +// + +#include <FL/Fl.H> +#include <FL/Fl_Double_Window.H> +#include <FL/Fl_Input.H> +#include <FL/Fl_Check_Button.H> + +// +Fl_Check_Button *G_checkbut = 0; + +// Global event handler: FLTK calls this after event translation. It's up to us +// to call Fl::handle_(e,w) to actually deliver the event to the widgets. If we +// don't and just return, the event will be dropped. See docs for more. +// +int MyHandler(int e, Fl_Window *w) { + // Remapping disabled? Early exit.. + if ( G_checkbut->value() == 0 ) return Fl::handle_(e, w); + // Keyboard key pressed? See if we should remap.. + if ( e == FL_KEYDOWN || e == FL_KEYUP) { + // Get FLTK keycode /before/ NumLock state is applied (see above DESCRIPTION) + int keycode = Fl::event_original_key(); // get keycode before FLTK applies NumLock + if ( keycode >= FL_KP && keycode <= FL_KP_Last ) { // keypad key pressed? + static char buf[2]; // static: we don't want buffer to go out of scope + buf[0] = char(keycode - FL_KP); // convert keypad keycode -> ascii + buf[1] = 0; // terminate string (for safety) + Fl::e_text = buf; // point to our static buffer + Fl::e_length = 1; // only first char relevant + } + } + return Fl::handle_(e, w); // let FLTK deliver event to widgets +} + +int main(int argc, char *argv[]) { + Fl_Double_Window *win = new Fl_Double_Window(400, 150, "Keyboard Translation Test"); + win->begin(); + { + new Fl_Input(100, 10, 200, 25, "Input:"); + G_checkbut = new Fl_Check_Button(100,40,280,25," Force numeric keypad to type numbers"); + G_checkbut->labelsize(12); + G_checkbut->set(); + } + win->end(); + win->resizable(win); + win->show(argc, argv); + win->tooltip("Turn NumLock OFF, then type into Input:\nusing numeric keypadt to test translation"); + // Set up our event handler to manage events + Fl::event_dispatch(MyHandler); + return(Fl::run()); +} |