Improve handling of events in test/handle_keys.cxx

(1) Ensure that the terminal widgets doesn't use keyboard events.
  Advantage: keyboard navigation and selection doesn't interfere
    with the display.
  Drawback: Contents of the terminal can no longer be copied.
    This will be addressed in a later update.

(2) Thanks to Manolo for his addition of the "GUI scaling" button.
  Although GUI scaling can be useful, it can also be annoying while
  testing shortcuts.

(3) Changed all light buttons to check buttons.

1 files changed, 42 insertions, 13 deletions

diff --git a/test/handle_keys.cxx b/test/handle_keys.cxx
index 97464773e..09838a5de 100644
--- a/test/handle_keys.cxx
+++ b/test/handle_keys.cxx
@@ -20,15 +20,16 @@
 #include <FL/Fl_Terminal.H>
 #include <FL/Fl_Grid.H>
 #include <FL/Fl_Button.H>
-#include <FL/Fl_Light_Button.H>
+#include <FL/Fl_Check_Button.H>
 #include <FL/names.h>
 #include <stdio.h>
 
 // Global variables to simplify the code
 
-Fl_Light_Button *keydown  = NULL;
-Fl_Light_Button *keyup    = NULL;
-Fl_Light_Button *shortcut = NULL;
+Fl_Check_Button *keydown  = NULL;
+Fl_Check_Button *keyup    = NULL;
+Fl_Check_Button *shortcut = NULL;
+Fl_Check_Button *scaling  = NULL;
 
 // Text in the headline and after clearing the terminal buffer. For alignment ...
 //          1         2         3         4         5         6         7         8
@@ -135,6 +136,21 @@ const char *get_keyname(int k, int &lg) {
   return buffer;
 }
 
+class Terminal : public Fl_Terminal {
+public:
+  int handle(int ev) FL_OVERRIDE {
+    switch(ev) {
+    case FL_KEYBOARD:
+    case FL_KEYUP:
+    case FL_SHORTCUT:
+      return 0;
+    }
+  return Fl_Terminal::handle(ev);
+  }
+  Terminal(int X, int Y, int W, int H)
+  : Fl_Terminal(X, Y, W, H) {}
+};
+
 // Class to handle events
 class app : public Fl_Double_Window {
 protected:
@@ -143,7 +159,7 @@ public:
   // storage for the last event
   int eventnum;
   const char *eventname;
-  Fl_Terminal *tty;
+  Terminal *tty;
   Fl_Box *headline;
   app(int X, int Y, int W, int H, const char *L = 0)
     : Fl_Double_Window(X, Y, W, H, L) {
@@ -157,7 +173,7 @@ public:
     headline->labelsize(12);
     headline->label(headline_text);
     headline->tooltip(tt);
-    tty = new Fl_Terminal(0, 25, W, H - 125);
+    tty = new Terminal(0, 25, W, H - 100);
     tty->color(FL_WHITE);
     tty->textfgcolor(fl_darker(FL_BLUE));
     tty->selectionbgcolor(FL_BLUE);
@@ -245,9 +261,9 @@ void quit_cb(Fl_Widget *w, void *) {
   w->window()->hide();
 }
 
-// Clear button callback: clears the terminal display
+// Clear button callback: clears the terminal widget
 void clear_cb(Fl_Button *b, void *) {
-  Fl_Terminal *tty = ((app *)b->window())->tty;
+  Terminal *tty = ((app *)b->window())->tty;
   tty->clear_screen_home();
   tty->clear_history();
   tty->printf("%s\n", headline_text); // test, helpful for copy to clipboard
@@ -257,10 +273,17 @@ void clear_cb(Fl_Button *b, void *) {
 
 // Callback for all (light) buttons
 void toggle_cb(Fl_Widget *w, void *) {
-  Fl_Terminal *tty = ((app *)w->window())->tty;
+  Terminal *tty = ((app *)w->window())->tty;
   tty->take_focus();
 }
 
+// Toggle recognition of GUI scaling shortcuts
+void toggle_scaling(Fl_Widget *w, void *v) {
+  int toggle = ((Fl_Button*)w)->value() ? 1 : 0;
+  Fl::keyboard_screen_scaling(toggle);
+  toggle_cb(w, v); // give focus to 'app'
+}
+
 // Window close callback (Esc does not close the window)
 void close_cb(Fl_Widget *win, void *) {
   if (Fl::event() == FL_SHORTCUT)
@@ -288,22 +311,28 @@ int main(int argc, char **argv) {
   win->tty->box(FL_DOWN_BOX);
   win->tty->printf("Please press any key ...\n");
 
-  Fl_Grid *grid = new Fl_Grid(0, WH - 100, WW, 100);
+  Fl_Grid *grid = new Fl_Grid(0, WH - 75, WW, 75);
   grid->layout(2, 5, 5, 5);
 
-  keydown = new Fl_Light_Button(0, 0, 80, 30, "Keydown");
+  keydown = new Fl_Check_Button(0, 0, 80, 30, "Keydown");
   grid->widget(keydown, 0, 1);
   keydown->value(1);
   keydown->callback(toggle_cb);
   keydown->tooltip("Show FL_KEYDOWN aka FL_KEYBOARD events");
 
-  keyup = new Fl_Light_Button(0, 0, 80, 30, "Keyup");
+  keyup = new Fl_Check_Button(0, 0, 80, 30, "Keyup");
   grid->widget(keyup, 0, 2);
   keyup->value(0);
   keyup->callback(toggle_cb);
   keyup->tooltip("Show FL_KEYUP events");
 
-  shortcut = new Fl_Light_Button(0, 0, 80, 30, "Shortcut");
+  scaling = new Fl_Check_Button(0, 0, 80, 30, "GUI scaling");
+  grid->widget(scaling, 1, 2);
+  scaling->value(1);
+  scaling->callback(toggle_scaling);
+  scaling->tooltip("Use GUI scaling shortcuts");
+
+  shortcut = new Fl_Check_Button(0, 0, 80, 30, "Shortcut");
   grid->widget(shortcut, 0, 3);
   shortcut->value(0);
   shortcut->callback(toggle_cb);