Re: [fltk.general] Re: Losing keyboard input under user 'spamming' input - Forums

On Friday, September 24, 2021 at 6:24:28 PM UTC+10 Ian MacArthur wrote:

On Friday, 24 September 2021 at 08:57:20 UTC+1 Ian MacArthur wrote:

Interestingly, I actually looked at the docs for Keyboard Events, and it includes this exhortation:

Todo: Add details on how to detect repeating keys, since on some X servers a repeating key will generate both FL_KEYUP and FL_KEYDOWN, such that to tell if a key is held, you need Fl::event_key(int) to detect if the key is being held down during FL_KEYUP or not.

I don't know who wrote that (I'm fairly sure it was not me, at any rate!) but that sounds like exactly the thing... Might be worth a try.

And for (even more!) completeness, here's what I think that might mean - though given that I'm not on X11 today I have no clue of this will work or not.
Works. OK on Win10, but that's not all that helpful in this instance...

////////////////////////////
#include <FL/Fl.H>
#include <FL/Fl_Double_Window.H>
#include <FL/Fl_Menu_Bar.H>

static int shown_v = 0;

class my_win : public Fl_Double_Window {

int handle (int);

int please_change;
public:
my_win(int x, int y,int w,int h,const char* L):Fl_Double_Window(x,y,w,h,L), please_change(0) {};
}; // my_win

int my_win::handle (int e) {
int ret = Fl_Double_Window::handle(e);
if (e == FL_KEYDOWN) {
if (Fl::event_state() & FL_ALT) {
if (Fl::event_key() == 's') {
please_change = (-1);
return 1;
}
}
}
else if (e == FL_KEYUP) {
if (please_change) {
if ((Fl::event_state() & FL_ALT) && (Fl::event_key() == 's')) {
// Probably a synthetic repeat keyup on X11? Ignore...
return 1;
}
else { // Assumed to be a real keyup
please_change = 0;
if (shown_v) {
this->hide();
shown_v = 0;
}
else {
this->show();
shown_v = 1;
}
return 1;
}
}
}
return ret;
} // my_win::handle

static void toggle_win (Fl_Widget*,void* data) {
my_win* w = static_cast<my_win*>(data);

if (shown_v) {
w->hide();
shown_v = 0;
}
else {
w->show();
shown_v = 1;
}
} // toggle_win

int main() {
shown_v = 0;

my_win *win2 = new my_win(0.5*Fl::w()-100,0.5*Fl::h()-100,200,200,"2nd Win");
win2->end();

Fl_Double_Window *win = new Fl_Double_Window(0.5*Fl::w()-200,0.5*Fl::h()-200,400,400,"Main Win");
win->begin();
win->box (FL_FLAT_BOX);

Fl_Menu_Item items[] = {
{"Menu1",0,0,0,FL_SUBMENU,0,0,FL_NORMAL_SIZE,FL_BLACK}, //0
{"Hide/show second window",FL_ALT+'s',toggle_win,win2,0,0,0,FL_NORMAL_SIZE,FL_BLACK},
{0,0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0,0}
};

Fl_Menu_Bar *menu = new Fl_Menu_Bar(0, 0, win->w(),25);
menu->box (FL_BORDER_BOX);
menu->menu(items);
win->end();
win->show();

return Fl::run();
} // main
// end of file