Map Button and function key to each other (e.g. F1 <-> Help)

emax · **Joined:** Sat Dec 31, 2011 2:31 pm **Posts:** 4

Hi all,

can anybody point me to a documentation or give an answer to the following problem:

- my application provides help for most of the widgets on a window. Help shal be provided by pressing the 'F1' function key.
- on the bottom of the window I provide a number of standard buttons, such as OK, Cancel and so on. A 'Help' button shall be provided as well.

For the button, I just use (it's all in perl)

Code:

$button->signal_connect('clicked' => $helpFunc, $dtaPtr)

which works fine.

My questions:
1. How can I achieve that pressing 'F1' triggers the same behaviour (namely a popup window with some help text) ?
2. If 'F1' was used instead of the 'Help' button: How can I optically 'simulate' that a 'Help' button was clicked? (accelerator ..?)

What I would like to have is a guideline, in C, C++ or perl, any of these is allright. To find out the particular equivalent perl calls is not a big issue (I hope :-o).

Your help is very much appreciated.

Greetings,
emax

asdfgh2091 · **Joined:** Fri Sep 04, 2009 6:53 am **Posts:** 61

Your are looking for GtkAccelGroup:

In C (gtk+-2.0):

Code:

#include <gtk/gtk.h>
#include <gdk/gdkkeysyms.h>

void on_help(GtkWidget *widget, gpointer data)
{
    g_print("Help!\n");
}

int main(int argc, char **argv)
{
    gtk_init(&argc,&argv);
    GtkWidget *window=gtk_window_new(GTK_WINDOW_TOPLEVEL);
    g_signal_connect(G_OBJECT(window),"destroy",G_CALLBACK(gtk_main_quit),NULL);

    GtkWidget *button=gtk_button_new_with_label("Help");
    gtk_container_add(GTK_CONTAINER(window),button);
    g_signal_connect(G_OBJECT(button),"clicked",G_CALLBACK(on_help),NULL);

    GtkAccelGroup *accel_group=gtk_accel_group_new();
    gtk_window_add_accel_group(GTK_WINDOW(window),accel_group);
    gtk_widget_add_accelerator(button,"clicked",accel_group,GDK_KEY_F1,0,0);

    gtk_widget_show_all(window);
    gtk_main();
    return 0;
}

emax · **Joined:** Sat Dec 31, 2011 2:31 pm **Posts:** 4

I will try this in perl.

Thanks a lot! :-)

emax · **Joined:** Sat Dec 31, 2011 2:31 pm **Posts:** 4

The example worked fine in C, execpt for the GDK_KEY_F1 which is a GDK_F1 in my installation.

Thank you again.

But with the perl-bindings, the "gtk_widget_add_accelerator(button,"clicked",accel_group,GDK_KEY_F1,0,0);" equivalent doesn't accept zeros for the mask and the modifier parameter. I have to provide a value, which is a problem as I do not want to use a modifier (such as CTRL).

I think, I will go with key_press_event and check for such keypresses 'manually'.

emax · **Joined:** Sat Dec 31, 2011 2:31 pm **Posts:** 4

Update:

In perl, things differ a little bit, and I finally could add an accelerator. The 'zero' values are done differently as well, so to whom it may concern - here is the result:

Code:

    # f1:Help button
    my $button = Gtk2::Button->new('F1: Help');
    $button->signal_connect('clicked' => \&dummyHelp);
    my $accelGroup = Gtk2::AccelGroup->new;
    $accelGroup->connect($Gtk2::Gdk::Keysyms{F1}, [], [], \&dummyHelp);
    $window->add_accel_group($accelGroup);

So there is no add_accelerator, instead, a connect call has to be done.

GTK+ Forums

Map Button and function key to each other (e.g. F1 <-> Help)

Who is online