GTK+ Forums

Micah Carrick

Somebody asked in gtk-list how to "capture" the Enter key being pressed in a GtkComboBox rather than the default behavior in which the combo box simply "drops down" when the enter key is pressed. I wrote this little ditty to test it out... it uses the GtkWindow "key-press-event" to capture the enter key being pressed and if it IS the enter key, I print the value in the GtkComboBox to the screen.

Code: (Plaintext)

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/*
Compile with:
gcc -Wall -g -o combo_enter `pkg-config --cflags --libs gtk+-2.0` combo_enter.c

Note: gdk/gdkkeysyms is not included in gtk.h. It contains the keycodes we need
to capture the "return" key being pressed.
*/
#include <gtk/gtk.h>
#include <gdk/gdkkeysyms.h>

/* prototypes */
static void destroy (GtkWidget*, gpointer);
gboolean on_combo_key_press (GtkWidget *widget, GdkEventKey *event, gpointer user_data);

int main (int argc, char *argv[])
{
GtkWidget *window = NULL;
GtkWidget *combo = NULL;

gtk_init (&argc, &argv);

/* setup GtkWindow */
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_widget_set_size_request (window, 150, 30);
g_signal_connect (G_OBJECT (window), "destroy",
G_CALLBACK (destroy), NULL);

/* setup a test GtkComboBox */
combo = gtk_combo_box_new_text ();
gtk_combo_box_append_text (GTK_COMBO_BOX(combo), "test 1");
gtk_combo_box_append_text (GTK_COMBO_BOX(combo), "test 2");
g_signal_connect (G_OBJECT (combo), "key-press-event",
G_CALLBACK (on_combo_key_press), NULL);

gtk_container_add (GTK_CONTAINER (window), combo);

/* show window */
gtk_widget_show_all (window);
gtk_main ();

return 0;
}

static void
destroy (GtkWidget *window, gpointer data)
{
gtk_main_quit ();
}

gboolean
on_combo_key_press (GtkWidget *widget, GdkEventKey *event, gpointer user_data)
{
/* user has pressed a key on/in the GtkComboBox */

if (event->keyval == GDK_Return)
{
/* user pressed the enter key */
gchar *str = gtk_combo_box_get_active_text (GTK_COMBO_BOX(widget));
g_print ("Value: %s\n", str);
g_free (str);

return TRUE; /* don't let the box "drop down" */
}
else
{
return FALSE; /* propogate event */
}
}

openldev · Posted: Thu Jan 11, 2007 7:54 pm Post subject:

I'm not sure, but GtkWidget's can-activate-accel or mnemonic-activate signals may be of some help too.

Micah Carrick · Posted: Thu Jan 11, 2007 8:02 pm Post subject:

Good point.

The question in the gtk-list actually wanted to capture the event to "send a message" to the user specified in the combo box in an IM-like application... which could be done where I have it printing the value to the screen.