Re: setting initial state of radio buttons not working

[Olexiy Avramchenko <ath beast stu cn ua>]

Hello, Brandon
As I see you have only one problem: if you're creating a new group of
radio buttons you have to pass NULL pointer as group. Then you have
to obtain the groups pointer via gtk_radio_button_group(). You may also
use gtk_radio_button_new_with_label_from_widget() function to create
the next button in group without specifying the group.

Brandon McCombs wrote:

> globally declared I have the following:
>
> GtkWidget *radio_straightplay;
> GtkWidget *radio_boxplay;
>
> then in main() I have:
>
> radio_straightplay =
> gtk_radio_button_new_with_label(radiogroup,"Straight");
Nope, an error here. You have to pass NULL GSlist pointer - a new group 
will be created.

radio_straightplay = gtk_radio_button_new_with_label(NULL,"Straight");

Then you have to obtain the pointer to group via gtk_radio_button_group() :

radiogroup = gtk_radio_button_group((GtkRadioButton*)radio_straightplay);

> radio_boxplay = gtk_radio_button_new_with_label(radiogroup,"Box");
This call is correct now.

> radiogroup = gtk_radio_button_group(GTK_RADIO_BUTTON(radio_boxplay));
> radiogroup =
> gtk_radio_button_group(GTK_RADIO_BUTTON(radio_straightplay));
You have to remove this lines, cause you're already have a pointer to group.

> Now, i don't get any errors or warnings with these and they are
> displayed but both radio buttons are checked. Is that normal default
> behavior in the first place? 
Yes, cause you've created two buttons in two different groups.

> To turn that off I tried the following:
> gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(radio_straightplay),TRUE);
> gtk_toggle_button_set_active((radio_boxplay),FALSE);
This will work ok in all cases. Typecasting needed only for avoiding 
compiler
warnings and checking the type of the object in run-time. You may use 
usual C
typecasting (GtkToggleButton*)radio_button in case you are sure about 
the type
of radio_button pointer (this can save a  couple of microseconds :).

Hope this help. Look at little demo (gtk+-1.2) I've attached.

Regards,
   Olexiy

/*
        To compile use smth like this:
        
        gcc -O -Wall `gtk-config --cflags --libs` radio-test.c -o radio-test

        Olexiy Avramchenko
*/

#include <gtk/gtk.h>


static void set_active(GtkWidget *button, GtkToggleButton *radio)
{
        gtk_toggle_button_set_active(radio, TRUE);
}

int main(int argc, char **argv)
{
GSList    *group;
GtkWidget *window;
GtkWidget *vbox;
GtkWidget *radio0, *radio1, *radio2;
GtkWidget *sep;
GtkWidget *button;

        gtk_init(&argc, &argv);

        window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
        gtk_container_set_border_width(GTK_CONTAINER(window), 8);
        gtk_signal_connect(
                                GTK_OBJECT(window),
                                "delete_event",
                                gtk_main_quit,
                                NULL
        );

        vbox = gtk_vbox_new(FALSE, 2);
        gtk_container_add(GTK_CONTAINER(window), vbox);

        /*      creating the first radio button in group, passing
                NULL as group.
        */
        radio0 = gtk_radio_button_new_with_label(NULL, "radio button 0");
        gtk_box_pack_start(GTK_BOX(vbox), radio0, FALSE,FALSE, 0);
        /*      getting the pointer to new group
        */
        group = gtk_radio_button_group(GTK_RADIO_BUTTON(radio0));

        /*      creating new radio button in group, passing group pointer
        */
        radio1 = gtk_radio_button_new_with_label(group, "radio button 1");
        gtk_box_pack_start(GTK_BOX(vbox), radio1, FALSE,FALSE, 0);

        /*      creating new radio button in group in another way
        */
        radio2 = gtk_radio_button_new_with_label_from_widget(GTK_RADIO_BUTTON(radio1), "radio button 2");
        gtk_box_pack_start(GTK_BOX(vbox), radio2, FALSE,FALSE, 0);

        sep = gtk_hseparator_new();
        gtk_box_pack_start(GTK_BOX(vbox), sep, FALSE,FALSE, 4);

        /*      three buttons for manually radio buttons activation
        */
        button = gtk_button_new_with_label("set *radio button 0* active");
        gtk_signal_connect(
                                GTK_OBJECT(button),
                                "clicked",
                                set_active,
                                radio0
        );
        gtk_box_pack_start(GTK_BOX(vbox), button, FALSE,FALSE, 4);

        button = gtk_button_new_with_label("set *radio button 1* active");
        gtk_signal_connect(
                                GTK_OBJECT(button),
                                "clicked",
                                set_active,
                                radio1
        );
        gtk_box_pack_start(GTK_BOX(vbox), button, FALSE,FALSE, 4);
        button = gtk_button_new_with_label("set *radio button 2* active");
        gtk_signal_connect(
                                GTK_OBJECT(button),
                                "clicked",
                                set_active,
                                radio2
        );
        gtk_box_pack_start(GTK_BOX(vbox), button, FALSE,FALSE, 4);

        gtk_widget_show_all(window);

        gtk_main();

        return 0;
}