Glade 3 and C, signal Handling for button and textbox

Question

I am a beginner at Glade but have experience in C programming.

I am trying to build a project that accepts two values and displays sum.

I have used following:

textbox1 - (entry1) ---- for first value,
textbox2 - (entry2) ---- for 2nd value,
textbox3 - (entry3) ---- to display result,
button - (button1) ---- to calculate sum,
signal - (on_button1_clicked) ---- to handle sum function.

Please help me with the signal code.

#include <gtk/gtk.h>
#include <stdio.h>

    GtkBuilder *builder;
    GtkWidget  *window;
    GError     *error = NULL;

void on_button1_clicked
{

// Need Help in this section

}

void on_window1_destroy (GtkObject *object, gpointer user_data)
{
gtk_main_quit();
}

int main( int argc, char **argv )
{

    /* Init GTK+ */
    gtk_init( &argc, &argv );

    /* Create new GtkBuilder object */
    builder = gtk_builder_new();
    /* Load UI from file. If error occurs, report it and quit application.
     * Replace "tut.glade" with your saved project. */
    if( ! gtk_builder_add_from_file( builder, "sum.glade", &error ) )
    {
        g_warning( "%s", error->message );
        g_free( error );
        return( 1 );
    }

    /* Get main window pointer from UI */
    window = GTK_WIDGET( gtk_builder_get_object( builder, "window1" ) );

    /* Connect signals */
    gtk_builder_connect_signals( builder, NULL );

    /* Destroy builder, since we don't need it anymore */
    g_object_unref( G_OBJECT( builder ) );

    /* Show window. All other widgets are automatically shown by GtkBuilder */
    gtk_widget_show( window );

    /* Start main loop */
    gtk_main();

    return( 0 );
}

Answer 1

I tried the stuff out and with some help could make it work. Here is what you need to refer Click

Answer 2

#include <gtk/gtk.h>
#include<stdio.h>
#include<stdlib.h>
#include <string.h>

/*i have grouped all the widgets in one structure. this technique will 
help if you have huge number of  windows in your project. 
as the number of window will increase the variable we declare will increase
 and the declared variables can have same name of different windows */
struct login_window
{
   GtkEntry *e1;//textbox1
   GtkEntry *e2;//textbox2
   GtkEntry *e3;//textbox3
};
typedef struct login_window widgets;


G_MODULE_EXPORT void on_window1_destroy ()
{
    gtk_main_quit ();
}


G_MODULE_EXPORT void on_button1_clicked ( GtkButton *button,widgets *widg )
{
    char ch1[5],ch2[5],ch[5];
    int a;
//getting text from the text boxes
 const gchar *text1 = gtk_entry_get_text( widg->e2 );
 const gchar *text2 = gtk_entry_get_text( widg->e1 );

 //copying the text of textbox into an array
 strcpy(ch1,text1);
 strcpy(ch2,text2);

 //converting characters to integer and adding them
 a=(atoi(ch1))+(atoi(ch2));

itoa(a,ch,5);//converting integer to character
 gtk_entry_set_text (widg->e3,ch);//setting or displaying text(output) to the third text box
}

int main(int argc, char *argv[])
{
    GtkBuilder *gtkBuilder;
    widgets   widg;
    GtkWidget  *window;

    gtk_init(&argc, &argv);
    gtkBuilder = gtk_builder_new();

    gtk_builder_add_from_file(gtkBuilder, "window.glade", NULL);


    window = GTK_WIDGET( gtk_builder_get_object( gtkBuilder, "window1") );

//connecting each structure member to it appropriate gtkwidget
    widg.e1 = GTK_ENTRY( gtk_builder_get_object( gtkBuilder, "entry1" ) ); 
    widg.e2 = GTK_ENTRY( gtk_builder_get_object( gtkBuilder, "entry2" ) );
    widg.e3 = GTK_ENTRY( gtk_builder_get_object( gtkBuilder, "entry3" ) );

/*connecting signals so that appropriate handlers can be called when button is clicked*/
    gtk_builder_connect_signals( gtkBuilder, &widg );

    g_object_unref(G_OBJECT(gtkBuilder));
    gtk_widget_show(window);//showing the window
    gtk_main();

    return 0;
}

Answer 3

I'll not tell you exactly how to do it, but thinking through your problem logically: you need to

1. Get the text out of entry1 and entry2
2. Convert the strings to integers.
3. Add them together
4. Convert the answer to a string
5. Set the text on entry3

I'm sure you can find some useful functions to do the Gtk+ parts of this in the documentation: GtkEntry documentation