Reference link:

Code:

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

static int num = 0;



void deal(GtkButton *button, gpointer data)
{
	if(NULL == data)
		return ;
	
	num++;
	
	switch(num)
	{
		case 1://Set button text content
		{
			gtk_button_set_label((GtkButton *) data, "ooooohahahahhahaha");
			break;	
		}
		case 2://Get button text content
		{
			const gchar *text = gtk_button_get_label((GtkButton *)data);
			if(NULL != text)
				printf("text :%s \n", text);	
			break;
		}
		case 3://Set button enable :  Disable the button
		{
			gtk_widget_set_sensitive((GtkWidget *)data, FALSE);
			break;
		}
		case 4://Set button enable :  Enable button
		{
			gtk_widget_set_sensitive((GtkWidget *)data, TRUE);
			break;
		}
		case 5://Set a picture for the button
		{
			GtkWidget *image = gtk_image_new_from_file("1.png");
			gtk_button_set_image(GTK_BUTTON(data), image);	

			break;
		}	
		case 6://Get the picture on the button
		{
			/* No operation*/
			break;
		}
		case 7://Set the transparent background color of the button
		{
			 gtk_button_set_relief((GtkButton *)data, GTK_RELIEF_NONE);	
			
			break;
		}
		case 8://Set the button to normal mode (background is opaque)
		{
			gtk_button_set_relief((GtkButton *)data, GTK_RELIEF_NORMAL);	
			break;
		}
		case 9:////Set the button to be half transparent
		{
			gtk_button_set_relief((GtkButton *)data, GTK_RELIEF_HALF);	
			break;
		}
		case 10://Set the button to normal mode (background is opaque)
		{
			gtk_button_set_relief((GtkButton *)data, GTK_RELIEF_NORMAL);	
			break;
		}	
		default:
		{
			printf("num :%d \n", num);
			break;
		}
	
	}
	if(num >= 10)
	{
		num = 0;
	}	
}




int main(int argc, char **argv)
{
	GtkWidget *window = NULL;
	GtkWidget *button1 = NULL;
	GtkWidget *button2 = NULL;
	GtkWidget *vbox = NULL;


	//Initialize gtk
	gtk_init(&argc, &argv);
	window = gtk_window_new(GTK_WINDOW_TOPLEVEL);

	gtk_widget_set_size_request(window, 200*2, 141*2);
	gtk_window_set_resizable(GTK_WINDOW(window), TRUE);
	gtk_window_set_position(GTK_WINDOW(window), GTK_WIN_POS_CENTER);
	g_signal_connect(window, "destroy", G_CALLBACK(gtk_main_quit), NULL);
	
	vbox = gtk_vbox_new(TRUE, 10);
	gtk_container_add(GTK_CONTAINER(window), vbox);

	button1 = gtk_button_new_with_label("button1");	
	button2 = gtk_button_new_with_label("button2");	

	gtk_container_add(GTK_CONTAINER(vbox), button1);
	gtk_container_add(GTK_CONTAINER(vbox), button2);


	g_signal_connect(button2, "pressed", G_CALLBACK(deal), button1);
	//g_signal_connect(button1, "pressed", G_CALLBACK(deal1), NULL);

	gtk_widget_show_all(window);	
	gtk_main();

	return 0;
}

Compile command:

gcc  demo.c -o demo `pkg-config --cflags --libs gtk+-2.0`

Run screenshot: