How can I create new window in GTK after click?

Question

I'm new at GTK, and I was wondering how can I create a new window after a click button. I've got this function

void cb_create_entry(GtkWidget *, gpointer);

int create_window(int argc, char *argv[]){
GtkWidget *p_window = NULL;
GtkWidget *p_main_box = NULL;

GtkWidget *p_button[5];

gtk_init (&argc, &argv);

//Create window
p_window = gtk_window_new(GTK_WINDOW_TOPLEVEL);

gtk_window_set_title(GTK_WINDOW(p_window), "Hello");
gtk_window_set_default_size(GTK_WINDOW(p_window), 320, 200);

p_main_box = gtk_vbox_new(TRUE, 0);
gtk_container_add(GTK_CONTAINER(p_window), p_main_box);

{
  p_button[0] = gtk_button_new_with_label("Create entry");
  g_signal_connect(G_OBJECT(p_button[0]), "clicked", 
  G_CALLBACK(cb_create_entry), NULL);
  gtk_box_pack_start(GTK_BOX(p_main_box), p_button[0], FALSE, FALSE, 0);
}
  gtk_widget_show_all(p_window);

  gtk_main ();

  return EXIT_SUCCESS;

and callback.h

#ifndef CALLBACK_H_INCLUDED
#define CALLBACK_H_INCLUDED
#include <gtk/gtk.h>

void cb_create_entry(GtkWidget *p_widget, gpointer user_data){
gtk_button_released(p_widget);
GtkWidget *p_window;
GtkWidget *p_v_box;
GtkWidget *p_entry;

p_window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
gtk_window_set_title(GTK_WINDOW(p_window), "Create DB");
gtk_window_set_default_size(GTK_WINDOW(p_window), 320, 200);

p_v_box = gtk_vbox_new(TRUE, 0);
gtk_container_add(GTK_CONTAINER(p_window), p_v_box);

p_entry = gtk_entry_new();
gtk_box_pack_start(GTK_BOX(p_v_box), p_entry, TRUE, FALSE, 0);
}

and main

int main(int argc, char const *argv[]) {
create_window(argc, argv);
return 0;
}

But it doesn't work. I'd like to create a new window with an input. But when I click on button, nothing happens.

Answer 1

I'm a bit confused on how you laid out your file structure. Since there's no input on that I'll assume that the file with create_window function is the same where you have main. Then, callback.h should not have implementation code.

Nevertheless, i don't see any gtk_widget_show or gtk_widget_show_all calls and not sure you suppressed or just missed them. I'll assume the later because by your description it seems that you can see the initial window.

It's also missing a call to gtk_main.

Adding GtkWidget show functions and gtk_main to your code, it does work like expected:

Lets call the first file main.c :

#include <gtk/gtk.h>
#include "callback.h"

void cb_create_entry(GtkWidget *, gpointer);

int create_window(int argc, char *argv[]){
   GtkWidget *p_window = NULL;
   GtkWidget *p_main_box = NULL;

   GtkWidget *p_button[5];

   gtk_init (&argc, &argv);

   //Create window
   p_window = gtk_window_new(GTK_WINDOW_TOPLEVEL);

   gtk_window_set_title(GTK_WINDOW(p_window), "Hello");
   gtk_window_set_default_size(GTK_WINDOW(p_window), 320, 200);

   p_main_box = gtk_vbox_new(TRUE, 0);
   gtk_container_add(GTK_CONTAINER(p_window), p_main_box);

   p_button[0] = gtk_button_new_with_label("Create entry");
   g_signal_connect(G_OBJECT(p_button[0]), "clicked", 
   G_CALLBACK(cb_create_entry), NULL);
   gtk_box_pack_start(GTK_BOX(p_main_box), p_button[0], FALSE, FALSE, 0);

   gtk_widget_show_all(p_window);
}

int main (int argc, char *argv[]) {
   create_window(argc, argv);
   gtk_main ();
   return 0;
}

And the other file callbacks.h :

#include <gtk/gtk.h>

void cb_create_entry(GtkWidget *p_widget, gpointer user_data){
    gtk_button_released(p_widget);
    GtkWidget *p_window;
    GtkWidget *p_v_box;
    GtkWidget *p_entry;

    p_window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
    gtk_window_set_title(GTK_WINDOW(p_window), "Create DB");
    gtk_window_set_default_size(GTK_WINDOW(p_window), 320, 200);

    p_v_box = gtk_vbox_new(TRUE, 0);
    gtk_container_add(GTK_CONTAINER(p_window), p_v_box);

    p_entry = gtk_entry_new();
    gtk_box_pack_start(GTK_BOX(p_v_box), p_entry, TRUE, FALSE, 0);
    gtk_widget_show_all(p_window);
}

Then compiling with:

gcc -o test main.c callback.h `pkg-config --cflags --libs gtk+-3.0` 

will result in a window with a button, which after being pressed will create and show a new window with a GtkEntry:

Answer 2

now callback.h looks like that :

int cb_create_entry(GtkWidget *p_widget, gpointer user_data){
  GtkWidget *p_window = NULL;
  GtkWidget *p_entry = NULL;
  GtkWidget *p_button = NULL;
  GtkWidget *p_main_box = NULL;
  GtkWidget *p_label = NULL;

  p_window = gtk_window_new(GTK_WINDOW_TOPLEVEL);

  gtk_window_set_title(GTK_WINDOW(p_window), "Create entry");
  gtk_window_set_default_size(GTK_WINDOW(p_window), 320, 200);
  g_signal_connect (G_OBJECT (p_window), "destroy", G_CALLBACK (cb_quit), NULL);

  p_main_box = gtk_vbox_new(TRUE, 0);
  gtk_container_add(GTK_CONTAINER(p_window), p_main_box);

  p_label = gtk_label_new("Please, name your DB");
  gtk_container_add(GTK_CONTAINER(p_main_box), p_label);

  p_entry = gtk_entry_new();
  gtk_container_add(GTK_CONTAINER(p_main_box), p_entry);

  p_button = gtk_button_new_with_label("Create !");
  gtk_container_add(GTK_CONTAINER(p_main_box), p_button);

  {
      GtkWidget *p_quit = NULL;

      p_quit = gtk_button_new_with_label("Quit");
      g_signal_connect(G_OBJECT(p_quit), "clicked", G_CALLBACK(cb_quit), NULL);
      gtk_box_pack_start(GTK_BOX(p_main_box), p_quit, FALSE, FALSE, 0);
  }
  //gtk_widget_show(p_entry);

  gtk_widget_show_all(p_window);

  return EXIT_SUCCESS;}