GTK+ Forums

macrod · Joined: 26 Feb 2008 Posts: 1

Was wondering if anybody has any idea(s) why the code below would seem to work fine on GTK/X11 (at least I don't see any error messages), but fail on GTK/DirectFB? When the application is exited by hitting the "Quit" button, I receive the following error message:

*** glibc detected *** TextDemo: double free or corruption (out): 0x4035b1b0 ***

I'm trying to figure out if this is a GTK related problem (i.e., am I'm doing something wrong in GTK) or a problem with GTK/DirectFB. I have to assume that my code IS the problem, but I just don't see where / how.

The reason for doing the sample code this way is that I noticed this problem in my application which destroys the parent view which contains a text view and then re-uses the space for other widgets. The interesting thing is that if I disable the text view creation and only leave the 'Quit' button, the application exits just fine without any messages. I see the same behavior with my "real" application in that I can switch between different forms without any problems unless it contains a text view widget.

What am I doing wrong here?

Code: (Plaintext)

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#include "common.h"

GtkWidget* main_window;

static gboolean destroy_event(GtkWidget* widget, void* data)
{
gtk_main_quit();
return FALSE;
}

static void button_click_event(void)
{
gtk_widget_destroy(main_window);
}

int main(int argc, char* argv[])
{
GtkWidget *text_view, *box, *button;

// initialize multi-threading within GLib
g_thread_init(NULL);

// initialize multi-threading within GDK
gdk_threads_init();

// acquire thread lock
gdk_threads_enter();
gtk_init(&argc, &argv);

// create main window
main_window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
if (main_window == NULL)
abort();
g_signal_connect(G_OBJECT(main_window), "destroy", G_CALLBACK(destroy_event), NULL);
gtk_widget_show(main_window);

box = gtk_vbox_new(FALSE, 5);
if (box == NULL)
abort();
gtk_widget_show(box);
gtk_container_add(GTK_CONTAINER(main_window), box);

text_view = gtk_text_view_new();
if (text_view == NULL)
abort();
gtk_widget_show(text_view);
gtk_box_pack_start(GTK_BOX(box), text_view, TRUE, TRUE, 5);

button = gtk_button_new_with_label("Quit");
if (button == NULL)
abort();
g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(button_click_event), NULL);
gtk_widget_show(button);
gtk_box_pack_start(GTK_BOX(box), button, TRUE, TRUE, 5);

// run the main loop
gtk_main();

// release thread lock
gdk_threads_leave();

return 0;
}