I'm encountering a Segmentation Fault when I try to make a Gtkwidget point to a memory address where I've load a png from file. I want card[6].image to display the image I've loaded in card[0].image and the I'd like to remove the same image from card[0].image.
struct my_image {
const char *path;
GtkWidget *image;
};
void create_window() {
GtkWidget *window;
GtkWidget *headbar;
GtkWidget *vbox;
GtkWidget *hbox_3;
GtkWidget *hbox_table;
GtkWidget *hbox_1;
GtkWidget *hbox_2;
GtkWidget *about_button;
GtkWidget *event_box1, *event_box2, *event_box3;
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
headbar = gtk_header_bar_new();
about_button = gtk_button_new_with_mnemonic("CLick");
event_box1 = gtk_event_box_new ();
event_box2 = gtk_event_box_new ();
event_box3 = gtk_event_box_new ();
vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 50);
hbox_3 = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 35);
hbox_table = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 35);
hbox_2= gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 0);
hbox_1 = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 35);
gtk_header_bar_set_title (GTK_HEADER_BAR (headbar), "Myprogram");
gtk_window_set_title (GTK_WINDOW (window), "Myprogram");
gtk_window_set_titlebar (GTK_WINDOW (window), headbar);
gtk_header_bar_set_show_close_button (GTK_HEADER_BAR (headbar), TRUE);
gtk_window_maximize (GTK_WINDOW (window));
card[0].path = pile[0];
card[1].path = pile[1];
card[2].path = pile[2];
card[0].image = gtk_image_new_from_file (card[0].path);
card[1].image = gtk_image_new_from_file (card[1].path);
card[2].image = gtk_image_new_from_file (card[2].path);
card[3].path = "c/fort.png";
card[4].path = "c/fort.png";
card[5].path = "c/fort.png";
card[3].image = gtk_image_new_from_file (card[3].path);
card[4].image = gtk_image_new_from_file (card[4].path);
card[5].image = gtk_image_new_from_file (card[5].path);
card[6].image = gtk_image_new ();
card[7].image = gtk_image_new ();
printf("card 0 address = %u\n", card[0].image);
printf("card 6 address = %u\n", card[6].image);
card[8].path = pile[39];
card[9].path = "c/mazzo.png";
card[8].image = gtk_image_new_from_file (card[8].path);
card[9].image = gtk_image_new_from_file (card[9].path);
g_signal_connect (about_button, "clicked", G_CALLfort (activate_about), NULL);
g_signal_connect (G_OBJECT (event_box1), "button_press_event", G_CALLfort (card1_clicked), card);
g_signal_connect (G_OBJECT (event_box2), "button_press_event", G_CALLfort (card2_clicked), card);
g_signal_connect (G_OBJECT (event_box3), "button_press_event", G_CALLfort (card3_clicked), card);
g_signal_connect (G_OBJECT (window), "destroy", G_CALLfort (destroy), NULL);
gtk_container_add(GTK_CONTAINER (headbar), about_button);
gtk_container_add(GTK_CONTAINER (window), vbox);
gtk_container_add(GTK_CONTAINER (vbox), hbox_3);
gtk_container_add(GTK_CONTAINER (vbox), hbox_table);
gtk_container_add(GTK_CONTAINER (vbox), hbox_2);
gtk_container_add(GTK_CONTAINER (vbox), hbox_1);
gtk_container_add(GTK_CONTAINER (hbox_2), card[8].image);
gtk_container_add(GTK_CONTAINER (hbox_2), card[9].image);
gtk_container_add(GTK_CONTAINER (hbox_1), event_box1);
gtk_container_add(GTK_CONTAINER (hbox_1), event_box2);
gtk_container_add(GTK_CONTAINER (hbox_1), event_box3);
gtk_container_add(GTK_CONTAINER (event_box1), card[0].image);
gtk_container_add(GTK_CONTAINER (event_box2), card[1].image);
gtk_container_add(GTK_CONTAINER (event_box3), card[2].image);
gtk_container_add(GTK_CONTAINER (hbox_3), card[3].image);
gtk_container_add(GTK_CONTAINER (hbox_3), card[4].image);
gtk_container_add(GTK_CONTAINER (hbox_3), card[5].image);
gtk_container_add(GTK_CONTAINER (hbox_table), card[6].image);
gtk_container_add(GTK_CONTAINER (hbox_table), card[7].image);
gtk_widget_show_all (window);
gtk_main();
}
void card1_clicked (GtkWidget *window, struct my_image *card)
{
printf("%s\n", card[0].path);
card[6].image = card[0].image;
/*gtk_image_set_from_file(GTK_IMAGE(card[6].image), card[0].path);*/
}
the images initially are displayed correclty but when trigger card1_clciked this line card[6].image = card[0].image; produces a Segmentation Fault.
I'm not sure if I'm loading the image correctly and how to load another image using the same widget; I've also tried to use the function /*gtk_image_set_from_file(GTK_IMAGE(card[6].image), card[0].path);* with the same effect.
Your callback function for button_press_event signal is not defined properly.
The manual tells us how it shall look like:
// The “button-press-event” signal
gboolean
user_function (GtkWidget *widget,
GdkEvent *event,
gpointer user_data)
In your function you are missing one parameter:
void card1_clicked (GtkWidget *window, struct my_image *card)
This means you are using the event pointer to read your card array which causes some illegal read access.
Besides that you do not provide the required boolean return value.