Inserting newlines into a GtkTextView widget (GTK+ programming) - c

Question

I've got a button which when clicked copies and appends the text from a GtkEntry widget into a GtkTextView widget. (This code is a modified version of an example found in the "The Text View Widget" chapter of Foundations of GTK+ Development.)
I'm looking to insert a newline character before the text which gets copied and appended, such that each line of text will be on its own line in the GtkTextView widget. How would I do this? I'm brand new to GTK+.
Here's the code sample:
#include <gtk/gtk.h>
typedef struct
{
GtkWidget *entry, *textview;
} Widgets;
static void insert_text (GtkButton*, Widgets*);
int main (int argc,
char *argv[])
{
GtkWidget *window, *scrolled_win, *hbox, *vbox, *insert;
Widgets *w = g_slice_new (Widgets);
gtk_init (&argc, &argv);
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_window_set_title (GTK_WINDOW (window), "Text Iterators");
gtk_container_set_border_width (GTK_CONTAINER (window), 10);
gtk_widget_set_size_request (window, -1, 200);
w->textview = gtk_text_view_new ();
w->entry = gtk_entry_new ();
insert = gtk_button_new_with_label ("Insert Text");
g_signal_connect (G_OBJECT (insert), "clicked",
G_CALLBACK (insert_text),
(gpointer) w);
scrolled_win = gtk_scrolled_window_new (NULL, NULL);
gtk_container_add (GTK_CONTAINER (scrolled_win), w->textview);
hbox = gtk_hbox_new (FALSE, 5);
gtk_box_pack_start_defaults (GTK_BOX (hbox), w->entry);
gtk_box_pack_start_defaults (GTK_BOX (hbox), insert);
vbox = gtk_vbox_new (FALSE, 5);
gtk_box_pack_start (GTK_BOX (vbox), scrolled_win, TRUE, TRUE, 0);
gtk_box_pack_start (GTK_BOX (vbox), hbox, FALSE, TRUE, 0);
gtk_container_add (GTK_CONTAINER (window), vbox);
gtk_widget_show_all (window);
gtk_main();
return 0;
}
/* Insert the text from the GtkEntry into the GtkTextView. */
static void
insert_text (GtkButton *button,
Widgets *w)
{
GtkTextBuffer *buffer;
GtkTextMark *mark;
GtkTextIter iter;
const gchar *text;
buffer = gtk_text_view_get_buffer (GTK_TEXT_VIEW (w->textview));
text = gtk_entry_get_text (GTK_ENTRY (w->entry));
mark = gtk_text_buffer_get_insert (buffer);
gtk_text_buffer_get_iter_at_mark (buffer, &iter, mark);
gtk_text_buffer_insert (buffer, &iter, text, -1);
}
You can compile this code using the following command (assuming the file is named file.c):
gcc file.c -o file `pkg-config --cflags --libs gtk+-2.0`
Thanks everybody!

Answer 1

Perhaps you could just insert the newline character the same way you insert other characters:
...
mark = gtk_text_buffer_get_insert (buffer);
gtk_text_buffer_get_iter_at_mark (buffer, &iter, mark);
/* Insert newline (only if there's already text in the buffer). */
if (gtk_text_buffer_get_char_count(buffer))
gtk_text_buffer_insert (buffer, &iter, "\n", 1);
gtk_text_buffer_insert (buffer, &iter, text, -1);
...
"\n" is a string containing the newline character in C, and it works just fine in GTK (unless it doesn't in Windows for some weird reason).
Unhelpful blurb: The 1 can just as easily be -1 here; it just tells GTK it only needs to read 1 character, which might be a little faster. Granted, that line of code should almost never be a bottleneck :-)