gtk2/demos/gtk-demo/textundo.c
2020-02-14 21:18:49 +01:00

72 lines
2.2 KiB
C

/* Text View/Undo and Redo
*
* The GtkTextView supports undo and redo through the use of a
* GtkTextBuffer. You can enable or disable undo support using
* gtk_text_buffer_set_enable_undo().
*
* Use Primary+Z to undo and Primary+Shift+Z or Primary+Y to
* redo previously undone operations.
*/
#include <gtk/gtk.h>
#include <stdlib.h> /* for exit() */
GtkWidget *
do_textundo (GtkWidget *do_widget)
{
static GtkWidget *window = NULL;
if (!window)
{
GtkWidget *view;
GtkWidget *sw;
GtkTextBuffer *buffer;
GtkTextIter iter;
window = gtk_window_new ();
gtk_window_set_display (GTK_WINDOW (window),
gtk_widget_get_display (do_widget));
gtk_window_set_default_size (GTK_WINDOW (window),
450, 450);
g_signal_connect (window, "destroy",
G_CALLBACK (gtk_widget_destroyed), &window);
gtk_window_set_title (GTK_WINDOW (window), "TextView Undo");
view = gtk_text_view_new ();
gtk_text_view_set_wrap_mode (GTK_TEXT_VIEW (view), GTK_WRAP_WORD);
buffer = gtk_text_view_get_buffer (GTK_TEXT_VIEW (view));
gtk_text_buffer_set_enable_undo (buffer, TRUE);
/* this text cannot be undone */
gtk_text_buffer_begin_irreversible_action (buffer);
gtk_text_buffer_get_start_iter (buffer, &iter);
gtk_text_buffer_insert (buffer, &iter,
"Type to add more text.\n"
"Use Primary+Z to undo and Primary+Shift+Z to redo a previously undone action.\n"
"\n",
-1);
gtk_text_buffer_end_irreversible_action (buffer);
sw = gtk_scrolled_window_new (NULL, NULL);
gtk_scrolled_window_set_policy (GTK_SCROLLED_WINDOW (sw),
GTK_POLICY_AUTOMATIC,
GTK_POLICY_AUTOMATIC);
gtk_container_add (GTK_CONTAINER (window), sw);
gtk_container_add (GTK_CONTAINER (sw), view);
}
if (!gtk_widget_get_visible (window))
{
gtk_widget_show (window);
}
else
{
gtk_widget_destroy (window);
window = NULL;
}
return window;
}