tests/barf.c

   1 /*
   2  * Compile me with:
   3  * gcc -g -O0 -Wall -pthread -o barf barf.c `pkg-config --cflags --libs gtk+-2.0`
   4  */
   5
   6 #include <gtk/gtk.h>
   7
   8 static glong pager_handler = 0;
   9
  10 static gboolean
  11 quit()
  12 {
  13         gtk_main_quit();
  14         return TRUE;
  15 }
  16
  17 static void
  18 barf(GtkButton *button, GtkTextBuffer *buffer)
  19 {
  20         GtkTextIter end;
  21         gtk_text_buffer_get_end_iter(buffer, &end);
  22
  23         gtk_text_buffer_move_mark_by_name(buffer, "pager_position", &end);
  24
  25         gchar *loremipsum;
  26         g_file_get_contents("loremipsum.txt", &loremipsum, NULL, NULL);
  27         gtk_text_buffer_insert(buffer, &end, loremipsum, -1);
  28         g_free(loremipsum);
  29 }
  30
  31 static void
  32 after_insert(GtkTextBuffer *buffer, GtkTextIter *location, gchar *text, gint len, GtkTextView *textview)
  33 {
  34         while(gtk_events_pending())
  35                 gtk_main_iteration();
  36
  37         GdkRectangle pagerpos, endpos, visiblerect;
  38         GtkTextIter pager, end;
  39         gtk_text_buffer_get_end_iter(buffer, &end);
  40         gtk_text_view_get_visible_rect(textview, &visiblerect);
  41
  42         /* Move the pager to the last visible character in the buffer */
  43         gtk_text_view_get_line_at_y(textview, &pager, visiblerect.y, NULL);
  44         if(!gtk_text_iter_ends_line(&pager))
  45                 gtk_text_iter_forward_to_line_end(&pager);
  46         gtk_text_buffer_move_mark_by_name(buffer, "pager_position", &pager);
  47
  48         gtk_text_view_get_iter_location(textview, &pager, &pagerpos);
  49         gtk_text_view_get_iter_location(textview, &end, &endpos);
  50
  51         g_printerr("View height = %d\n", visiblerect.height);
  52         g_printerr("End - Pager = %d\n", endpos.y - pagerpos.y);
  53
  54         /* Wait for a keypress to advance the pager */
  55         if(endpos.y > pagerpos.y)
  56                 g_signal_handler_unblock(textview, pager_handler);
  57 }
  58
  59 static gboolean
  60 pager_wait(GtkTextView *textview, GdkEventKey *event, GtkTextBuffer *buffer)
  61 {
  62         GdkRectangle pagerpos, endpos, visiblerect;
  63         GtkTextIter pager, end;
  64         GtkTextMark *pagermark = gtk_text_buffer_get_mark(buffer, "pager_position");
  65         gtk_text_view_scroll_to_mark(textview, pagermark, 0.0, TRUE, 0.0, 0.0);
  66
  67         while(gtk_events_pending())
  68                 gtk_main_iteration();
  69
  70         /* Move the pager to the last visible character in the buffer */
  71         gtk_text_view_get_line_at_y(textview, &pager, visiblerect.y, NULL);
  72         if(!gtk_text_iter_ends_line(&pager))
  73                 gtk_text_iter_forward_to_line_end(&pager);
  74         gtk_text_buffer_move_mark(buffer, pagermark, &pager);
  75
  76         gtk_text_buffer_get_end_iter(buffer, &end);
  77         gtk_text_view_get_visible_rect(textview, &visiblerect);
  78         gtk_text_view_get_iter_location(textview, &pager, &pagerpos);
  79         gtk_text_view_get_iter_location(textview, &end, &endpos);
  80
  81         g_printerr("View height = %d\n", visiblerect.height);
  82         g_printerr("End - Pager = %d\n", endpos.y - pagerpos.y);
  83
  84         if(endpos.y == pagerpos.y)
  85                 g_signal_handler_block(textview, pager_handler);
  86
  87         return TRUE; /* block further handlers */
  88 }
  89
  90 int
  91 main(int argc, char **argv)
  92 {
  93         gtk_init(&argc, &argv);
  94
  95         GtkWidget *window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
  96         gtk_widget_set_size_request(window, 400, 400);
  97         GtkWidget *button = gtk_button_new_with_label("Barf");
  98         GtkWidget *scrolledwindow = gtk_scrolled_window_new(NULL, NULL);
  99         GtkWidget *textview = gtk_text_view_new();
 100         gtk_text_view_set_wrap_mode(GTK_TEXT_VIEW(textview), GTK_WRAP_WORD_CHAR);
 101         gtk_text_view_set_editable(GTK_TEXT_VIEW(textview), FALSE);
 102         GtkWidget *vbox = gtk_vbox_new(FALSE, 6);
 103
 104         gtk_container_add(GTK_CONTAINER(scrolledwindow), textview);
 105         gtk_box_pack_start(GTK_BOX(vbox), button, FALSE, FALSE, 0);
 106         gtk_box_pack_start(GTK_BOX(vbox), scrolledwindow, TRUE, TRUE, 0);
 107         gtk_container_add(GTK_CONTAINER(window), vbox);
 108         gtk_widget_show_all(window);
 109
 110         GtkTextBuffer *buffer = gtk_text_view_get_buffer(GTK_TEXT_VIEW(textview));
 111         g_signal_connect_after(buffer, "insert-text", G_CALLBACK(after_insert), textview);
 112         pager_handler = g_signal_connect(textview, "key-press-event", G_CALLBACK(pager_wait), buffer);
 113         g_signal_handler_block(textview, pager_handler);
 114
 115         GtkTextIter end;
 116         gtk_text_buffer_get_end_iter(buffer, &end);
 117         GtkTextMark *pagermark = gtk_text_buffer_create_mark(buffer, "pager_position", &end, TRUE);
 118         gtk_text_mark_set_visible(pagermark, TRUE);
 119
 120         g_signal_connect(window, "delete-event", G_CALLBACK(quit), NULL);
 121         g_signal_connect(button, "clicked", G_CALLBACK(barf), buffer);
 122
 123         gtk_main();
 124         return 0;
 125 }