Pileus Git - ~andy/gtk/blob - demos/gtk-demo/css_pixbufs.c

   1 /* CSS Theming/Animated backgrounds
   2  *
   3  * This demo is done in honour of the Pixbufs demo further down. It is done exclusively
   4  * with CSS as the background of the window.
   5  */
   6
   7 #include <gtk/gtk.h>
   8
   9 static GtkWidget *window = NULL;
  10
  11 static void
  12 show_parsing_error (GtkCssProvider *provider,
  13                     GtkCssSection  *section,
  14                     const GError   *error,
  15                     GtkTextBuffer  *buffer)
  16 {
  17   GtkTextIter start, end;
  18   const char *tag_name;
  19
  20   gtk_text_buffer_get_iter_at_line_index (buffer,
  21                                           &start,
  22                                           gtk_css_section_get_start_line (section),
  23                                           gtk_css_section_get_start_position (section));
  24   gtk_text_buffer_get_iter_at_line_index (buffer,
  25                                           &end,
  26                                           gtk_css_section_get_end_line (section),
  27                                           gtk_css_section_get_end_position (section));
  28
  29   if (g_error_matches (error, GTK_CSS_PROVIDER_ERROR, GTK_CSS_PROVIDER_ERROR_DEPRECATED))
  30     tag_name = "warning";
  31   else
  32     tag_name = "error";
  33
  34   gtk_text_buffer_apply_tag_by_name (buffer, tag_name, &start, &end);
  35 }
  36
  37 static void
  38 css_text_changed (GtkTextBuffer  *buffer,
  39                   GtkCssProvider *provider)
  40 {
  41   GtkTextIter start, end;
  42   char *text;
  43
  44   gtk_text_buffer_get_start_iter (buffer, &start);
  45   gtk_text_buffer_get_end_iter (buffer, &end);
  46   gtk_text_buffer_remove_all_tags (buffer, &start, &end);
  47
  48   text = gtk_text_buffer_get_text (buffer, &start, &end, FALSE);
  49   gtk_css_provider_load_from_data (provider, text, -1, NULL);
  50   g_free (text);
  51
  52   gtk_style_context_reset_widgets (gdk_screen_get_default ());
  53 }
  54
  55 static void
  56 apply_css (GtkWidget *widget, GtkStyleProvider *provider)
  57 {
  58   gtk_style_context_add_provider (gtk_widget_get_style_context (widget), provider, G_MAXUINT);
  59   if (GTK_IS_CONTAINER (widget))
  60     gtk_container_forall (GTK_CONTAINER (widget), (GtkCallback) apply_css, provider);
  61 }
  62
  63 GtkWidget *
  64 do_css_pixbufs (GtkWidget *do_widget)
  65 {
  66   if (!window)
  67     {
  68       GtkWidget *paned, *container, *child;
  69       GtkStyleProvider *provider;
  70       GtkTextBuffer *text;
  71       GBytes *bytes;
  72
  73       window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
  74       gtk_window_set_transient_for (GTK_WINDOW (window), GTK_WINDOW (do_widget));
  75       gtk_window_set_default_size (GTK_WINDOW (window), 400, 300);
  76       g_signal_connect (window, "destroy",
  77                         G_CALLBACK (gtk_widget_destroyed), &window);
  78
  79       paned = gtk_paned_new (GTK_ORIENTATION_VERTICAL);
  80       gtk_container_add (GTK_CONTAINER (window), paned);
  81
  82       /* Need a filler so we get a handle */
  83       child = gtk_box_new (GTK_ORIENTATION_VERTICAL, 0);
  84       gtk_container_add (GTK_CONTAINER (paned), child);
  85
  86       text = gtk_text_buffer_new (NULL);
  87       gtk_text_buffer_create_tag (text,
  88                                   "warning",
  89                                   "underline", PANGO_UNDERLINE_SINGLE,
  90                                   NULL);
  91       gtk_text_buffer_create_tag (text,
  92                                   "error",
  93                                   "underline", PANGO_UNDERLINE_ERROR,
  94                                   NULL);
  95
  96       provider = GTK_STYLE_PROVIDER (gtk_css_provider_new ());
  97
  98       container = gtk_scrolled_window_new (NULL, NULL);
  99       gtk_container_add (GTK_CONTAINER (paned), container);
 100       child = gtk_text_view_new_with_buffer (text);
 101       gtk_container_add (GTK_CONTAINER (container), child);
 102       g_signal_connect (text,
 103                         "changed",
 104                         G_CALLBACK (css_text_changed),
 105                         provider);
 106
 107       bytes = g_resources_lookup_data ("/css_pixbufs/gtk.css", 0, NULL);
 108       gtk_text_buffer_set_text (text, g_bytes_get_data (bytes, NULL), g_bytes_get_size (bytes));
 109
 110       g_signal_connect (provider,
 111                         "parsing-error",
 112                         G_CALLBACK (show_parsing_error),
 113                         gtk_text_view_get_buffer (GTK_TEXT_VIEW (child)));
 114
 115       apply_css (window, provider);
 116     }
 117
 118   if (!gtk_widget_get_visible (window))
 119     gtk_widget_show_all (window);
 120   else
 121     {
 122       gtk_widget_destroy (window);
 123       window = NULL;
 124     }
 125
 126   return window;
 127 }