[gnome-software] offline updates: GtkTextView in the error message dialog

[Matthias Clasen <matthiasc src gnome org>]

commit 8ad2de9fd201272cd793789676a4fb43060dccd2
Author: Rafal Luzynski <digitalfreak lingonborough com>
Date:   Thu Jun 11 00:35:35 2015 +0200

    offline updates: GtkTextView in the error message dialog
    
    Old GtkExpander removed and replaced by GtkTextView as the new widget
    displaying the update error details. This is the implementation
    of Allan Day's new UI design.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=748936

 src/gs-offline-updates.c |  127 ++++++++++++++++++++++++++++++++-------------
 1 files changed, 90 insertions(+), 37 deletions(-)
---
diff --git a/src/gs-offline-updates.c b/src/gs-offline-updates.c
index d741ec5..712eb1a 100644
--- a/src/gs-offline-updates.c
+++ b/src/gs-offline-updates.c
@@ -24,19 +24,12 @@
 #include <glib/gi18n.h>
 #include <packagekit-glib2/packagekit.h>
 #include <polkit/polkit.h>
-#include <pango/pango-font.h>
 
 #include "gs-cleanup.h"
 #include "gs-offline-updates.h"
 #include "gs-utils.h"
 
 static void
-expander_cb (GtkExpander *expander, GParamSpec *pspec, GtkWindow *dialog)
-{
-       gtk_window_set_resizable (dialog, gtk_expander_get_expanded (expander));
-}
-
-static void
 do_not_expand (GtkWidget *child, gpointer data)
 {
        gtk_container_child_set (GTK_CONTAINER (gtk_widget_get_parent (child)),
@@ -175,6 +168,67 @@ prepare_details (PkError *pk_error)
                return NULL;
 }
 
+static gboolean
+unset_focus (GtkWidget *widget, GdkEvent *event, gpointer data)
+{
+       if (GTK_IS_WINDOW (widget))
+               gtk_window_set_focus(GTK_WINDOW (widget), NULL);
+       return FALSE;
+}
+
+/**
+ * A temporary workaround for https://bugzilla.gnome.org/show_bug.cgi?id=406159
+ * Creates and applies some tags which make the text smaller and add some
+ * margins at each side of the text. Eventually this should be achieved
+ * with some API or CSS attributes which are not yet implemented.
+ * Thanks Matthias Clasen for hints and inspiration.
+ */
+static void
+tmp_apply_tags (GtkTextBuffer *buffer)
+{
+       GtkTextIter start, end, line;
+       gint line_count;
+
+       gtk_text_buffer_create_tag (buffer, "big_gap_before_line",
+                                   "pixels_above_lines", 16, NULL);
+
+       gtk_text_buffer_create_tag (buffer, "big_gap_after_line",
+                                   "pixels_below_lines", 16, NULL);
+
+       gtk_text_buffer_create_tag (buffer, "wide_margins",
+                                   "left_margin", 16, "right_margin", 16,
+                                   NULL);
+
+       gtk_text_buffer_create_tag (buffer, "small",
+                                   "scale", PANGO_SCALE_SMALL, NULL);
+
+       /* Apply to whole text */
+       gtk_text_buffer_get_bounds (buffer, &start, &end);
+       gtk_text_buffer_apply_tag_by_name (buffer, "small", &start, &end);
+       gtk_text_buffer_apply_tag_by_name (buffer, "wide_margins", &start, &end);
+
+       line_count = gtk_text_buffer_get_line_count (buffer);
+       if (line_count <= 1) {
+               /* Apply to the one and only paragraph */
+               gtk_text_buffer_apply_tag_by_name (buffer,
+                                                  "big_gap_before_line", &start, &end);
+               gtk_text_buffer_apply_tag_by_name (buffer,
+                                                  "big_gap_after_line", &start, &end);
+       } else {
+               /* Apply to the first paragraph */
+               gtk_text_buffer_get_iter_at_line (buffer, &line, 1);
+               gtk_text_buffer_apply_tag_by_name (buffer,
+                                                  "big_gap_before_line", &start, &line);
+               /* Is second paragraph the last paragraph? */
+               if (line_count > 2)
+                       gtk_text_buffer_get_iter_at_line (buffer,
+                                                         &line, line_count - 1);
+               /* Apply to the last paragraph */
+               gtk_text_buffer_apply_tag_by_name (buffer,
+                                                  "big_gap_after_line", &line, &end);
+       }
+}
+
 /**
  * insert_details_widget:
  * @dialog: the message dialog where the widget will be inserted
@@ -188,14 +242,15 @@ static void
 insert_details_widget (GtkMessageDialog *dialog, const gchar *details)
 {
        GtkWidget *message_area, *sw, *label;
-       GtkWidget *box, *expander;
-       PangoFontMetrics *metrics;
-       int lineheight;
+       GtkWidget *box, *tv;
+       GtkTextBuffer *buffer;
+       GList *children;
        _cleanup_string_free_ GString *msg = NULL;
 
        if (!details)
                return;
        g_return_if_fail (dialog != NULL);
+       gtk_window_set_resizable (GTK_WINDOW (dialog), TRUE);
 
        msg = g_string_new ("");
        g_string_append_printf (msg, "%s\n\n%s",
@@ -214,42 +269,40 @@ insert_details_widget (GtkMessageDialog *dialog, const gchar *details)
        /* make the labels not expand */
        gtk_container_foreach (GTK_CONTAINER (message_area), do_not_expand, NULL);
 
-       /* TODO: In 3.18 the label will be "Details:" (":" appended) */
-       expander = gtk_expander_new (_("Details"));
-       gtk_widget_set_visible (expander, TRUE);
+       /* Find the secondary label and set its width_chars.   */
+       /* Otherwise the label will tend to expand vertically. */
+       children = gtk_container_get_children (GTK_CONTAINER (message_area));
+       if (children && children->next && GTK_IS_LABEL (children->next->data)) {
+               gtk_label_set_width_chars (GTK_LABEL (children->next->data), 40);
+       }
+
+       label = gtk_label_new (_("Details"));
+       gtk_widget_set_halign (label, GTK_ALIGN_START);
+       gtk_widget_set_visible (label, TRUE);
+       gtk_box_pack_start (GTK_BOX (message_area), label, FALSE, FALSE, 0);
+
        sw = gtk_scrolled_window_new (NULL, NULL);
        gtk_scrolled_window_set_shadow_type (GTK_SCROLLED_WINDOW (sw),
                                             GTK_SHADOW_IN);
        gtk_scrolled_window_set_policy (GTK_SCROLLED_WINDOW (sw),
                                        GTK_POLICY_NEVER,
                                        GTK_POLICY_AUTOMATIC);
+       gtk_scrolled_window_set_min_content_height (GTK_SCROLLED_WINDOW (sw), 150);
        gtk_widget_set_visible (sw, TRUE);
 
-       label = gtk_label_new (msg->str);
-       gtk_label_set_selectable (GTK_LABEL (label), TRUE);
-       gtk_label_set_line_wrap (GTK_LABEL (label), TRUE);
-       gtk_label_set_line_wrap_mode (GTK_LABEL (label), GTK_WRAP_WORD);
-       gtk_widget_set_halign (label, GTK_ALIGN_START);
-       gtk_widget_set_valign (label, GTK_ALIGN_START);
-       gtk_label_set_xalign (GTK_LABEL (label), 0.0);
-       gtk_widget_set_visible (label, TRUE);
+       tv = gtk_text_view_new ();
+       buffer = gtk_text_view_get_buffer (GTK_TEXT_VIEW (tv));
+       gtk_text_view_set_editable (GTK_TEXT_VIEW (tv), FALSE);
+       gtk_text_view_set_wrap_mode (GTK_TEXT_VIEW (tv), GTK_WRAP_WORD);
+       gtk_text_view_set_monospace (GTK_TEXT_VIEW (tv), TRUE);
+       gtk_text_buffer_set_text (buffer, msg->str, -1);
+       tmp_apply_tags (buffer);
+       gtk_widget_set_visible (tv, TRUE);
+
+       gtk_container_add (GTK_CONTAINER (sw), tv);
+       gtk_box_pack_end (GTK_BOX (message_area), sw, TRUE, TRUE, 0);
 
-       /* Setup the minimum size of the text label */
-       gtk_label_set_width_chars (GTK_LABEL (label), 50);
-       metrics = pango_context_get_metrics (
-                       gtk_widget_get_pango_context (label), NULL, NULL);
-       lineheight = PANGO_PIXELS_CEIL (
-                       pango_font_metrics_get_ascent (metrics)
-                       + pango_font_metrics_get_descent (metrics));
-       pango_font_metrics_unref (metrics);
-       gtk_scrolled_window_set_min_content_height(GTK_SCROLLED_WINDOW (sw),
-                                                  5 * lineheight);
-
-       gtk_container_add (GTK_CONTAINER (sw), label);
-       gtk_container_add (GTK_CONTAINER (expander), sw);
-       gtk_box_pack_end (GTK_BOX (message_area), expander, TRUE, TRUE, 0);
-       g_signal_connect (expander, "notify::expanded",
-                         G_CALLBACK (expander_cb), dialog);
+       g_signal_connect (dialog, "map-event", G_CALLBACK (unset_focus), NULL);
 }
 
 void