[gthumb] shortcuts: added ability to revert to the default shortcut

[Paolo Bacchilega <paobac src gnome org>]

commit abb9466a8a064741dd1205488c0f3127017e5259
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Mon Nov 11 19:16:50 2019 +0100

    shortcuts: added ability to revert to the default shortcut

 data/ui/shortcuts-preferences.ui   |  1 +
 gthumb/dlg-preferences-shortcuts.c | 41 +++++++++++++++++++++++++++++++++++---
 gthumb/resources/gthumb.css        |  6 ++++++
 3 files changed, 45 insertions(+), 3 deletions(-)
---
diff --git a/data/ui/shortcuts-preferences.ui b/data/ui/shortcuts-preferences.ui
index 5a0b827a..1da14f7d 100644
--- a/data/ui/shortcuts-preferences.ui
+++ b/data/ui/shortcuts-preferences.ui
@@ -38,6 +38,7 @@
   </object>
   <object class="GtkSizeGroup" id="column1_size_group"/>
   <object class="GtkSizeGroup" id="column2_size_group"/>
+  <object class="GtkSizeGroup" id="column3_size_group"/>
   <object class="GtkBox" id="preferences_page">
     <property name="visible">True</property>
     <property name="can_focus">False</property>
diff --git a/gthumb/dlg-preferences-shortcuts.c b/gthumb/dlg-preferences-shortcuts.c
index facaacb3..83d7192e 100644
--- a/gthumb/dlg-preferences-shortcuts.c
+++ b/gthumb/dlg-preferences-shortcuts.c
@@ -60,6 +60,7 @@ typedef struct {
        BrowserData *browser_data;
        GthShortcut *shortcut;
        GtkWidget   *accel_label;
+       GtkWidget   *revert_button;
 } RowData;
 
 
@@ -100,14 +101,14 @@ row_data_update_accel_label (RowData *row_data)
                esc_text = g_markup_escape_text (row_data->shortcut->label, -1);
                markup_text = g_strdup_printf ("<b>%s</b>", esc_text);
                gtk_label_set_markup (GTK_LABEL (row_data->accel_label), markup_text);
-               gtk_style_context_add_class (gtk_widget_get_style_context (row_data->accel_label), 
GTK_STYLE_CLASS_DIM_LABEL);
+               gtk_widget_show (row_data->revert_button);
 
                g_free (markup_text);
                g_free (esc_text);
        }
        else {
                gtk_label_set_text (GTK_LABEL (row_data->accel_label), row_data->shortcut->label);
-               gtk_style_context_remove_class (gtk_widget_get_style_context (row_data->accel_label), 
GTK_STYLE_CLASS_DIM_LABEL);
+               gtk_widget_hide (row_data->revert_button);
        }
 }
 
@@ -174,6 +175,19 @@ shortcuts_list_row_activated_cb (GtkListBox    *box,
 }
 
 
+static void
+revert_button_clicked_cb (GtkButton *button,
+                         gpointer   user_data)
+{
+       RowData         *row_data = user_data;
+       guint            keycode;
+       GdkModifierType  modifiers;
+
+       gtk_accelerator_parse (row_data->shortcut->default_accelerator, &keycode, &modifiers);
+       row_data_update_shortcut (row_data, keycode, modifiers);
+}
+
+
 static GtkWidget *
 _new_shortcut_row (GthShortcut *shortcut,
                   BrowserData *data)
@@ -182,6 +196,8 @@ _new_shortcut_row (GthShortcut *shortcut,
        RowData   *row_data;
        GtkWidget *box;
        GtkWidget *label;
+       GtkWidget *button_box;
+       GtkWidget *button;
 
        row = gtk_list_box_row_new ();
        row_data = row_data_new (data, shortcut);
@@ -200,11 +216,30 @@ _new_shortcut_row (GthShortcut *shortcut,
        row_data->accel_label = label = gtk_label_new ("");
        gtk_label_set_xalign (GTK_LABEL (label), 0.0);
        gtk_widget_set_margin_end (label, 12);
+       gtk_style_context_add_class (gtk_widget_get_style_context (label), GTK_STYLE_CLASS_DIM_LABEL);
        gtk_size_group_add_widget (GTK_SIZE_GROUP (gtk_builder_get_object (data->builder, 
"column2_size_group")), label);
        gtk_box_pack_start (GTK_BOX (box), label, FALSE, FALSE, 0);
-       row_data_update_accel_label (row_data);
+
+       button_box = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 0);
+       gtk_widget_set_margin_start (button_box, 12);
+       gtk_widget_set_margin_end (button_box, 12);
+       gtk_size_group_add_widget (GTK_SIZE_GROUP (gtk_builder_get_object (data->builder, 
"column3_size_group")), button_box);
+       gtk_box_pack_start (GTK_BOX (box), button_box, FALSE, FALSE, 0);
+
+       row_data->revert_button = button = gtk_button_new_from_icon_name ("edit-clear-symbolic", 
GTK_ICON_SIZE_MENU);
+       gtk_button_set_relief (GTK_BUTTON (button), GTK_RELIEF_NONE);
+       gtk_widget_set_tooltip_text (button, _("Revert"));
+       gtk_style_context_add_class (gtk_widget_get_style_context (button), "circular");
+       gtk_style_context_add_class (gtk_widget_get_style_context (button), "revert-shortcut-button");
+       gtk_box_pack_start (GTK_BOX (button_box), button, FALSE, FALSE, 0);
 
        gtk_widget_show_all (row);
+       row_data_update_accel_label (row_data);
+
+       g_signal_connect (row_data->revert_button,
+                         "clicked",
+                         G_CALLBACK (revert_button_clicked_cb),
+                         row_data);
 
        return row;
 }
diff --git a/gthumb/resources/gthumb.css b/gthumb/resources/gthumb.css
index 4294fe32..66f9b122 100644
--- a/gthumb/resources/gthumb.css
+++ b/gthumb/resources/gthumb.css
@@ -168,3 +168,9 @@ GthToolbox .header-bar,
 .void-view {
        opacity: 0.12;
 }
+
+/* -- revert shortcut button -- */
+
+.revert-shortcut-button {
+       padding: 0;
+}