[gtk+] filechooserbutton: Emit 'selection-changed' when changing the selection programmatically

[Federico Mena Quintero <federico src gnome org>]

commit fa4878979e0a72890ca577a210ccd7cf6291dbf0
Author: Federico Mena Quintero <federico gnome org>
Date:   Mon Mar 11 21:54:22 2013 -0600

    filechooserbutton: Emit 'selection-changed' when changing the selection programmatically
    
    We only emitted that signal when the selection changed through the underlying GtkFileChooserDialog.
    
    To do this when the dialog is not active and the selection is changed by the calling program
    (instead of by the user), we need to wait until the GtkFileChooserButton's UI has been updated
    via an async callback from GIO.  So, we keep track of whether an entry point into the
    button's API caused a programmatic change in the selection.
    
    Signed-off-by: Federico Mena Quintero <federico gnome org>

 gtk/gtkfilechooserbutton.c |   37 +++++++++++++++++++++++++++++++++++++
 1 files changed, 37 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtkfilechooserbutton.c b/gtk/gtkfilechooserbutton.c
index d561a8b..0c887e5 100644
--- a/gtk/gtkfilechooserbutton.c
+++ b/gtk/gtkfilechooserbutton.c
@@ -208,6 +208,9 @@ struct _GtkFileChooserButtonPrivate
   guint  active                       : 1;
 
   guint  focus_on_click               : 1;
+
+  /* Whether the next async callback from GIO should emit the "selection-changed" signal */
+  guint  is_changing_selection        : 1;
 };
 
 
@@ -591,6 +594,18 @@ gtk_file_chooser_button_file_chooser_iface_init (GtkFileChooserIface *iface)
   iface->remove_shortcut_folder = gtk_file_chooser_button_remove_shortcut_folder;
 }
 
+static void
+emit_selection_changed_if_changing_selection (GtkFileChooserButton *button)
+{
+  GtkFileChooserButtonPrivate *priv = button->priv;
+
+  if (priv->is_changing_selection)
+    {
+      priv->is_changing_selection = FALSE;
+      g_signal_emit_by_name (button, "selection-changed");
+    }
+}
+
 static gboolean
 gtk_file_chooser_button_set_current_folder (GtkFileChooser    *chooser,
                                            GFile             *file,
@@ -662,6 +677,8 @@ gtk_file_chooser_button_select_file (GtkFileChooser *chooser,
 
       priv->selection_while_inactive = g_object_ref (file);
 
+      priv->is_changing_selection = TRUE;
+
       update_label_and_image (button);
       update_combo_box (button);
 
@@ -692,6 +709,8 @@ gtk_file_chooser_button_unselect_file (GtkFileChooser *chooser,
              priv->selection_while_inactive = NULL;
            }
 
+         priv->is_changing_selection = TRUE;
+
          update_label_and_image (button);
          update_combo_box (button);
        }
@@ -2556,6 +2575,8 @@ update_label_get_info_cb (GCancellable *cancellable,
     g_object_unref (pixbuf);
 
 out:
+  emit_selection_changed_if_changing_selection (button);
+
   g_object_unref (button);
   g_object_unref (cancellable);
 }
@@ -2566,10 +2587,12 @@ update_label_and_image (GtkFileChooserButton *button)
   GtkFileChooserButtonPrivate *priv = button->priv;
   gchar *label_text;
   GFile *file;
+  gboolean done_changing_selection;
 
   file = get_selected_file (button);
 
   label_text = NULL;
+  done_changing_selection = FALSE;
 
   if (priv->update_button_cancellable)
     {
@@ -2607,7 +2630,10 @@ update_label_and_image (GtkFileChooserButton *button)
           _gtk_file_system_volume_unref (volume);
 
           if (label_text)
+           {
+             done_changing_selection = TRUE;
              goto out;
+           }
         }
 
       if (g_file_is_native (file))
@@ -2629,8 +2655,16 @@ update_label_and_image (GtkFileChooserButton *button)
           gtk_image_set_from_pixbuf (GTK_IMAGE (priv->image), pixbuf);
           if (pixbuf)
             g_object_unref (pixbuf);
+
+         done_changing_selection = TRUE;
         }
     }
+  else
+    {
+      /* We know the selection is empty */
+      done_changing_selection = TRUE;
+    }
+
 out:
 
   if (file)
@@ -2646,6 +2680,9 @@ out:
       gtk_label_set_text (GTK_LABEL (priv->label), _(FALLBACK_DISPLAY_NAME));
       gtk_image_set_from_pixbuf (GTK_IMAGE (priv->image), NULL);
     }
+
+  if (done_changing_selection)
+    emit_selection_changed_if_changing_selection (button);
 }