[recipes/system-tab: 2/7] Improve button sensitivity handling

[Matthias Clasen <matthiasc src gnome org>]

commit 0ef40c202d36f7793b77e3e7c21f4afa1c99151c
Author: Matthias Clasen <mclasen redhat com>
Date:   Fri Jan 6 07:00:40 2017 -0500

    Improve button sensitivity handling
    
    We never want the link buttons to be sensitive when the insert mark
    is inside an existing link, and adding image links only makes sense
    if there are at least 2 images to switch between.

 src/gr-edit-page.c |   34 +++++++++++++++++++++++++++-------
 1 files changed, 27 insertions(+), 7 deletions(-)
---
diff --git a/src/gr-edit-page.c b/src/gr-edit-page.c
index d716b72..26d7869 100644
--- a/src/gr-edit-page.c
+++ b/src/gr-edit-page.c
@@ -152,8 +152,10 @@ populate_image_flowbox (GrEditPage *page)
         }
 }
 
+static void update_link_button_sensitivity (GrEditPage *page);
+
 static void
-images_changed (GrEditPage *page)
+update_image_button_sensitivity (GrEditPage *page)
 {
         g_autoptr(GArray) images = NULL;
         int length;
@@ -164,8 +166,13 @@ images_changed (GrEditPage *page)
         gtk_widget_set_sensitive (page->remove_image_button, length > 0);
         gtk_widget_set_sensitive (page->rotate_image_left_button, length > 0);
         gtk_widget_set_sensitive (page->rotate_image_right_button, length > 0);
-        gtk_widget_set_sensitive (page->link_image_button, length > 0);
+}
 
+static void
+images_changed (GrEditPage *page)
+{
+        update_image_button_sensitivity (page);
+        update_link_button_sensitivity (page);
         populate_image_flowbox (page);
 }
 
@@ -1046,14 +1053,16 @@ search_finished (GrRecipeSearch *search,
 }
 
 static void
-cursor_moved (GObject    *object,
-              GParamSpec *pspec,
-              GrEditPage *page)
+update_link_button_sensitivity (GrEditPage *page)
 {
-        GtkTextBuffer *buffer = GTK_TEXT_BUFFER (object);
+        GtkTextBuffer *buffer;
         GtkTextIter iter;
         GSList *tags, *s;
         gboolean in_link = FALSE;
+        g_autoptr(GArray) images = NULL;
+        int length;
+
+        buffer = gtk_text_view_get_buffer (GTK_TEXT_VIEW (page->instructions_field));
 
         gtk_text_buffer_get_iter_at_mark (buffer, &iter,
                                           gtk_text_buffer_get_insert (buffer));
@@ -1070,8 +1079,19 @@ cursor_moved (GObject    *object,
         }
         g_slist_free (tags);
 
+        g_object_get (page->images, "images", &images, NULL);
+        length = images->len;
+
         gtk_widget_set_sensitive (page->add_recipe_button, !in_link);
-        gtk_widget_set_sensitive (page->link_image_button, !in_link);
+        gtk_widget_set_sensitive (page->link_image_button, !in_link && (length > 1));
+}
+
+static void
+cursor_moved (GObject    *object,
+              GParamSpec *pspec,
+              GrEditPage *page)
+{
+        update_link_button_sensitivity (page);
 }
 
 static void