[gnome-todo/wip/gbsneto/plugins] plugin-dialog: simplify empty placeholder logic

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 9c24d12438e0b119e8dd8ffc68aaafede76e1afc
Author: Georges Basile Stavracas Neto <georges stavracas gmail com>
Date:   Fri Jan 15 23:34:39 2016 -0200

    plugin-dialog: simplify empty placeholder logic
    
    I totally forgot about gtk_list_box_set_placeholder.

 data/ui/plugin-dialog.ui       |   69 ++++++++++++++++++---------------------
 src/plugin/gtd-plugin-dialog.c |   14 ++------
 2 files changed, 36 insertions(+), 47 deletions(-)
---
diff --git a/data/ui/plugin-dialog.ui b/data/ui/plugin-dialog.ui
index 88fa735..58867da 100644
--- a/data/ui/plugin-dialog.ui
+++ b/data/ui/plugin-dialog.ui
@@ -24,43 +24,6 @@
             <property name="transition_type">slide-left-right</property>
             <property name="interpolate_size">True</property>
             <child>
-              <object class="GtkBox">
-                <property name="visible">True</property>
-                <property name="can_focus">False</property>
-                <property name="halign">center</property>
-                <property name="valign">center</property>
-                <property name="hexpand">True</property>
-                <property name="vexpand">True</property>
-                <property name="orientation">vertical</property>
-                <property name="spacing">12</property>
-                <child>
-                  <object class="GtkImage">
-                    <property name="visible">True</property>
-                    <property name="can_focus">False</property>
-                    <property name="xalign">0.5</property>
-                    <property name="pixel_size">64</property>
-                    <property name="icon_name">preferences-system-symbolic</property>
-                    <style>
-                      <class name="dim-label"/>
-                    </style>
-                  </object>
-                </child>
-                <child>
-                  <object class="GtkLabel">
-                    <property name="visible">True</property>
-                    <property name="can_focus">False</property>
-                    <property name="label" translatable="yes">No extensions found</property>
-                    <style>
-                      <class name="dim-label"/>
-                    </style>
-                  </object>
-                </child>
-              </object>
-              <packing>
-                <property name="name">empty</property>
-              </packing>
-            </child>
-            <child>
               <object class="GtkScrolledWindow">
                 <property name="visible">True</property>
                 <property name="can_focus">True</property>
@@ -127,4 +90,36 @@
       </object>
     </child>
   </template>
+  <object class="GtkBox" id="extension_list_placeholder">
+    <property name="visible">True</property>
+    <property name="can_focus">False</property>
+    <property name="halign">center</property>
+    <property name="valign">center</property>
+    <property name="hexpand">True</property>
+    <property name="vexpand">True</property>
+    <property name="orientation">vertical</property>
+    <property name="spacing">18</property>
+    <child>
+      <object class="GtkImage">
+        <property name="visible">True</property>
+        <property name="can_focus">False</property>
+        <property name="xalign">0.5</property>
+        <property name="pixel_size">64</property>
+        <property name="icon_name">preferences-system-symbolic</property>
+        <style>
+          <class name="dim-label"/>
+        </style>
+      </object>
+    </child>
+    <child>
+      <object class="GtkLabel">
+        <property name="visible">True</property>
+        <property name="can_focus">False</property>
+        <property name="label" translatable="yes">No extensions found</property>
+        <style>
+          <class name="dim-label"/>
+        </style>
+      </object>
+    </child>
+  </object>
 </interface>
diff --git a/src/plugin/gtd-plugin-dialog.c b/src/plugin/gtd-plugin-dialog.c
index d4c70de..17820e9 100644
--- a/src/plugin/gtd-plugin-dialog.c
+++ b/src/plugin/gtd-plugin-dialog.c
@@ -29,6 +29,7 @@ struct _GtdPluginDialog
   GtkDialog           parent;
 
   GtkWidget          *back_button;
+  GtkWidget          *extension_list_placeholder;
   GtkWidget          *frame;
   GtkWidget          *listbox;
   GtkWidget          *stack;
@@ -220,11 +221,9 @@ plugin_unloaded (GtdPluginManager *manager,
                  GtdActivatable   *activatable,
                  GtdPluginDialog  *self)
 {
-  gboolean contains;
   GList *children;
   GList *l;
 
-  contains = FALSE;
   children = gtk_container_get_children (GTK_CONTAINER (self->listbox));
 
   for (l = children; l != NULL; l = l->next)
@@ -236,18 +235,10 @@ plugin_unloaded (GtdPluginManager *manager,
       if (row_activatable == activatable)
         {
           gtk_container_remove (GTK_CONTAINER (self->listbox), l->data);
-          contains = TRUE;
           break;
         }
     }
 
-  /* If there are no extensions left, go back to the 'empty' view */
-  if (g_list_length (children) == 0 ||
-      (g_list_length (children) == 1 && contains))
-    {
-      gtk_stack_set_visible_child_name (GTK_STACK (self->stack), "empty");
-    }
-
   g_free (children);
 }
 
@@ -272,6 +263,7 @@ gtd_plugin_dialog_class_init (GtdPluginDialogClass *klass)
   gtk_widget_class_set_template_from_resource (widget_class, "/org/gnome/todo/ui/plugin-dialog.ui");
 
   gtk_widget_class_bind_template_child (widget_class, GtdPluginDialog, back_button);
+  gtk_widget_class_bind_template_child (widget_class, GtdPluginDialog, extension_list_placeholder);
   gtk_widget_class_bind_template_child (widget_class, GtdPluginDialog, frame);
   gtk_widget_class_bind_template_child (widget_class, GtdPluginDialog, listbox);
   gtk_widget_class_bind_template_child (widget_class, GtdPluginDialog, stack);
@@ -305,6 +297,8 @@ gtd_plugin_dialog_init (GtdPluginDialog *self)
                               sort_extensions,
                               NULL,
                               NULL);
+
+  gtk_list_box_set_placeholder (GTK_LIST_BOX (self->listbox), self->extension_list_placeholder);
 }
 
 GtkWidget*