[gnome-builder] greeter: show empty state upon no search results

[Christian Hergert <chergert src gnome org>]

commit 972953e05d864976e208340c66f4eb792d3a38b7
Author: Christian Hergert <chergert redhat com>
Date:   Mon Jan 21 19:26:16 2019 -0800

    greeter: show empty state upon no search results

 src/libide/greeter/ide-greeter-workspace.c  | 33 +++++++++++++++++++++++++++++
 src/libide/greeter/ide-greeter-workspace.ui |  9 ++++++++
 2 files changed, 42 insertions(+)
---
diff --git a/src/libide/greeter/ide-greeter-workspace.c b/src/libide/greeter/ide-greeter-workspace.c
index 35cfe89e2..62358edd1 100644
--- a/src/libide/greeter/ide-greeter-workspace.c
+++ b/src/libide/greeter/ide-greeter-workspace.c
@@ -68,6 +68,7 @@ struct _IdeGreeterWorkspace
   GtkActionBar             *projects_action_bar;
   GtkLabel                 *title;
   IdeGreeterButtonsSection *buttons_section;
+  DzlEmptyState            *empty_state;
 
   guint                     selection_mode : 1;
 };
@@ -82,6 +83,31 @@ enum {
 
 static GParamSpec *properties [N_PROPS];
 
+static void
+ide_greeter_workspace_has_match_cb (GtkWidget *widget,
+                                    gpointer   user_data)
+{
+  gboolean *match = user_data;
+
+  if (IDE_IS_GREETER_SECTION (widget))
+    *match |= gtk_widget_get_visible (widget);
+}
+
+static gboolean
+ide_greeter_workspace_has_match (IdeGreeterWorkspace *self)
+{
+  gboolean match = FALSE;
+
+  g_assert (IDE_IS_MAIN_THREAD ());
+  g_assert (IDE_IS_GREETER_WORKSPACE (self));
+
+  gtk_container_foreach (GTK_CONTAINER (self->sections),
+                         ide_greeter_workspace_has_match_cb,
+                         &match);
+
+  return match;
+}
+
 static void
 ide_greeter_workspace_filter_sections (PeasExtensionSet *set,
                                        PeasPluginInfo   *plugin_info,
@@ -120,6 +146,9 @@ ide_greeter_workspace_apply_filter_all (IdeGreeterWorkspace *self)
     peas_extension_set_foreach (self->addins,
                                 ide_greeter_workspace_filter_sections,
                                 self);
+
+  gtk_widget_set_visible (GTK_WIDGET (self->empty_state),
+                          !ide_greeter_workspace_has_match (self));
 }
 
 static void
@@ -591,6 +620,7 @@ ide_greeter_workspace_class_init (IdeGreeterWorkspaceClass *klass)
   gtk_widget_class_bind_template_child (widget_class, IdeGreeterWorkspace, back_button);
   gtk_widget_class_bind_template_child (widget_class, IdeGreeterWorkspace, buttons_section);
   gtk_widget_class_bind_template_child (widget_class, IdeGreeterWorkspace, clone_surface);
+  gtk_widget_class_bind_template_child (widget_class, IdeGreeterWorkspace, empty_state);
   gtk_widget_class_bind_template_child (widget_class, IdeGreeterWorkspace, header_bar);
   gtk_widget_class_bind_template_child (widget_class, IdeGreeterWorkspace, left_box);
   gtk_widget_class_bind_template_child (widget_class, IdeGreeterWorkspace, projects_action_bar);
@@ -676,6 +706,9 @@ ide_greeter_workspace_add_section (IdeGreeterWorkspace *self,
 
   gtk_widget_set_visible (GTK_WIDGET (section),
                           ide_greeter_section_filter (section, NULL));
+
+  gtk_widget_set_visible (GTK_WIDGET (self->empty_state),
+                          !ide_greeter_workspace_has_match (self));
 }
 
 /**
diff --git a/src/libide/greeter/ide-greeter-workspace.ui b/src/libide/greeter/ide-greeter-workspace.ui
index f5753b769..506243fda 100644
--- a/src/libide/greeter/ide-greeter-workspace.ui
+++ b/src/libide/greeter/ide-greeter-workspace.ui
@@ -111,6 +111,15 @@
                                 <property name="visible">true</property>
                               </object>
                             </child>
+                            <child>
+                              <object class="DzlEmptyState" id="empty_state">
+                                <property name="icon-name">edit-find-symbolic</property>
+                                <property name="pixel-size">64</property>
+                                <property name="title" translatable="yes">No Projects Found</property>
+                                <property name="vexpand">true</property>
+                                <property name="valign">center</property>
+                              </object>
+                            </child>
                           </object>
                         </child>
                       </object>