[gnome-builder] workbench: notify changes to current perspective

[Christian Hergert <chergert src gnome org>]

commit 32573ccaa4020dce97ba15efa38c41cd5f8cef8f
Author: Christian Hergert <chergert redhat com>
Date:   Thu Jun 16 14:54:03 2016 -0400

    workbench: notify changes to current perspective
    
    This allows workbench addins to be notified when the current perspective
    has changed. This might be useful when we move to a unified headerbar so
    that the addins can enable/disable features.

 libide/ide-workbench-addin.c |   27 ++++++++++++++
 libide/ide-workbench-addin.h |   78 ++++++++++++++++++++++--------------------
 libide/ide-workbench.c       |   22 ++++++++++++
 3 files changed, 90 insertions(+), 37 deletions(-)
---
diff --git a/libide/ide-workbench-addin.c b/libide/ide-workbench-addin.c
index a8be190..e3aee2f 100644
--- a/libide/ide-workbench-addin.c
+++ b/libide/ide-workbench-addin.c
@@ -22,6 +22,12 @@
 
 G_DEFINE_INTERFACE (IdeWorkbenchAddin, ide_workbench_addin, G_TYPE_OBJECT)
 
+static void
+ide_workbench_addin_real_perspective_set (IdeWorkbenchAddin *self,
+                                          IdePerspective    *perspective)
+{
+}
+
 static gchar *
 ide_workbench_addin_real_get_id (IdeWorkbenchAddin *self)
 {
@@ -57,6 +63,7 @@ ide_workbench_addin_default_init (IdeWorkbenchAddinInterface *iface)
   iface->get_id = ide_workbench_addin_real_get_id;
   iface->load = ide_workbench_addin_real_load;
   iface->unload = ide_workbench_addin_real_unload;
+  iface->perspective_set = ide_workbench_addin_real_perspective_set;
 }
 
 /**
@@ -188,3 +195,23 @@ ide_workbench_addin_get_id (IdeWorkbenchAddin *self)
 
   return IDE_WORKBENCH_ADDIN_GET_IFACE (self)->get_id (self);
 }
+
+/**
+ * ide_workbench_addin_perspective_set:
+ * @self: an #IdeWorkbenchAddin
+ * @perspective: An #IdePerspective
+ *
+ * This function is called when the workbench changes the perspective.
+ *
+ * Addins that wish to add buttons to the header bar may want to show or
+ * hide the widgets in this vfunc.
+ */
+void
+ide_workbench_addin_perspective_set (IdeWorkbenchAddin *self,
+                                     IdePerspective    *perspective)
+{
+  g_return_if_fail (IDE_IS_WORKBENCH_ADDIN (self));
+  g_return_if_fail (IDE_IS_PERSPECTIVE (perspective));
+
+  IDE_WORKBENCH_ADDIN_GET_IFACE (self)->perspective_set (self, perspective);
+}
diff --git a/libide/ide-workbench-addin.h b/libide/ide-workbench-addin.h
index 8803b9f..14d38d1 100644
--- a/libide/ide-workbench-addin.h
+++ b/libide/ide-workbench-addin.h
@@ -19,6 +19,7 @@
 #ifndef IDE_WORKBENCH_ADDIN_H
 #define IDE_WORKBENCH_ADDIN_H
 
+#include "ide-perspective.h"
 #include "ide-uri.h"
 #include "ide-workbench.h"
 
@@ -32,45 +33,48 @@ struct _IdeWorkbenchAddinInterface
 {
   GTypeInterface parent;
 
-  gchar    *(*get_id)      (IdeWorkbenchAddin    *self);
-  void      (*load)        (IdeWorkbenchAddin    *self,
-                            IdeWorkbench         *workbench);
-  void      (*unload)      (IdeWorkbenchAddin    *self,
-                            IdeWorkbench         *workbench);
-  gboolean  (*can_open)    (IdeWorkbenchAddin    *self,
-                            IdeUri               *uri,
-                            const gchar          *content_type,
-                            gint                 *priority);
-  void      (*open_async)  (IdeWorkbenchAddin    *self,
-                            IdeUri               *uri,
-                            const gchar          *content_type,
-                            GCancellable         *cancellable,
-                            GAsyncReadyCallback   callback,
-                            gpointer              user_data);
-  gboolean  (*open_finish) (IdeWorkbenchAddin    *self,
-                            GAsyncResult         *result,
-                            GError              **error);
-
+  gchar    *(*get_id)          (IdeWorkbenchAddin    *self);
+  void      (*load)            (IdeWorkbenchAddin    *self,
+                                IdeWorkbench         *workbench);
+  void      (*unload)          (IdeWorkbenchAddin    *self,
+                                IdeWorkbench         *workbench);
+  gboolean  (*can_open)        (IdeWorkbenchAddin    *self,
+                                IdeUri               *uri,
+                                const gchar          *content_type,
+                                gint                 *priority);
+  void      (*open_async)      (IdeWorkbenchAddin    *self,
+                                IdeUri               *uri,
+                                const gchar          *content_type,
+                                GCancellable         *cancellable,
+                                GAsyncReadyCallback   callback,
+                                gpointer              user_data);
+  gboolean  (*open_finish)     (IdeWorkbenchAddin    *self,
+                                GAsyncResult         *result,
+                                GError              **error);
+  void      (*perspective_set) (IdeWorkbenchAddin    *self,
+                                IdePerspective       *perspective);
 };
 
-gchar    *ide_workbench_addin_get_id      (IdeWorkbenchAddin    *self);
-void      ide_workbench_addin_load        (IdeWorkbenchAddin    *self,
-                                           IdeWorkbench         *workbench);
-void      ide_workbench_addin_unload      (IdeWorkbenchAddin    *self,
-                                           IdeWorkbench         *workbench);
-gboolean  ide_workbench_addin_can_open    (IdeWorkbenchAddin    *self,
-                                           IdeUri               *uri,
-                                           const gchar          *content_type,
-                                           gint                 *priority);
-void      ide_workbench_addin_open_async  (IdeWorkbenchAddin    *self,
-                                           IdeUri               *uri,
-                                           const gchar          *content_type,
-                                           GCancellable         *cancellable,
-                                           GAsyncReadyCallback   callback,
-                                           gpointer              user_data);
-gboolean  ide_workbench_addin_open_finish (IdeWorkbenchAddin    *self,
-                                           GAsyncResult         *result,
-                                           GError              **error);
+gchar    *ide_workbench_addin_get_id          (IdeWorkbenchAddin    *self);
+void      ide_workbench_addin_load            (IdeWorkbenchAddin    *self,
+                                               IdeWorkbench         *workbench);
+void      ide_workbench_addin_unload          (IdeWorkbenchAddin    *self,
+                                               IdeWorkbench         *workbench);
+gboolean  ide_workbench_addin_can_open        (IdeWorkbenchAddin    *self,
+                                               IdeUri               *uri,
+                                               const gchar          *content_type,
+                                               gint                 *priority);
+void      ide_workbench_addin_open_async      (IdeWorkbenchAddin    *self,
+                                               IdeUri               *uri,
+                                               const gchar          *content_type,
+                                               GCancellable         *cancellable,
+                                               GAsyncReadyCallback   callback,
+                                               gpointer              user_data);
+gboolean  ide_workbench_addin_open_finish     (IdeWorkbenchAddin    *self,
+                                               GAsyncResult         *result,
+                                               GError              **error);
+void      ide_workbench_addin_perspective_set (IdeWorkbenchAddin    *self,
+                                               IdePerspective       *perspective);
 
 G_END_DECLS
 
diff --git a/libide/ide-workbench.c b/libide/ide-workbench.c
index bad9891..adc2e94 100644
--- a/libide/ide-workbench.c
+++ b/libide/ide-workbench.c
@@ -750,6 +750,23 @@ remove_early_perspectives (gpointer data)
   return G_SOURCE_REMOVE;
 }
 
+static void
+ide_workbench_notify_perspective_set (PeasExtensionSet *set,
+                                      PeasPluginInfo   *plugin_info,
+                                      PeasExtension    *exten,
+                                      gpointer          user_data)
+{
+  IdeWorkbenchAddin *addin = (IdeWorkbenchAddin *)exten;
+  IdeWorkbench *self = user_data;
+
+  g_assert (IDE_IS_WORKBENCH (self));
+  g_assert (PEAS_IS_EXTENSION_SET (set));
+  g_assert (plugin_info != NULL);
+  g_assert (IDE_IS_WORKBENCH_ADDIN (addin));
+
+  ide_workbench_addin_perspective_set (addin, self->perspective);
+}
+
 void
 ide_workbench_set_visible_perspective (IdeWorkbench   *self,
                                        IdePerspective *perspective)
@@ -784,6 +801,11 @@ ide_workbench_set_visible_perspective (IdeWorkbench   *self,
                      remove_early_perspectives,
                      g_object_ref (self));
     }
+
+  if (self->addins != NULL)
+    peas_extension_set_foreach (self->addins,
+                                ide_workbench_notify_perspective_set,
+                                self);
 }
 
 const gchar *