[gnome-control-center/wip/hadess/wacom-visibility: 49/50] wacom: Hide Wacom panel when there are no tablets

[Bastien Nocera <hadess src gnome org>]

commit 0e2a4aa2d6224c2bc0090c040596ca422708e580
Author: Bastien Nocera <hadess hadess net>
Date:   Wed May 30 11:54:09 2018 +0200

    wacom: Hide Wacom panel when there are no tablets
    
    Use GsdDeviceManager to monitor libwacom-supported tablets coming and
    going. Hide the Wacom panel from the list when there's no supported
    tablets plugged in.

 panels/wacom/cc-wacom-panel.c | 37 +++++++++++++++++++++++++++++++++++++
 panels/wacom/cc-wacom-panel.h |  2 ++
 shell/cc-panel-loader.c       |  5 ++++-
 3 files changed, 43 insertions(+), 1 deletion(-)
---
diff --git a/panels/wacom/cc-wacom-panel.c b/panels/wacom/cc-wacom-panel.c
index 77a1e261f..82caf9ab0 100644
--- a/panels/wacom/cc-wacom-panel.c
+++ b/panels/wacom/cc-wacom-panel.c
@@ -25,6 +25,8 @@
 #include <gtk/gtk.h>
 #include <glib/gi18n-lib.h>
 
+#include "shell/cc-application.h"
+#include "shell/cc-debug.h"
 #include "cc-wacom-panel.h"
 #include "cc-wacom-page.h"
 #include "cc-wacom-stylus-page.h"
@@ -83,6 +85,41 @@ enum {
        PROP_PARAMETERS
 };
 
+/* Static init function */
+static void
+update_visibility (GsdDeviceManager *manager,
+                  GsdDevice        *device,
+                  gpointer          user_data)
+{
+       CcApplication *application;
+       g_autoptr(GList) devices = NULL;
+       guint i;
+
+       devices = gsd_device_manager_list_devices (manager, GSD_DEVICE_TYPE_TABLET);
+       i = g_list_length (devices);
+
+       /* Set the new visibility */
+       application = CC_APPLICATION (g_application_get_default ());
+       cc_shell_model_set_panel_visibility (cc_application_get_model (application),
+                                            "wacom",
+                                            i > 0 ? CC_PANEL_VISIBLE : CC_PANEL_VISIBLE_IN_SEARCH);
+
+       g_debug ("Wacom panel visible: %s", i > 0 ? "yes" : "no");
+}
+
+void
+cc_wacom_panel_static_init_func (void)
+{
+       GsdDeviceManager *manager;
+
+       manager = gsd_device_manager_get ();
+       g_signal_connect (G_OBJECT (manager), "device-added",
+                         G_CALLBACK (update_visibility), NULL);
+       g_signal_connect (G_OBJECT (manager), "device-removed",
+                         G_CALLBACK (update_visibility), NULL);
+       update_visibility (manager, NULL, NULL);
+}
+
 static CcWacomPage *
 set_device_page (CcWacomPanel *self, const gchar *device_name)
 {
diff --git a/panels/wacom/cc-wacom-panel.h b/panels/wacom/cc-wacom-panel.h
index 430c94381..a5b1e758b 100644
--- a/panels/wacom/cc-wacom-panel.h
+++ b/panels/wacom/cc-wacom-panel.h
@@ -64,6 +64,8 @@ struct _CcWacomPanelClass
   CcPanelClass parent_class;
 };
 
+void cc_wacom_panel_static_init_func (void);
+
 GType cc_wacom_panel_get_type (void) G_GNUC_CONST;
 
 void  cc_wacom_panel_switch_to_panel (CcWacomPanel *self,
diff --git a/shell/cc-panel-loader.c b/shell/cc-panel-loader.c
index 3beba0bfd..6b5c6e3d0 100644
--- a/shell/cc-panel-loader.c
+++ b/shell/cc-panel-loader.c
@@ -68,6 +68,9 @@ extern GType cc_wacom_panel_get_type (void);
 #ifdef BUILD_NETWORK
 extern void cc_wifi_panel_static_init_func (void);
 #endif /* BUILD_NETWORK */
+#ifdef BUILD_WACOM
+extern void cc_wacom_panel_static_init_func (void);
+#endif /* BUILD_WACOM */
 
 #define PANEL_TYPE(name, get_type, init_func) { name, get_type, init_func }
 
@@ -115,7 +118,7 @@ static struct {
   PANEL_TYPE("universal-access", cc_ua_panel_get_type,                   NULL),
   PANEL_TYPE("user-accounts",    cc_user_panel_get_type,                 NULL),
 #ifdef BUILD_WACOM
-  PANEL_TYPE("wacom",            cc_wacom_panel_get_type,                NULL),
+  PANEL_TYPE("wacom",            cc_wacom_panel_get_type,                cc_wacom_panel_static_init_func),
 #endif
 };