From a12a1630736a578de5e0b34a13fb9d24307695fc Mon Sep 17 00:00:00 2001
From: Andre Miranda <andre.miranda@mv.com.br>
Date: Wed, 24 May 2017 14:43:35 -0300
Subject: [PATCH] Single instance feature

---
 lib/screenshooter-actions.c |  2 ++
 lib/screenshooter-global.h  |  1 +
 src/main.c                  | 26 +++++++++++++++++++++++++-
 3 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/lib/screenshooter-actions.c b/lib/screenshooter-actions.c
index 43ee4e2..a9fa048 100644
--- a/lib/screenshooter-actions.c
+++ b/lib/screenshooter-actions.c
@@ -63,6 +63,8 @@ gboolean screenshooter_action_idle (ScreenshotData *sd)
                         G_CALLBACK (cb_help_response), NULL);
       g_signal_connect (dialog, "key-press-event",
                         G_CALLBACK (screenshooter_f1_key), NULL);
+      g_signal_connect_swapped (sd->application, "activate",
+                        G_CALLBACK (gtk_window_present), dialog);
 
       response = gtk_dialog_run (GTK_DIALOG (dialog));
 
diff --git a/lib/screenshooter-global.h b/lib/screenshooter-global.h
index 173f9d4..9dc97a0 100644
--- a/lib/screenshooter-global.h
+++ b/lib/screenshooter-global.h
@@ -55,6 +55,7 @@ typedef struct
   gchar *app;
   gchar *last_user;
   GdkPixbuf *screenshot;
+  GtkApplication *application;
 }
 ScreenshotData;
 
diff --git a/src/main.c b/src/main.c
index c677165..ffea692 100644
--- a/src/main.c
+++ b/src/main.c
@@ -139,7 +139,7 @@ cb_dialog_response (GtkWidget *dialog, gint response, ScreenshotData *sd)
 
 int main (int argc, char **argv)
 {
-  GError *cli_error = NULL;
+  GError *cli_error = NULL, *error = NULL;
   GFile *default_save_dir;
   const gchar *rc_file;
   const gchar *conflict_error =
@@ -279,6 +279,28 @@ int main (int argc, char **argv)
       return EXIT_SUCCESS;
     }
 
+  /* Initialize application to ensure single instance */
+  sd->application = gtk_application_new ("org.xfce.screenshooter", 0);
+
+  g_application_register (G_APPLICATION (sd->application), NULL, &error);
+  if (error != NULL)
+    {
+      g_warning ("Unable to register GApplication: %s", error->message);
+      g_error_free (error);
+      error = NULL;
+    }
+
+  if (g_application_get_is_remote (G_APPLICATION (sd->application)))
+    {
+      g_warning ("An instance of screenshooter is already present");
+      g_application_activate (G_APPLICATION (sd->application));
+      g_object_unref (sd->application);
+
+      g_free (sd);
+
+      return EXIT_SUCCESS;
+    }
+
   /* Read the preferences */
   rc_file = xfce_resource_save_location (XFCE_RESOURCE_CONFIG, "xfce4/xfce4-screenshooter", TRUE);
   screenshooter_read_rc_file (rc_file, sd);
@@ -380,6 +402,8 @@ int main (int argc, char **argv)
                         G_CALLBACK (cb_dialog_response), sd);
       g_signal_connect (dialog, "key-press-event",
                         G_CALLBACK (screenshooter_f1_key), NULL);
+      g_signal_connect_swapped (sd->application, "activate",
+                        G_CALLBACK (gtk_window_present), dialog);
       gtk_widget_show (dialog);
     }
 
-- 
2.13.0