Try to improve multihead behavior by setting DISPLAY variable at several strategic places in the code.

(Old svn revision: 20342)

panel/panel-app.c

@@ -113,6 +113,14 @@ cleanup_panels (void)
         l = g_list_delete_link (l, l);
     }
 
+    for (i = 0; i < panel_app.monitor_list->len; ++i)
+    {
+        XfceMonitor *xmon = g_ptr_array_index (panel_app.monitor_list, i);
+        g_free (xmon->dpyname);
+        g_free (xmon);
+    }
+    g_ptr_array_free (panel_app.monitor_list, TRUE);
+
     for (i = 0; i < panel_app.panel_list->len; ++i)
     {
         Panel *panel = g_ptr_array_index (panel_app.panel_list, i);
@@ -312,6 +320,8 @@ create_monitor_list (void)
 
             gdk_screen_get_monitor_geometry (screen, j, &(monitor->geometry));
 
+            monitor->dpyname = gdk_screen_make_display_name (screen);
+
             g_ptr_array_add (panel_app.monitor_list, monitor);
             
             if (j > 0)
@@ -333,6 +343,8 @@ create_monitor_list (void)
 
             gdk_screen_get_monitor_geometry (screen, j, &(monitor->geometry));
 
+            monitor->dpyname = gdk_screen_make_display_name (screen);
+
             g_ptr_array_add (panel_app.monitor_list, monitor);
 #endif
         }
@@ -573,6 +585,10 @@ panel_app_run (int argc, char **argv)
     g_ptr_array_foreach (panel_app.panel_list, (GFunc)panel_app_init_panel, 
                          NULL);
 
+    /* reset environment */
+    xfce_setenv ("DISPLAY", gdk_display_get_name (gdk_display_get_default ()),
+		 TRUE);
+    
     /* Run Forrest, Run! */
     panel_app.check_id = 
         g_timeout_add (250, (GSourceFunc) check_signal_state, NULL);

panel/panel-app.h

@@ -87,6 +87,7 @@ struct _XfceMonitor
     GdkScreen *screen;
     int num;
     GdkRectangle geometry;
+    char *dpyname;
     guint has_neighbor_left:1;
     guint has_neighbor_right:1;
     guint has_neighbor_above:1;

panel/panel-config.c

@@ -428,6 +428,8 @@ end_element_handler (GMarkupParseContext * context,
         case PROPERTIES:
             if (strcmp ("properties", element_name) == 0)
             {
+                XfceMonitor *xmon;
+                
                 parser->state = PANEL;
                 if (parser->properties_set)
                 {
@@ -440,6 +442,11 @@ end_element_handler (GMarkupParseContext * context,
                         parser->monitor = DefaultScreen (GDK_DISPLAY());
                     }
 
+                    
+                    /* environment */
+                    xmon = panel_app_get_monitor (parser->monitor);
+                    xfce_setenv ("DISPLAY", xmon->dpyname, TRUE);
+    
                     g_object_set (G_OBJECT (parser->current_panel),
                                   "size", parser->size,
                                   "monitor", parser->monitor,

panel/panel.c

@@ -810,9 +810,14 @@ panel_create_item (Panel *panel, const char *name, const char *id)
 {
     PanelPrivate *priv;
     GtkWidget *item = NULL;
+    XfceMonitor *xmon;
 
     priv = panel->priv;
 
+    /* environment */
+    xmon = panel_app_get_monitor (priv->monitor);
+    xfce_setenv ("DISPLAY", xmon->dpyname, TRUE);
+    
     if ((item = xfce_panel_item_manager_create_item (name, id, 
                     priv->size, priv->screen_position)) != NULL)
     {
@@ -835,6 +840,10 @@ panel_create_item (Panel *panel, const char *name, const char *id)
                           G_CALLBACK (_item_start_move), panel);
     }
 
+    /* reset environment */
+    xfce_setenv ("DISPLAY", gdk_display_get_name (gdk_display_get_default ()),
+		 TRUE);
+    
     return item;
 }