Index: trunk/src/extobj_helper.h
===================================================================
--- trunk/src/extobj_helper.h	(revision 28909)
+++ trunk/src/extobj_helper.h	(revision 28910)
@@ -27,6 +27,8 @@
 #include "obj_subc.h"
 #include "conf_core.h"
 #include "hid_inlines.h"
+#include "hid_dad.h"
+#include "change.h"
 #include "undo.h"
 
 /*** API ***/
@@ -124,3 +126,45 @@
 	pcb_render->draw_line(pcb_draw_out.fgGC, x, y + unit, x + unit/2, y + unit);
 	pcb_render->draw_line(pcb_draw_out.fgGC, x, y + unit/2, x + unit/3, y + unit/2);
 }
+
+/*** dialog box build ***/
+
+PCB_INLINE void pcb_exto_dlg_coord_cb(void *hid_ctx, void *caller_data, pcb_hid_attribute_t *attr)
+{
+	pcb_subc_t *subc = caller_data;
+	pcb_board_t *pcb;
+	pcb_data_t *data;
+	char tmp[128];
+
+	if (subc->parent_type != PCB_PARENT_DATA)
+		return;
+	data = subc->parent.data;
+	if (data->parent_type != PCB_PARENT_BOARD)
+		return;
+	pcb = data->parent.board;
+
+	pcb_snprintf(tmp, sizeof(tmp), "%$mm", attr->val.crd);
+	pcb_uchg_attr(pcb, (pcb_any_obj_t *)subc, (char *)attr->user_data, tmp);
+	pcb_trace("chg: %s\n", (char *)attr->user_data);
+	pcb_gui->invalidate_all(pcb_gui);
+}
+
+#define pcb_exto_dlg_coord(dlg, subc, vis_name, attr_name, help) \
+do { \
+	double d; \
+	pcb_coord_t currval = 0; \
+	const pcb_unit_t *unit_out; \
+	int wid; \
+	char *sval = pcb_attribute_get(&subc->Attributes, attr_name); \
+	if (sval != NULL) \
+		pcb_get_value_unit(sval, NULL, 0, &d, &unit_out); \
+	currval = d; \
+	PCB_DAD_LABEL(dlg, vis_name); \
+		if (help != NULL) PCB_DAD_HELP(dlg, help); \
+	PCB_DAD_COORD(dlg, ""); \
+		if (help != NULL) PCB_DAD_HELP(dlg, help); \
+		PCB_DAD_CHANGE_CB(dlg, pcb_exto_dlg_coord_cb); \
+		wid = PCB_DAD_CURRENT(dlg); \
+		dlg[wid].user_data = (void *)attr_name; \
+		PCB_DAD_DEFAULT_NUM(dlg, currval); \
+} while(0)
Index: trunk/src_plugins/exto_std/exto_std.c
===================================================================
--- trunk/src_plugins/exto_std/exto_std.c	(revision 28909)
+++ trunk/src_plugins/exto_std/exto_std.c	(revision 28910)
@@ -40,6 +40,7 @@
 #include "extobj_helper.h"
 #include "conf_core.h"
 #include "hid_inlines.h"
+#include "hid_dad.h"
 
 static const char *exto_std_cookie = "exto_std plugin";
 
Index: trunk/src_plugins/exto_std/line_of_vias.c
===================================================================
--- trunk/src_plugins/exto_std/line_of_vias.c	(revision 28909)
+++ trunk/src_plugins/exto_std/line_of_vias.c	(revision 28910)
@@ -31,6 +31,8 @@
 #include "../src_plugins/lib_compat_help/pstk_compat.h"
 
 typedef struct {
+	PCB_DAD_DECL_NOINIT(dlg)
+	int gui_active;
 	pcb_coord_t pitch;
 	pcb_coord_t clearance;
 } line_of_vias;
@@ -37,8 +39,13 @@
 
 static void pcb_line_of_vias_del_pre(pcb_subc_t *subc)
 {
+	line_of_vias *lov = subc->extobj_data;
 	pcb_trace("LoV del_pre\n");
-	free(subc->extobj_data);
+
+	if ((lov != NULL) && (lov->gui_active))
+		PCB_DAD_FREE(lov->dlg);
+
+	free(lov);
 	subc->extobj_data = NULL;
 }
 
@@ -282,9 +289,44 @@
 	return subc;
 }
 
+
+static void pcb_line_of_vias_close_cb(void *caller_data, pcb_hid_attr_ev_t ev)
+{
+	pcb_subc_t *subc = caller_data;
+	line_of_vias *lov = subc->extobj_data;
+
+	PCB_DAD_FREE(lov->dlg);
+	lov->gui_active = 0;
+}
+
 static void pcb_line_of_vias_gui_propedit(pcb_subc_t *subc)
 {
+	pcb_hid_dad_buttons_t clbtn[] = {{"Close", 0}, {NULL, 0}};
+	line_of_vias *lov;
+
 	pcb_trace("LoV: gui propedit\n");
+
+	if (subc->extobj_data == NULL)
+		subc->extobj_data = calloc(sizeof(line_of_vias), 1);
+	lov = subc->extobj_data;
+
+	pcb_trace("LoV: active=%d\n", lov->gui_active);
+	if (lov->gui_active)
+		return; /* do not open another */
+
+	PCB_DAD_BEGIN_VBOX(lov->dlg);
+		PCB_DAD_COMPFLAG(lov->dlg, PCB_HATF_EXPFILL);
+		PCB_DAD_BEGIN_TABLE(lov->dlg, 2);
+			pcb_exto_dlg_coord(lov->dlg, subc, "pitch", "extobj::pitch", "target distance between center of vias");
+			pcb_exto_dlg_coord(lov->dlg, subc, "clearance", "extobj::clearance", "global clarance value on vias");
+		PCB_DAD_END(lov->dlg);
+		PCB_DAD_BUTTON_CLOSES(lov->dlg, clbtn);
+	PCB_DAD_END(lov->dlg);
+
+	/* set up the context */
+	lov->gui_active = 1;
+
+	PCB_DAD_NEW("line_of_vias", lov->dlg, "Line of vias", subc, pcb_false, pcb_line_of_vias_close_cb);
 }
 
 static pcb_extobj_t pcb_line_of_vias = {