Adding items to tables

[Richard Gipps <rgipps netspace net au>]

Hi all,
         I have been working on some code which adds items to tables 
when a particular event occurs. The problem is that when I add items to 
the table using say a button push, the items are not drawn on the canvas 
until I re-size it. I have tried using  goo_canvas_update(canvas) but 
that does not seem to do the trick. Is there another function I should 
be using? I have included some sample code to put the question into 
context. Note that I have no problem adding these items when not using 
events i.e. before gtk_main() is called.

Regards,
Richard.

#include <gtk/gtk.h>
#include <goocanvas/goocanvas.h>

#define HOMOGENEOUS TRUE
#define NON_HOMOGENEOUS FALSE
#define SPACING 0
#define EXPAND TRUE
#define FILL TRUE
#define PADDING 0

GtkWidget* canvas;
GooCanvasItemModel* table;


static gboolean on_delete_event(GtkWidget* window,GdkEvent* 
event,gpointer unused_data)
{
   return(FALSE); //do not prevent window from being closed (destroyed)
}

static void on_destroy_event(GtkWidget* window,GdkEvent* event,gpointer 
unused_data)
{
   gtk_main_quit();
}

static void on_test_button_1_pressed(GtkButton* button,gpointer* data)
{
  GooCanvasItemModel* rectangle_1;
  GooCanvasItemModel* rectangle_2;
  rectangle_1 = goo_canvas_rect_model_new(table,
                                         0.0, //x
                                         0.0, //y
                                         50.0,  //width,
                                         50.0,  //height
                                         "fill-color","red",
                                         NULL);
   goo_canvas_item_model_set_child_properties(table,
                                              rectangle_1,
                                              "row",0,
                                              "column",0,
                                              NULL);
   rectangle_2 = goo_canvas_rect_model_new(table,
                                         0.0, //x
                                         0.0, //y
                                         50.0,  //width,
                                         50.0,  //height
                                         "fill-color","orange",
                                         NULL);
   goo_canvas_item_model_set_child_properties(table,
                                              rectangle_2,
                                              "row",0,
                                              "column",1,
                                              NULL);
   goo_canvas_update(canvas);
}

int main(int argc,char* argv[])
{
   GtkWidget* window;
   GtkWidget* vbox;
   GtkWidget* hbox;
   GtkWidget* test_button_1;
   GtkWidget* scroll_window;
   GooCanvasItemModel* root;
   GooCanvasItemModel* rectangle_1;
   GooCanvasItemModel* rectangle_2;

   //Initialize GTK+
   gtk_init(&argc, &argv);

   //Create GTK+ the window
   window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
   gtk_widget_set_size_request(window,200,200);
   vbox = gtk_vbox_new(NON_HOMOGENEOUS,SPACING);
   gtk_container_add(GTK_CONTAINER(window),vbox);
   hbox = gtk_hbox_new(HOMOGENEOUS,SPACING);
   gtk_box_pack_start(GTK_BOX(vbox),
                      hbox,
                      FALSE,
                      FALSE,
                      PADDING);
   test_button_1 = gtk_button_new_with_label("Test 1");
   gtk_box_pack_start(GTK_BOX(hbox),
                      test_button_1,
                      TRUE,
                      TRUE,
                      0);
   scroll_window = gtk_scrolled_window_new(NULL,NULL);
   gtk_scrolled_window_set_policy(GTK_SCROLLED_WINDOW(scroll_window),
                                  GTK_POLICY_AUTOMATIC,
                                  GTK_POLICY_AUTOMATIC);
   gtk_box_pack_start(GTK_BOX(vbox),
                      scroll_window,
                      TRUE,
                      TRUE,
                      PADDING);

   //Create canvas
   canvas = goo_canvas_new();
   gtk_container_add(GTK_CONTAINER(scroll_window),canvas);
   root = goo_canvas_group_model_new(NULL,NULL);
   goo_canvas_set_root_item_model(GOO_CANVAS(canvas),root);
   table = goo_canvas_table_model_new(root,
                                      "row-spacing",0.0,
                                      "column-spacing",0.0,
                                      NULL);
   goo_canvas_item_model_translate(table,10,10);
   gtk_widget_show_all(window);

   //Connect signals
   g_signal_connect(G_OBJECT(test_button_1),
                    "clicked",
                    G_CALLBACK(on_test_button_1_pressed),
                    NULL);
   g_signal_connect(G_OBJECT(window),
                    "delete_event",
                    G_CALLBACK(on_delete_event),
                    NULL);
   g_signal_connect(G_OBJECT(window),
                    "destroy",
                    G_CALLBACK(on_destroy_event),
                    NULL);

   //Pass control to the GTK+ main event loop.
   gtk_main();

   return 0;
}