Re: widgets aren't updated

[Michael Torrie <torriem gmail com>]

Ma lin wrote:
> thanks for you help, before the description is not very accurate,
>
> gtk: gtk+-2.10.14
> directfb : DirectFB-1.0.0 (with intel gdl as gfxdriver)
> cairo:  cairo-1.4.2
> pango: pango-1.16.2
> cpu: intel Olo
>
> I used gtk_label_set_label to change my label text in my  button click
> callback,
> but string(old one) not clear , so new one was over old one.
> and I found that new one just cover old one if font width not change,
> otherwise, old one could be show ether.
>
> I have no ideal ,it's pango layout bugs or something else?
> thanks for help

The code appears to function without problem on GTK/X11.  Must be a
problem specific to pango on directfb.  I'm preserving the code below,
so that the other people on the list might take a look.

Michael


> example code:
>
> #include <gtk/gtk.h>
>
> GtkWidget *label;
> static void hello( GtkWidget *widget,
>                    gpointer   data )
> {
>     gchar buffer[10] = {'\0'};
>     static int index=0;
>     index ++;
>     switch (index)
>         {
>             case 1:
>                 strcpy (buffer, "really");
>                 break;
>             case 2:
>                 strcpy (buffer, "cover");
>                 break;
>             case 3:
>                 strcpy (buffer, "right");
>                 break;
>             default:
>                 break;
>         }
>     if (index >=3)
>        index = 0;
>     gtk_label_set_text (GTK_LABEL(label), buffer);
>     g_print ("Hello World\n");
> }
>
> static gboolean delete_event( GtkWidget *widget,
>                               GdkEvent  *event,
>                               gpointer   data )
> {
>     g_print ("delete event occurred\n");
>
>     return FALSE;
> }
>
> static void destroy( GtkWidget *widget,
>                      gpointer   data )
> {
>     gtk_main_quit ();
> }
>
> int main( int   argc,
>           char *argv[] )
> {
>     GtkWidget *window;
>     GtkWidget *button;
>     GtkWidget *box;
>
>     gtk_init (&argc, &argv);
>
>     window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
>     gtk_widget_set_size_request (window, 485, 108);
>
>     g_signal_connect (G_OBJECT (window), "delete_event",
>                     G_CALLBACK (delete_event), NULL);
>
>     g_signal_connect (G_OBJECT (window), "destroy",
>                     G_CALLBACK (destroy), NULL);
>
>     gtk_container_set_border_width (GTK_CONTAINER (window), 10);
>
>     box = gtk_hbox_new (TRUE, 0);
>
>     button = gtk_button_new_with_label ("Hello World");
>
>     g_signal_connect (G_OBJECT (button), "clicked",
>                     G_CALLBACK (hello), NULL);
>
>     gtk_box_pack_start (GTK_BOX (box), button, FALSE, FALSE, 0);
>
>     label = gtk_label_new ("hello world");
>     gtk_box_pack_start (GTK_BOX (box), label, FALSE, FALSE, 0);
>
>     gtk_container_add (GTK_CONTAINER (window), box);
>
>     gtk_widget_show_all (window);
>
>     gtk_main ();
>
>     return 0;
> }