Re: gtk box and flow layout

[daa84 <daa84 inbox ru>]

Paul Pogonyshev wrote:
> daa84 wrote:
> > daa84 ?????:
> >   > I start to write my widget with FlowLayout functionality (with
> > > row-breaking). And find next problem:
> > >
> > > gtk_widget_size_request function obtains the preferred size of a widget
> > > gtk_widget_size_allocate assign a size and position to child widgets
> > >
> > > When I fill GtkRequisition structure I send my preferred size of a 
> > > widget (width and height). But in size_allocate function I get new width 
> > > that smaller then first width value. Than it is need to increase size.
> > > How can I do it? Initiate call size_request function another one time or 
> > > change GtkAllocation values.
> > >
> > > This is only my thoughts, I don't test this in code for now.
>
> Initiate new resizing session and be sure to request smaller size next time
> (so that you are not allocated this size again.)  GTK+ is not really suited
> for full-scaled negotiation of size.
>
> Adjusting allocation values will not achieve anything since the container
> (the one which your flow-layout one is in) will not care.
>
> > I solve this problem using gtk_widget_set_size_request function in 
> > allocation function.
>
> This is good as long as the number and size requests of the widgets your
> container contains don't change, which is hard to say in advance, especially
> the latter part.  Less importantly, this will break if theme/font/etc. is
> changed in runtime.
>
> Paul

I write next code for size_allocate function and all work fine (window 
resizing processed normally):



    width = 0;
    rows_count = 1;
    row_height = 1;

    for (cur = g_list_first (priv->buttons_list); cur != NULL; cur = 
g_list_next (cur))
    {
        child = GTK_WIDGET (cur->data);

        if (GTK_WIDGET_VISIBLE (child))
        {
            gtk_widget_size_request (child, &child_req);

            width += child_req.width;

            if (width > allocation->width &&
                    width != child_req.width)
            {
                rows_count++;
                width = child_req.width;
            }

            row_height = MAX (row_height, child_req.height);
        }
    }

    if (priv->rows_count != rows_count ||
            priv->row_height != row_height)
    {
        priv->rows_count = rows_count;
        priv->row_height = row_height;
        gtk_widget_set_size_request (widget, -1, row_height * rows_count);
    }

    width = 0;
    row = 1;
    for (cur = g_list_first (priv->buttons_list); cur != NULL; cur = 
g_list_next (cur))
    {
        child = GTK_WIDGET (cur->data);

        if (GTK_WIDGET_VISIBLE (child))
        {
            gtk_widget_get_child_requisition (child, &child_req);

            width += child_req.width;

            if (width > allocation->width &&
                    width != child_req.width) // this need when width is vary small
            {
                row++;
                width = child_req.width;
            }

            child_alloc.width = child_req.width;
            child_alloc.height = row_height;
            child_alloc.x = allocation->x + width - child_req.width;
            child_alloc.y = allocation->y + row_height * (row - 1);
            gtk_widget_size_allocate (child, &child_alloc);
        }
    }


And no implementation for size_request function.

I don't fully understand what gtk_widget_set_size_request doing, I find 
this solution in gimp sources.

Thanks!

Sorry for my bad English.

--
Andrey Dubravin