All,
I fixed my problem, and it wasn't how I had described it. It turns out
that I had not checked what type of units Pango was returning font sizes
in, and I had needed to scale by the DPI of the screen. It turns out
that the font description *is* available after you call
gtk_widget_ensure_style in the size_request method.
Sorry about the confusion,
David Brigada
Paul Davis wrote:
On Tue, Mar 24, 2009 at 2:18 PM, David Brigada <brigad@xxxxxxx
<mailto:brigad@xxxxxxx>> wrote:
Hello,
I am writing a graph widget for use in GTK+ applications. I'm
trying to calculate the minimum size for the widget from the text
along the axes of the graph. I use Cairo to draw the text, so I'm
using the cairo_text_extents functions to calculate their sizes.
However, I'm running into a problem where widget->style->font_desc
does not seem to be returning a valid Pango font description. When
I call pango_font_description_get_size on the font_desc, it returns
10 * PANGO_SCALE, which seems to be a default value when the style
isn't initialized. This causes my function to assume the incorrect
font size when calculating its size request. I tried calling
gtk_widget_ensure_style on my widget before accessing the font_desc
element, but that does not help.
at some point the development of GTK (i don't recall precisely where,
but roughly in the vicinity of GTK 2.10), a change was made to the way
styles "bind" to widgets. the key change was that a widget that is not
attached to a GtkWindow doesn't have a style (yet).
i have several examples in my code where i need to do style-based size
computation, and so I create a dummy GtkWindow, pack some (temporary,
representative) widget into it (I do not show the window), then use
ensure_style, and then do the computation, and then delete them both.
the critical change was adding the widget to the (dummy) window. it was
initially a very irritating change, but in the end a pretty trivial code
change.
---p
_______________________________________________
gtk-list mailing list
gtk-list@xxxxxxxxx
http://mail.gnome.org/mailman/listinfo/gtk-list
