On Sun, Oct 05, 2008 at 10:19:20AM -0400, Pierre Métras wrote: > Hello, > > I've learnt Python and Pygtk writing the Clock activity > (http://wiki.laptop.org/go/Clock_activity) and I'm now adding a new feature > to write the time in full letters to help children learn how to write and > read > it. The clock has different display modes and the default one is to use a SVG > background. I encounter a strange behavior and I don't know where to look at > to correct it. > > The display of the clock activity is composed of a gtk.VBox with a custom > ClockFace widget at the top, and a gtk.Label where I write the current time. > The user can decide to hide/show the written time with an icon in the > toolbar. > > When the Label is not displayed, the XO has enough power to update the > ClockFace widget in less than 1 second, which is nice and what you would > expect from a clock with a hand for seconds. > > But when the user selects to show the time and the code show() the gtk.Label, > the ClockFace widget takes more than 1 second to refresh. The whole activity > becomes unresponsive and it is even difficult to move the mouse to close it. > Gtk timer event every seconds can't follow up... > > I've tracked the problem to these lines: > > if radius != self._cache_radius: > f = open("clock.svg", "rb") > svg_data = f.read() > f.close() > > loader = gtk.gdk.PixbufLoader("svg") > loader.set_size(int(2 * radius), int(2 * radius)) > loader.write(svg_data) > loader.close() > > self._cache_pixbuf = loader.get_pixbuf() > self._cache_radius = radius
Combining the above code block and the following observation ... > As I've said, this strange behavior seems to occur only when the ClockFace > widget paints SVG. In the other display modes, the painting is drawn in the > code. I've seen it in 8.2-761 and still in candidate-767. > ... I suggest that the problem may have something to do with file IO. Are you doing this work on an XO? At present its filesystem has *extremely* poor performance and I would be unsurprised if the described latencies were incurred in opening and reading even a small SVG file. Erik _______________________________________________ Sugar mailing list [email protected] http://lists.laptop.org/listinfo/sugar
