Hi,
I'm trying to make the background of a Desktop Widget semi-transparent using
the cairo graphics library. The widget is written in Python and the only
examples of this I've found are using C (I don't know much C -- I wasn't
even able to apply the examples to Python).
This is the current code (that doesn't work -- the background appears as a
black box)
def __init__(self):
hildondesktop.HomePluginItem.__init__(self)
...
self.connect("screen-changed", self.screen_changed)
self.connect("expose-event", self.expose)
def expose(self, widget, event):
cr = self.window.cairo_create()
cr.set_source_rgba(1.0, 1.0, 1.0, 0.0) # Transparent
# Draw the background
cr.set_operator(cairo.OPERATOR_SOURCE)
cr.paint()
# draw rounded rect
width, height = self.allocation[2], self.allocation[3]
#/* a custom shape, that could be wrapped in a function */
x0 = 0 #/*< parameters like cairo_rectangle */
y0 = 0
radius = min(15, width/2, height/2) #/*< and an approximate curvature
radius */
x1 = x0 + width
y1 = y0 + height
cr.move_to (x0, y0 + radius)
cr.arc (x0 + radius, y0 + radius, radius, 3.14, 1.5 * 3.14)
cr.line_to (x1 - radius, y0)
cr.arc (x1 - radius, y0 + radius, radius, 1.5 * 3.14, 0.0)
cr.line_to (x1 , y1 - radius)
cr.arc (x1 - radius, y1 - radius, radius, 0.0, 0.5 * 3.14)
cr.line_to (x0 + radius, y1)
cr.arc (x0 + radius, y1 - radius, radius, 0.5 * 3.14, 3.14)
cr.close_path ()
bg_color=gtk.gdk.color_parse("#000000")
cr.set_source_rgba (bg_color.red / 65535.0, bg_color.green/65535.0,
bg_color.blue/65535.0, float(32767/65535.0))
cr.fill_preserve ()
# cr.set_source_rgba (0.5, 0.5, 1.0, 0.8)
# cr.stroke ()
def screen_changed(self, widget):
screen = self.get_screen()
colormap = screen.get_rgba_colormap()
self.set_colormap(colormap)
return False
What I'm trying to do is have the widget appear semi-transparent with
rounded corners (like most widgets look) but the above code does not work at
all. I do not know much about cairo and got most of that code from Khertan's
HomeIP widget for Diablo/Chinook and only modified it a little to work with
Maemo 5.
Any help would be greatly appreciated. I've been "banging my head against a
wall" for a while with this one.
--
Best Regards,
Brent Chiodo
_______________________________________________
maemo-developers mailing list
maemo-developers@maemo.org
https://lists.maemo.org/mailman/listinfo/maemo-developers
