~jconti/recent-notifications/trunk

"""

RoundedWidgets.py

April 22, 2011

Custom widgets that have rounded edges

"""

import logging

import math

from gi.repository import Gdk, GdkPixbuf, GObject, Gtk

from Theme import Color

logger = logging.getLogger("RoundedWidgets")

# Angles in pi/2 increments 

A0 = 0

A1 = math.pi / 2.0

A2 = math.pi

A3 = 3.0 * math.pi / 2.0

A4 = 2.0 * math.pi

def draw_rounded_box(cr, x, y, width, height, radius):

  """Draws a rounded box to a cairo context, but doesn't fill or stroke it

  so it can be used as a clipping region as well."""

  x1 = x

  y1 = y

  w = width

  h = height

  x2 = x1 + w

  y2 = y1 + h

  r = radius

  cr.move_to(x1 + r, y1)

  cr.line_to(x2 - r, y1)

  cr.arc(x2 - r, y1 + r, r, A3, A4)

  cr.line_to(x2, y2 - r)

  cr.arc(x2 - r, y2 - r, r, A0, A1)

  cr.line_to(x1 + r, y2)

  cr.arc(x1 + r, y2 - r, r, A1, A2)

  cr.line_to(x1, y1 + r)

  cr.arc(x1 + r, y1 + r, r, A2, A3)

class RoundedBox(Gtk.Box):

  """A simple container that draws a solid background with rounded edges"""

  BACKGROUND_COLOR = Color("#fff")

  def __init__(self, radius = 10):

    GObject.GObject.__init__(self)

    self._radius = radius

    self.set_double_buffered(False)

    self.set_redraw_on_allocate(True)

  def set_radius(self, radius):

    """Sets the radius of the curved edges of this box"""

    self._radius = radius

    self.queue_draw()

  def get_radius(self):

    """Gets the radius of the curved edges of this box"""

    return self._radius

  def do_expose_event(self, event):

    """Draws the background and propagates the event to the children"""

    window = self.get_window()

    alloc = self.get_allocation()

    cr = window.cairo_create()

    # Set the clipping region

    cr.rectangle(event.area.x, event.area.y, event.area.width,

        event.area.height)

    cr.clip()

    #TODO: Fix this hack

    color = RoundedBox.BACKGROUND_COLOR

    cr.set_source_rgb(color.red, color.green, color.blue)

    # Draw the rounded box

    draw_rounded_box(cr, alloc.x, alloc.y, alloc.width, alloc.height,

        self._radius)

    cr.fill()

    # Propagate the event to the children

    for child in self.get_children():

      self.propagate_expose(child, event)

class RoundedIcon(Gtk.Widget):

  """Draws a pixbuf with rounded edges"""

  def __init__(self, pixbuf = None, radius = 10):

    GObject.GObject.__init__(self)

    self._pixbuf = pixbuf

    self._radius = radius

    self.set_has_window(False)

    self.set_double_buffered(False)

    self.set_redraw_on_allocate(True)

  def set_from_pixbuf(self, pixbuf):

    """Sets the icon from a pixbuf"""

    self._pixbuf = pixbuf

  def do_expose_event(self, event):

    """Draws the pixbuf"""

    pixbuf = self._pixbuf

    if pixbuf == None:

      return

    window = self.get_window()

    alloc = self.get_allocation()

    cr = window.cairo_create()

    w = pixbuf.get_width()

    h = pixbuf.get_height()

    if alloc.width < w or alloc.height < h:

      self.set_size_request(w, h)

      return

    cr.translate(alloc.x, alloc.y)

    draw_rounded_box(cr, 0, 0,

        w, h,

        self._radius)

    cr.clip()

    Gdk.cairo_set_source_pixbuf(cr, pixbuf, 0, 0)

    cr.paint()