def on_expose_combo_frame(self, widget, event):
        # Init.
        cr = widget.window.cairo_create()
        rect = widget.allocation

        # Draw frame.
        with cairo_disable_antialias(cr):
            cr.set_line_width(1)
            if self.get_sensitive():
                cr.set_source_rgb(*color_hex_to_cairo(ui_theme.get_color("combo_entry_frame").get_color()))
            else:
                cr.set_source_rgb(*color_hex_to_cairo(ui_theme.get_color("disable_frame").get_color()))
            cr.rectangle(rect.x, rect.y, rect.width, rect.height)
            cr.stroke()

            if self.focus_flag:
                color = (ui_theme.get_color("combo_entry_select_background").get_color(), 0.9)
                cr.set_source_rgba(*alpha_color_hex_to_cairo(color))
                cr.rectangle(rect.x, rect.y, rect.width - 1 - self.drop_button_width, rect.height - 1)
                cr.fill()
                cr.set_source_rgba(*alpha_color_hex_to_cairo((ui_theme.get_color("combo_entry_background").get_color(), 0.9)))
                cr.rectangle(rect.x + rect.width - 1 - self.drop_button_width, rect.y, self.drop_button_width, rect.height - 1)
                cr.fill()
            else:
                cr.set_source_rgba(*alpha_color_hex_to_cairo((ui_theme.get_color("combo_entry_background").get_color(), 0.9)))
                cr.rectangle(rect.x, rect.y, rect.width - 1, rect.height - 1)
                cr.fill()

        # Propagate expose to children.
        propagate_expose(widget, event)

        return True

 def render_name(self, cr, rect):
     '''
     Render icon and name of DirItem.
     '''
     # Draw select background.
     if self.is_select:
         draw_vlinear(cr, rect.x ,rect.y, rect.width, rect.height,
                      ui_theme.get_shadow_color("listview_select").get_color_info())
     
     # Init.
     expand_indicator_pixbuf = ui_theme.get_pixbuf("treeview/arrow_right.png").get_pixbuf()
     
     # Draw directory icon.
     draw_pixbuf(cr, self.pixbuf, 
                 rect.x + COLUMN_OFFSET * self.column_index + INDICATOR_PADDING_LEFT + expand_indicator_pixbuf.get_width() + INDICATOR_PADDING_RIGHT + ICON_PADDING_LEFT,
                 rect.y + (rect.height - ICON_SIZE) / 2,
                 )
     
     # Draw directory name.
     draw_text(cr, self.name, 
               rect.x + COLUMN_OFFSET * self.column_index + INDICATOR_PADDING_LEFT + expand_indicator_pixbuf.get_width() + INDICATOR_PADDING_RIGHT + ICON_PADDING_LEFT + ICON_SIZE + ICON_PADDING_RIGHT,
               rect.y,
               rect.width, rect.height)
     
     # Draw drag line.
     if self.drag_line:
         with cairo_disable_antialias(cr):
             cr.set_line_width(1)
             if self.drag_line_at_bottom:
                 cr.rectangle(rect.x, rect.y + rect.height - 1, rect.width, 1)
             else:
                 cr.rectangle(rect.x, rect.y, rect.width, 1)
             cr.fill()

    def expose_spin_bg(self, widget, event):
        '''
        Internal callback for `expose-event` signal.
        '''
        # Init.
        cr = widget.window.cairo_create()
        rect = widget.allocation
        x, y, w, h = rect.x, rect.y, rect.width, rect.height

        # Draw frame.
        with cairo_disable_antialias(cr):
            cr.set_line_width(1)
            if widget.state == gtk.STATE_INSENSITIVE:
                cr.set_source_rgb(*color_hex_to_cairo(ui_theme.get_color("disable_frame").get_color()))
            else:
                cr.set_source_rgb(*color_hex_to_cairo(ui_theme.get_color("combo_entry_frame").get_color()))
            cr.rectangle(rect.x, rect.y, rect.width, rect.height)
            cr.stroke()

            if widget.state == gtk.STATE_INSENSITIVE:
                cr.set_source_rgba(*alpha_color_hex_to_cairo((ui_theme.get_color("disable_background").get_color(), 0.9)))
            else:
                cr.set_source_rgba(*alpha_color_hex_to_cairo((ui_theme.get_color("combo_entry_background").get_color(), 0.9)))
            cr.rectangle(rect.x, rect.y, rect.width - 1, rect.height - 1)
            cr.fill()

        propagate_expose(widget, event)

        return False

    def render(self, cr, rect):
        '''
        IconView interface function.
        
        Render item.
        
        @param cr: Cairo context.
        @param rect: Render rectangle area.
        '''
        # Init.
        draw_x = rect.x + self.padding_x
        draw_y = rect.y + self.padding_y
        
        # Draw color.
        cr.set_source_rgb(*color_hex_to_cairo(self.color))
        cr.rectangle(draw_x, draw_y, self.width, self.height)
        cr.fill()
        
        if self.hover_flag:
            cr.set_source_rgb(*color_hex_to_cairo(ui_theme.get_color("color_item_hover").get_color()))
            cr.rectangle(draw_x, draw_y, self.width, self.height)
            cr.stroke()
        elif self.highlight_flag:
            cr.set_source_rgb(*color_hex_to_cairo(ui_theme.get_color("color_item_highlight").get_color()))
            cr.rectangle(draw_x, draw_y, self.width, self.height)
            cr.stroke()

        # Draw frame.
        with cairo_disable_antialias(cr):    
            cr.set_line_width(1)
            cr.set_source_rgb(*color_hex_to_cairo(ui_theme.get_color("color_item_frame").get_color()))
            cr.rectangle(draw_x, draw_y, self.width, self.height)
            cr.stroke()

    def draw_background(self, cr, rect):
        with cairo_disable_antialias(cr):
            # Draw frame.
            x, y, w, h = rect.x, rect.y, rect.width, rect.height
            cr.set_line_width(1)
            cr.set_source_rgb(*color_hex_to_cairo(
                self.frame_color.get_color()))
            cr.rectangle(x, y, w, h)
            cr.stroke()

            # Draw background.
            cr.set_source_rgba(*alpha_color_hex_to_cairo(
                (ui_theme.get_color("combo_entry_background").get_color(), 0.9)))
            cr.rectangle(x, y, w - 1, h - 1)
            cr.fill()

            # Draw mac dot.
            cr.set_source_rgba(0.5, 0.5, 0.5, 0.8)
            dot_distance = self.width / self.segment_number
            dot_bottom_padding = 18
            for index in range(0, self.last_segment_index):
                draw_text(cr,
                          self.segment_split_char,
                          x + dot_distance * (index + 1) - self.dot_size / 2,
                          y + h - dot_bottom_padding,
                          self.dot_size,
                          self.dot_size,
                          )

 def render_size(self, cr, rect):
     '''
     Render size of DirItem.
     '''
     # Draw select background.
     if self.is_select:
         draw_vlinear(cr, rect.x ,rect.y, rect.width, rect.height,
                      ui_theme.get_shadow_color("listview_select").get_color_info())
     
     # Draw directory size.
     draw_text(cr, self.size_name,
               rect.x,
               rect.y,
               rect.width, 
               rect.height,
               alignment=pango.ALIGN_RIGHT,
               )
     
     # Draw drag line.
     if self.drag_line:
         with cairo_disable_antialias(cr):
             cr.set_line_width(1)
             if self.drag_line_at_bottom:
                 cr.rectangle(rect.x, rect.y + rect.height - 1, rect.width, 1)
             else:
                 cr.rectangle(rect.x, rect.y, rect.width, 1)
             cr.fill()

 def expose_event(self, widget, event):
     cr = widget.window.cairo_create()
     rect = widget.allocation
     with cairo_disable_antialias(cr):
         cr.set_source_rgb(*color_hex_to_cairo(THEME['bg']))
         cr.rectangle(*rect)
         cr.fill()
     propagate_expose(widget, event)
     return True

    def expose_tab_content_align(self, widget, event):
        '''Expose tab content box.'''
        cr = widget.window.cairo_create()
        rect = widget.allocation

        with cairo_disable_antialias(cr):
            cr.set_source_rgb(*color_hex_to_cairo(self.tab_select_frame_color.get_color()))
            cr.rectangle(rect.x + 1, rect.y + 1, rect.width - 2, rect.height - 2)
            cr.stroke()

    def select_button_expose_event(self, widget, event):
        cr = widget.window.cairo_create()
        rect = widget.allocation
        # 
        # get font width/height.
        font_w, font_h = get_text_size(self.text, text_size=self.font_size)
        # draw text.
        x_padding = rect.x + self.ali_padding
        x_padding = max(20, x_padding)

        if self.__selected or self.hover:
            # draw rectangle.
            with cairo_disable_antialias(cr):
                cr.set_source_rgb(*color_hex_to_cairo(self.selected_bg_color))
                cr.rectangle(rect.x, 
                            rect.y, 
                            rect.width, 
                            rect.height)
                cr.fill()
        
            draw_text(cr, self.text,
                    x_padding,
                    rect.y + rect.height/2 - font_h/2,
                    text_size=self.font_size, 
                    text_color=self.selected_font_color)        
        else:
            with cairo_disable_antialias(cr):
                cr.set_source_rgb(*color_hex_to_cairo(self.normal_bg_color))
                cr.rectangle(rect.x, 
                            rect.y, 
                            rect.width, 
                            rect.height)
                cr.fill()

            draw_text(cr, self.text,
                    x_padding,
                    rect.y + rect.height/2 - font_h/2,
                    text_size=self.font_size, 
                    text_color=self.normal_font_color)        
        # set size.
        if font_h > rect.height:
            widget.set_size_request(rect.width, font_h)
        return True

    def expose_droplist_frame(self, widget, event):
        '''Expose droplist frame.'''
        cr = widget.window.cairo_create()        
        rect = widget.allocation

        with cairo_disable_antialias(cr):
            cr.set_line_width(1)
            cr.set_source_rgb(*color_hex_to_cairo(ui_theme.get_color("droplist_frame").get_color()))
            cr.rectangle(rect.x, rect.y, rect.width, rect.height)
            cr.fill()

    def expose_bread_menu_frame(self, widget, event):
        cr = widget.window.cairo_create()
        rect = widget.allocation

        with cairo_disable_antialias(cr):
            outside_border = alpha_color_hex_to_cairo(("#666666", 0.5))
            cr.set_line_width(1)
            cr.set_source_rgba(*outside_border)
            cr.rectangle(rect.x + 1, rect.y + 1, rect.width - 2, rect.height - 2)
            cr.fill()

    def on_expose_alignment(widget, event):
        '''Expose tooltip label.'''
        rect = widget.allocation
        cr = widget.window.cairo_create()

        with cairo_disable_antialias(cr):
            cr.set_line_width(1)
            cr.set_source_rgba(*color_hex_to_cairo(ui_theme.get_color("tooltip_frame").get_color()))
            cr.rectangle(rect.x + 1, rect.y + 1, rect.width - 1, rect.height - 1)
            cr.stroke()
        return True

    def expose_combo_list_frame(self, widget, event):
        cr = widget.window.cairo_create()
        rect = widget.allocation
        cr.set_source_rgb(1, 1, 1)
        cr.rectangle(*rect)
        cr.fill()

        with cairo_disable_antialias(cr):
            cr.set_line_width(1)
            cr.set_source_rgb(*color_hex_to_cairo(ui_theme.get_color("droplist_frame").get_color()))
            cr.rectangle(rect.x + 1, rect.y + 1, rect.width - 1, rect.height - 1)
            cr.stroke()

 def render(self, cr, rect):
     # Init.
     x, y, w, h = rect.x, rect.y, rect.width, rect.height
     
     # Draw background frame.
     with cairo_state(cr):
         cr.rectangle(x, y + 1, w, h - 2)
         cr.rectangle(x + 1, y, w - 2, h)
         cr.clip()
         
         cr.set_source_rgb(*color_hex_to_cairo(ui_theme.get_color("progressbar_background_frame").get_color()))
         cr.rectangle(x, y, w, h)
         cr.set_line_width(1)
         cr.stroke()
         
     # Draw background.
     with cairo_state(cr):
         cr.rectangle(x + 1, y + 1, w - 2, h - 2)
         cr.clip()
         
         draw_vlinear(cr, x + 1, y + 1, w - 2, h - 2,
                      ui_theme.get_shadow_color("progressbar_background").get_color_info(), 
                      )
         
     if self.progress > 0:    
         # Draw foreground frame.
         with cairo_state(cr):
             cr.rectangle(x, y + 1, w, h - 2)
             cr.rectangle(x + 1, y, w - 2, h)
             cr.clip()
         
             cr.set_antialias(cairo.ANTIALIAS_NONE)
             cr.set_source_rgb(*color_hex_to_cairo(ui_theme.get_color("progressbar_foreground_frame").get_color()))
             cr.rectangle(x + 1, y + 1, int(w * self.progress / 100) - 1, h - 1)
             cr.set_line_width(1)
             cr.stroke()
             
         # Draw foreground.
         with cairo_state(cr):
             cr.rectangle(x + 1, y + 1, w - 2, h - 2)
             cr.clip()
             
             draw_vlinear(cr, x + 1, y + 1, int(w * self.progress / 100) - 2, h - 2,
                          ui_theme.get_shadow_color("progressbar_foreground").get_color_info(), 
                          )
         
     # Draw light.
     with cairo_disable_antialias(cr):
         cr.set_source_rgba(1, 1, 1, 0.5)
         cr.rectangle(x + 1, y + 1, w - 2, 1)
         cr.fill()

def draw_window_rectangle(cr, sx, sy, ex, ey, r):
    '''
    Draw window rectangle.
    
    @param cr: Cairo context.
    @param sx: Source x coordinate.
    @param sy: Source y coordinate.
    @param ex: Target x coordinate.
    @param ey: Target x coordinate.
    @param r: Window frame radious.
    '''
    with cairo_disable_antialias(cr):    
        # Set line width.
        cr.set_line_width(1)
        
        # Set OPERATOR_OVER operator.
        cr.set_operator(cairo.OPERATOR_OVER)
        
        cr.move_to(sx + r, sy)  # top line
        cr.line_to(ex - r, sy)
        cr.stroke()
        
        cr.move_to(ex, sy + r)  # right side
        cr.line_to(ex, ey - r)
        cr.stroke()
        
        cr.move_to(ex - r, ey)  # bottom side
        cr.line_to(sx + r, ey)     
        cr.stroke()
        
        cr.move_to(sx, ey - r)  # left side
        cr.line_to(sx, sy + r)        
        cr.stroke()
        
        cr.arc(sx + r, sy + r, r, pi, pi * 3 / 2) # top-left
        cr.stroke()
        
        cr.arc(ex - r, sy + r, r, pi * 3 / 2, pi * 2) # top-right
        cr.stroke()
        
        cr.arc(ex - r, ey - r, r, 0, pi / 2) # bottom-right
        cr.stroke()
        
        cr.arc(sx + r, ey - r, r, pi / 2, pi) # bottom-left
        cr.stroke()

    def expose_tab_content_align(self, widget, event):
        '''
        Internal function to `expose-event` signal.
        '''
        cr = widget.window.cairo_create()
        rect = widget.allocation

        with cairo_disable_antialias(cr):
            cr.rectangle(rect.x, rect.y, sum(self.tab_title_widths[0:self.tab_index]), rect.height)
            cr.rectangle(rect.x + sum(self.tab_title_widths[0:self.tab_index + 1]), 
                         rect.y, 
                         rect.width - sum(self.tab_title_widths[0:self.tab_index + 1]), 
                         rect.height)
            cr.clip()
            
            cr.set_source_rgb(*color_hex_to_cairo(self.tab_select_frame_color.get_color()))
            cr.rectangle(rect.x, rect.y, rect.width, rect.height)
            cr.stroke()

    def expose_event(self, widget, event):
        cr = widget.window.cairo_create()
        rect = widget.allocation
        if self.hover or self.steady:
            background_color = THEME['hover']
            text_color = THEME['bg']
            bg_opacity = self.opacity[1]
            content_opacity = self.opacity[3]
            if bg_opacity == 0:
                text_color = THEME['hover']
        else:
            background_color = THEME['bg']
            text_color = self.color
            bg_opacity = self.opacity[0]
            content_opacity = self.opacity[2]
        font_width, font_height = get_text_size(self.text,
                                                text_size=self.font_size)
        x_padding = rect.x + (rect.width - font_width) / 2
        y_padding = rect.y + (rect.height - font_height) / 2
        with cairo_disable_antialias(cr):
            cr.set_source_rgba(*alpha_color_hex_to_cairo(
                (background_color, bg_opacity)))
            cr.rectangle(rect.x,
                         rect.y,
                         rect.width,
                         rect.height)
            cr.fill()
        if self.border:
            draw_border(cr, rect=rect, pos=(1, 1, 0, 0))

        if self.icon:
            draw_icon(cr, self.symbol, text_color, rect,
                      opacity=content_opacity)
        else:
            draw_text(cr, self.text,
                      x_padding,
                      y_padding,
                      text_size=self.font_size,
                      text_color=text_color)

        if font_height > rect.height:
            widget.set_size_request(rect.width, font_height)
        return True

    def expose_event(self, widget, event):
        self.set_size_request(*self.size)
        cr = widget.window.cairo_create()
        rect = widget.allocation
        font_width, font_height = get_text_size("Loading ...",
                                                text_size=20)

        with cairo_disable_antialias(cr):
            cr.set_source_rgb(*color_hex_to_cairo(THEME['bg']))
            cr.rectangle(*rect)
            cr.fill()

        if self.haveLoadingHint:
            draw_text(cr, "Loading ...",
                      rect.x + (rect.width - font_width) / 2,
                      rect.y + (rect.height - font_height) / 2,
                      text_size=20,
                      text_color=THEME['font_color'])

        propagate_expose(widget, event)
        return True

    def expose_text_entry(self, widget, event):
        '''Callback for `expose-event` signal.'''
        # Init.
        cr = widget.window.cairo_create()
        rect = widget.allocation
        x, y, w, h = rect.x, rect.y, rect.width, rect.height

        # Draw frame.
        with cairo_disable_antialias(cr):
            cr.set_line_width(1)
            cr.set_source_rgb(*color_hex_to_cairo(ui_theme.get_color("combo_entry_frame").get_color()))
            cr.rectangle(rect.x, rect.y, rect.width, rect.height)
            cr.stroke()
            
            cr.set_source_rgba(*alpha_color_hex_to_cairo((ui_theme.get_color("combo_entry_background").get_color(), 0.9)))
            cr.rectangle(rect.x, rect.y, rect.width - 1, rect.height - 1)
            cr.fill()
        
        propagate_expose(widget, event)
        
        return True

 def select_button_expose_event(self, widget, event):
     cr = widget.window.cairo_create()
     rect = widget.allocation
     # 
     if widget.state == gtk.STATE_PRELIGHT:
         # draw rectangle.
         with cairo_disable_antialias(cr):
             cr.set_source_rgb(*color_hex_to_cairo(self.bg_color))
             cr.rectangle(rect.x, 
                         rect.y, 
                         rect.width, 
                         rect.height)
             cr.fill()
     
             cr.set_line_width(1)
             cr.set_source_rgb(*color_hex_to_cairo(self.line_color))
             cr.rectangle(rect.x + 1,
                          rect.y + 1, 
                          rect.width - 2,
                          rect.height - 2)
             cr.stroke()              
     if widget.state == gtk.STATE_INSENSITIVE:
         text_color = "#a6a6a6"
     else:
         text_color = self.text_color
     # get font width/height.
     font_w, font_h = get_text_size(self.text, text_size=self.font_size)
     # draw text.
     x_padding = rect.x + rect.width - font_w - self.ali_padding
     x_padding = max(20, x_padding)
     draw_text(cr, self.text,
               x_padding,
               rect.y + rect.height/2 - font_h/2,
               text_size=self.font_size, 
               text_color=text_color)
     # set size.
     if font_h > rect.height:
         widget.set_size_request(rect.width, font_h)
     return True