| """Switchboard class. |
| |
| This class is used to coordinate updates among all Viewers. Every Viewer must |
| conform to the following interface: |
| |
| - it must include a method called update_yourself() which takes three |
| arguments; the red, green, and blue values of the selected color. |
| |
| - When a Viewer selects a color and wishes to update all other Views, it |
| should call update_views() on the Switchboard object. Not that the |
| Viewer typically does *not* update itself before calling update_views(), |
| since this would cause it to get updated twice. |
| """ |
| |
| import sys |
| from types import DictType |
| import marshal |
| |
| class Switchboard: |
| def __init__(self, colordb, initfile): |
| self.__initfile = initfile |
| self.__colordb = colordb |
| self.__optiondb = {} |
| self.__views = [] |
| self.__red = 0 |
| self.__green = 0 |
| self.__blue = 0 |
| self.__canceled = 0 |
| # read the initialization file |
| fp = None |
| if initfile: |
| try: |
| try: |
| fp = open(initfile) |
| self.__optiondb = marshal.load(fp) |
| if type(self.__optiondb) <> DictType: |
| sys.stderr.write( |
| 'Problem reading options from file: %s\n' % |
| initfile) |
| self.__optiondb = {} |
| except (IOError, EOFError): |
| pass |
| finally: |
| if fp: |
| fp.close() |
| |
| def add_view(self, view): |
| self.__views.append(view) |
| |
| def update_views(self, red, green, blue): |
| self.__red = red |
| self.__green = green |
| self.__blue = blue |
| for v in self.__views: |
| v.update_yourself(red, green, blue) |
| |
| def update_views_current(self): |
| self.update_views(self.__red, self.__green, self.__blue) |
| |
| def current_rgb(self): |
| return self.__red, self.__green, self.__blue |
| |
| def colordb(self): |
| return self.__colordb |
| |
| def optiondb(self): |
| return self.__optiondb |
| |
| def save_views(self): |
| # save the current color |
| self.__optiondb['RED'] = self.__red |
| self.__optiondb['GREEN'] = self.__green |
| self.__optiondb['BLUE'] = self.__blue |
| for v in self.__views: |
| if hasattr(v, 'save_options'): |
| v.save_options(self.__optiondb) |
| fp = None |
| try: |
| try: |
| fp = open(self.__initfile, 'w') |
| except IOError: |
| sys.stderr.write('Cannot write options to file: %s\n' % |
| self.__initfile) |
| else: |
| marshal.dump(self.__optiondb, fp) |
| finally: |
| if fp: |
| fp.close() |
| |
| def withdraw_views(self): |
| for v in self.__views: |
| if hasattr(v, 'withdraw'): |
| v.withdraw() |
| |
| def canceled(self, flag=1): |
| self.__canceled = flag |
| |
| def canceled_p(self): |
| return self.__canceled |