mirror of
https://github.com/python/cpython.git
synced 2025-10-31 13:41:24 +00:00
138 lines
4.7 KiB
Python
138 lines
4.7 KiB
Python
"""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. Note that the
|
||
Viewer typically does *not* update itself before calling update_views(),
|
||
since this would cause it to get updated twice.
|
||
|
||
Optionally, Viewers can also implement:
|
||
|
||
- save_options() which takes an optiondb (a dictionary). Store into this
|
||
dictionary any values the Viewer wants to save in the persistent
|
||
~/.pynche file. This dictionary is saved using marshal. The namespace
|
||
for the keys is ad-hoc; make sure you don't clobber some other Viewer's
|
||
keys!
|
||
|
||
- withdraw() which takes no arguments. This is called when Pynche is
|
||
unmapped. All Viewers should implement this.
|
||
|
||
- colordb_changed() which takes a single argument, an instance of
|
||
ColorDB. This is called whenever the color name database is changed and
|
||
gives a chance for the Viewers to do something on those events. See
|
||
ListViewer for details.
|
||
|
||
External Viewers are found dynamically. Viewer modules should have names such
|
||
as FooViewer.py. If such a named module has a module global variable called
|
||
ADDTOVIEW and this variable is true, the Viewer will be added dynamically to
|
||
the `View' menu. ADDTOVIEW contains a string which is used as the menu item
|
||
to display the Viewer (one kludge: if the string contains a `%', this is used
|
||
to indicate that the next character will get an underline in the menu,
|
||
otherwise the first character is underlined).
|
||
|
||
FooViewer.py should contain a class called FooViewer, and its constructor
|
||
should take two arguments, an instance of Switchboard, and optionally a Tk
|
||
master window.
|
||
|
||
"""
|
||
|
||
import sys
|
||
import marshal
|
||
|
||
|
||
|
||
class Switchboard:
|
||
def __init__(self, initfile):
|
||
self.__initfile = initfile
|
||
self.__colordb = None
|
||
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, 'rb')
|
||
self.__optiondb = marshal.load(fp)
|
||
if not isinstance(self.__optiondb, dict):
|
||
print('Problem reading options from file:', initfile,
|
||
file=sys.stderr)
|
||
self.__optiondb = {}
|
||
except (IOError, EOFError, ValueError):
|
||
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 set_colordb(self, colordb):
|
||
self.__colordb = colordb
|
||
for v in self.__views:
|
||
if hasattr(v, 'colordb_changed'):
|
||
v.colordb_changed(colordb)
|
||
self.update_views_current()
|
||
|
||
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)
|
||
# save the name of the file used for the color database. we'll try to
|
||
# load this first.
|
||
self.__optiondb['DBFILE'] = self.__colordb.filename()
|
||
fp = None
|
||
try:
|
||
try:
|
||
fp = open(self.__initfile, 'wb')
|
||
except IOError:
|
||
print('Cannot write options to file:', \
|
||
self.__initfile, file=sys.stderr)
|
||
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
|