Thuban/Model/session.py

# Copyright (c) 2001 by Intevation GmbH
# Authors:
# Bernhard Herzog <[email protected]>
#
# This program is free software under the GPL (>=v2)
# Read the file COPYING coming with Thuban for details.

__version__ = "$Revision$"

from Thuban.Lib.connector import Publisher

from messages import MAPS_CHANGED, LAYERS_CHANGED, MAP_PROJECTION_CHANGED, \
     LAYER_LEGEND_CHANGED, FILENAME_CHANGED

from base import TitledObject, Modifiable

from map import Map


class Session(TitledObject, Modifiable):

    """A complete session.

    A Session consists of arbitrary numbers of maps and tables

    Session objects send the following events:

        TITLE_CHANGED -- The title has changed. Parameters: the session.

        FILENAME_CHANGED -- The filename has changed. No parameters.

        MAPS_CHANGED -- Maps were added, removed.

        LAYERS_CHANGED -- Same as the map's event of the same name.
                          It's simply resent from the session to make
                          subscriptions easier.
    """

    def __init__(self, title):
        TitledObject.__init__(self, title)
        Modifiable.__init__(self)
        self.filename = None
        self.maps = []
        self.tables = []

    def SetFilename(self, filename):
        self.filename = filename
        self.changed(FILENAME_CHANGED)

    def Maps(self):
        return self.maps

    def HasMaps(self):
        return len(self.maps) > 0

    def AddMap(self, map):
        self.maps.append(map)
        for channel in (LAYERS_CHANGED, MAP_PROJECTION_CHANGED,
                        LAYER_LEGEND_CHANGED):
            map.Subscribe(channel, self.forward, channel)
        self.changed(MAPS_CHANGED)

    def Destroy(self):
        for map in self.maps:
            map.Destroy()
        self.maps = []
        self.tables = []
        Publisher.Destroy(self)

    def forward(self, *args):
        """Reissue events"""
        if len(args) > 1:
            args = (args[-1],) + args[:-1]
        apply(self.issue, args)

    def WasModified(self):
        """Return true if the session or one of the maps was modified"""
        if self.modified:
            return 1
        else:
            for map in self.maps:
                if map.WasModified():
                    return 1
        return 0

    def UnsetModified(self):
        """Unset the modified flag of the session and the maps"""
        Modifiable.UnsetModified(self)
        for map in self.maps:
            map.UnsetModified()


def create_empty_session():
    """Return an empty session useful as a starting point"""
    session = Session('unnamed session')
    session.SetFilename('unnamed.session')
    session.AddMap(Map('unnamed map'))
    return session
1	# Copyright (c) 2001 by Intevation GmbH
2	# Authors:
3	# Bernhard Herzog <[email protected]>
4	#
5	# This program is free software under the GPL (>=v2)
6	# Read the file COPYING coming with Thuban for details.
7
8	__version__ = "$Revision$"
9
10	from Thuban.Lib.connector import Publisher
11
12	from messages import MAPS_CHANGED, LAYERS_CHANGED, MAP_PROJECTION_CHANGED, \
13	LAYER_LEGEND_CHANGED, FILENAME_CHANGED
14
15	from base import TitledObject, Modifiable
16
17	from map import Map
18
19
20	class Session(TitledObject, Modifiable):
21
22	"""A complete session.
23
24	A Session consists of arbitrary numbers of maps and tables
25
26	Session objects send the following events:
27
28	TITLE_CHANGED -- The title has changed. Parameters: the session.
29
30	FILENAME_CHANGED -- The filename has changed. No parameters.
31
32	MAPS_CHANGED -- Maps were added, removed.
33
34	LAYERS_CHANGED -- Same as the map's event of the same name.
35	It's simply resent from the session to make
36	subscriptions easier.
37	"""
38
39	def __init__(self, title):
40	TitledObject.__init__(self, title)
41	Modifiable.__init__(self)
42	self.filename = None
43	self.maps = []
44	self.tables = []
45
46	def SetFilename(self, filename):
47	self.filename = filename
48	self.changed(FILENAME_CHANGED)
49
50	def Maps(self):
51	return self.maps
52
53	def HasMaps(self):
54	return len(self.maps) > 0
55
56	def AddMap(self, map):
57	self.maps.append(map)
58	for channel in (LAYERS_CHANGED, MAP_PROJECTION_CHANGED,
59	LAYER_LEGEND_CHANGED):
60	map.Subscribe(channel, self.forward, channel)
61	self.changed(MAPS_CHANGED)
62
63	def Destroy(self):
64	for map in self.maps:
65	map.Destroy()
66	self.maps = []
67	self.tables = []
68	Publisher.Destroy(self)
69
70	def forward(self, *args):
71	"""Reissue events"""
72	if len(args) > 1:
73	args = (args[-1],) + args[:-1]
74	apply(self.issue, args)
75
76	def WasModified(self):
77	"""Return true if the session or one of the maps was modified"""
78	if self.modified:
79	return 1
80	else:
81	for map in self.maps:
82	if map.WasModified():
83	return 1
84	return 0
85
86	def UnsetModified(self):
87	"""Unset the modified flag of the session and the maps"""
88	Modifiable.UnsetModified(self)
89	for map in self.maps:
90	map.UnsetModified()
91
92
93
94	def create_empty_session():
95	"""Return an empty session useful as a starting point"""
96	session = Session('unnamed session')
97	session.SetFilename('unnamed.session')
98	session.AddMap(Map('unnamed map'))
99	return session
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svn:keywords	Author Date Id Revision