Thuban/Model/session.py

# Copyright (c) 2001, 2002 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, FILENAME_CHANGED, \
     LAYERS_CHANGED, MAP_PROJECTION_CHANGED, \
     LAYER_LEGEND_CHANGED, LAYER_PROJECTION_CHANGED, LAYER_VISIBILITY_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.
    """

    # message channels that have to be forwarded from maps contained in
    # the session.
    forwarded_channels = (
        # map specific channels
        MAP_PROJECTION_CHANGED,
        LAYERS_CHANGED,

        # layer channels forwarded by the map
        LAYER_PROJECTION_CHANGED,
        LAYER_LEGEND_CHANGED,
        LAYER_VISIBILITY_CHANGED)

    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 self.forwarded_channels:
            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"""
    import os
    session = Session('unnamed session')
    session.SetFilename(None)
    session.AddMap(Map('unnamed map'))
    session.UnsetModified()
    return session
1	# Copyright (c) 2001, 2002 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, FILENAME_CHANGED, \
13	LAYERS_CHANGED, MAP_PROJECTION_CHANGED, \
14	LAYER_LEGEND_CHANGED, LAYER_PROJECTION_CHANGED, LAYER_VISIBILITY_CHANGED
15
16	from base import TitledObject, Modifiable
17
18	from map import Map
19
20
21	class Session(TitledObject, Modifiable):
22
23	"""A complete session.
24
25	A Session consists of arbitrary numbers of maps and tables
26
27	Session objects send the following events:
28
29	TITLE_CHANGED -- The title has changed. Parameters: the session.
30
31	FILENAME_CHANGED -- The filename has changed. No parameters.
32
33	MAPS_CHANGED -- Maps were added, removed.
34
35	LAYERS_CHANGED -- Same as the map's event of the same name.
36	It's simply resent from the session to make
37	subscriptions easier.
38	"""
39
40	# message channels that have to be forwarded from maps contained in
41	# the session.
42	forwarded_channels = (
43	# map specific channels
44	MAP_PROJECTION_CHANGED,
45	LAYERS_CHANGED,
46
47	# layer channels forwarded by the map
48	LAYER_PROJECTION_CHANGED,
49	LAYER_LEGEND_CHANGED,
50	LAYER_VISIBILITY_CHANGED)
51
52	def __init__(self, title):
53	TitledObject.__init__(self, title)
54	Modifiable.__init__(self)
55	self.filename = None
56	self.maps = []
57	self.tables = []
58
59	def SetFilename(self, filename):
60	self.filename = filename
61	self.changed(FILENAME_CHANGED)
62
63	def Maps(self):
64	return self.maps
65
66	def HasMaps(self):
67	return len(self.maps) > 0
68
69	def AddMap(self, map):
70	self.maps.append(map)
71	for channel in self.forwarded_channels:
72	map.Subscribe(channel, self.forward, channel)
73	self.changed(MAPS_CHANGED)
74
75	def Destroy(self):
76	for map in self.maps:
77	map.Destroy()
78	self.maps = []
79	self.tables = []
80	Publisher.Destroy(self)
81
82	def forward(self, *args):
83	"""Reissue events"""
84	if len(args) > 1:
85	args = (args[-1],) + args[:-1]
86	apply(self.issue, args)
87
88	def WasModified(self):
89	"""Return true if the session or one of the maps was modified"""
90	if self.modified:
91	return 1
92	else:
93	for map in self.maps:
94	if map.WasModified():
95	return 1
96	return 0
97
98	def UnsetModified(self):
99	"""Unset the modified flag of the session and the maps"""
100	Modifiable.UnsetModified(self)
101	for map in self.maps:
102	map.UnsetModified()
103
104
105
106	def create_empty_session():
107	"""Return an empty session useful as a starting point"""
108	import os
109	session = Session('unnamed session')
110	session.SetFilename(None)
111	session.AddMap(Map('unnamed map'))
112	session.UnsetModified()
113	return session
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svn:keywords	Author Date Id Revision