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'))
    session.UnsetModified()
    return session
1	bh	6	# 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	bh	56	session.UnsetModified()
100	bh	6	return session
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svn:keywords	Author Date Id Revision