Thuban/Model/extension.py

# Copyright (c) 2001, 2002 by Intevation GmbH
# Authors:
# Jan-Oliver Wagner <[email protected]>
#
# This program is free software under the GPL (>=v2)
# Read the file COPYING coming with Thuban for details.

__version__ = "$Revision$"

from Thuban import _

from messages import EXTENSION_CHANGED, EXTENSION_OBJECTS_CHANGED

from base import TitledObject, Modifiable


class Extension(TitledObject, Modifiable):

    """Represent a extension. A extension is a package of additional
       functionality to Thuban and contains a number of Objects
       that can be freely defined in an extension.
       Each object must a a TitleObject with additional set "object.name".
       Furthermore, each object must implement the methods Subscribe,
       Unsubscribe and Destroy (i.e. derive from Modifiable).

    Extension objects send the following message types:

        EXTENSION_CHANGED -- Something in the extension has changed.

        EXTENSION_OBJECTS_CHANGED -- Something in the objects has changed.

    """

    forwarded_channels = (EXTENSION_CHANGED, EXTENSION_OBJECTS_CHANGED)

    def __init__(self, title):
        """Initialize the extension."""
        TitledObject.__init__(self, title)
        self.objects = []

    def Destroy(self):
        for object in self.objects:
            object.Destroy()
        Modifiable.Destroy(self)

    def AddObject(self, object):
        self.objects.append(object)
        for channel in self.forwarded_channels:
            object.Subscribe(channel, self.forward, channel)
        self.changed(EXTENSION_OBJECTS_CHANGED, self)

    def RemoveObject(self, object):
        for channel in self.forwarded_channels:
            object.Unsubscribe(channel, self.forward, channel)
        self.layers.remove(layer)
        self.changed(EXTENSION_OBJECTS_CHANGED, self)
        object.Destroy()

    def Objects(self):
        return self.objects

    def HasObjects(self):
        return len(self.objects) > 0

    def FindObject(self, title):
        """Find an object by title. If found, return it, else return None."""
        for object in self.objects:
            if object.title == title:
                return object
        return None

    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 something of the extension was modified"""
        if self.modified:
            return 1
        else:
            return 0

    def UnsetModified(self):
        """Unset the modified flag of the extension"""
        Modifiable.UnsetModified(self)

    def TreeInfo(self):
        return (_("Extension: %s") % self.title,
                ["%s: %s" % (object.title, object.name)
                 for object in self.objects])
1	jan	195	# Copyright (c) 2001, 2002 by Intevation GmbH
2			# Authors:
3			# Jan-Oliver Wagner <[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	jan	374	from Thuban import _
11
12	jan	195	from messages import EXTENSION_CHANGED, EXTENSION_OBJECTS_CHANGED
13
14			from base import TitledObject, Modifiable
15
16
17			class Extension(TitledObject, Modifiable):
18
19			"""Represent a extension. A extension is a package of additional
20			functionality to Thuban and contains a number of Objects
21	jan	2355	that can be freely defined in an extension.
22			Each object must a a TitleObject with additional set "object.name".
23			Furthermore, each object must implement the methods Subscribe,
24			Unsubscribe and Destroy (i.e. derive from Modifiable).
25	jan	195
26			Extension objects send the following message types:
27
28			EXTENSION_CHANGED -- Something in the extension has changed.
29
30			EXTENSION_OBJECTS_CHANGED -- Something in the objects has changed.
31
32			"""
33
34			forwarded_channels = (EXTENSION_CHANGED, EXTENSION_OBJECTS_CHANGED)
35
36			def __init__(self, title):
37			"""Initialize the extension."""
38			TitledObject.__init__(self, title)
39			self.objects = []
40
41			def Destroy(self):
42			for object in self.objects:
43			object.Destroy()
44			Modifiable.Destroy(self)
45
46			def AddObject(self, object):
47			self.objects.append(object)
48			for channel in self.forwarded_channels:
49			object.Subscribe(channel, self.forward, channel)
50			self.changed(EXTENSION_OBJECTS_CHANGED, self)
51
52			def RemoveObject(self, object):
53			for channel in self.forwarded_channels:
54			object.Unsubscribe(channel, self.forward, channel)
55			self.layers.remove(layer)
56			self.changed(EXTENSION_OBJECTS_CHANGED, self)
57			object.Destroy()
58
59			def Objects(self):
60			return self.objects
61
62			def HasObjects(self):
63			return len(self.objects) > 0
64
65			def FindObject(self, title):
66			"""Find an object by title. If found, return it, else return None."""
67			for object in self.objects:
68			if object.title == title:
69			return object
70			return None
71
72			def forward(self, *args):
73			"""Reissue events"""
74			if len(args) > 1:
75			args = (args[-1],) + args[:-1]
76			apply(self.issue, args)
77
78			def WasModified(self):
79			"""Return true if something of the extension was modified"""
80			if self.modified:
81			return 1
82			else:
83			return 0
84
85			def UnsetModified(self):
86			"""Unset the modified flag of the extension"""
87			Modifiable.UnsetModified(self)
88	bh	217
89			def TreeInfo(self):
90	jan	374	return (_("Extension: %s") % self.title,
91	bh	217	["%s: %s" % (object.title, object.name)
92			for object in self.objects])
Name	Value
svn:eol-style	native
svn:keywords	Author Date Id Revision