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# Copyright (c) 2001, 2002, 2003 by Intevation GmbH |
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# Authors: |
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# Bernhard Herzog <[email protected]> |
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# |
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# This program is free software under the GPL (>=v2) |
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# Read the file COPYING coming with Thuban for details. |
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|
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""" |
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Various base classes that did not fit elsewhere. |
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""" |
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|
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__version__ = "$Revision$" |
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|
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from Thuban.Lib.connector import Publisher |
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|
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from messages import TITLE_CHANGED, CHANGED |
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|
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class TitledObject: |
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|
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"""Mix-in class for objects that have titles""" |
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|
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def __init__(self, title): |
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self.title = title |
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|
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def Title(self): |
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return self.title |
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|
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def SetTitle(self, title): |
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self.title = title |
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|
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# FIXME: The TitledObject is almost always used in conjunction |
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# with Modifiable (the only exceptions currently are the |
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# tables). We should reall derive TitledObject from modifiable |
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# (would be good for the tables too) but that's taking things a |
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# bit far at the moment. |
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if hasattr(self, 'changed'): |
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self.changed(TITLE_CHANGED, self) |
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|
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class Modifiable(Publisher): |
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|
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"""Class for objects maintaining a modified flag.""" |
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|
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def __init__(self): |
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self.modified = 0 |
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|
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def WasModified(self): |
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"""Return true if the layer was modified""" |
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return self.modified |
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|
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def UnsetModified(self): |
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"""Unset the modified flag. |
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|
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If the modified flag is changed from set to unset by the call, |
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issue a CHANGED message. |
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|
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The modified flag itself is part of the state of the object so |
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some other objects such as a field in the status bar indication |
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whether e.g. the session has changed might be interested in |
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being notified when this flag has changed. |
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""" |
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was_modified = self.modified |
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self.modified = 0 |
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if was_modified: |
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self.issue(CHANGED) |
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|
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def changed(self, channel = None, *args): |
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"""Set the modified flag and optionally issue a message |
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|
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The message is issued on the channel given by channel with args |
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as the arguments. If channel is None issue no message. |
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|
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Subclasses should call this method whenever anything has |
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changed. |
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""" |
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self.modified = 1 |
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if channel is not None: |
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self.issue(channel, *args) |