Thuban/UI/application.py

# Copyright (C) 2001, 2002, 2003 by Intevation GmbH
# Authors:
# Jan-Oliver Wagner <[email protected]>
# Bernhard Herzog <[email protected]>
#
# This program is free software under the GPL (>=v2)
# Read the file COPYING coming with Thuban for details.

"""
Thuban's application object.
"""

__version__ = "$Revision$"

import sys, os
import os.path

import traceback

from wxPython.wx import *

from Thuban.Lib.connector import Publisher
from Thuban.Lib.fileutil import get_application_dir

from Thuban import _
from Thuban.Model.session import create_empty_session
from Thuban.Model.save import save_session
from Thuban.Model.load import load_session
from Thuban.Model.messages import MAPS_CHANGED
from Thuban.Model.layer import RasterLayer
import Thuban.Model.resource

import view
import tree
import mainwindow

from messages import SESSION_REPLACED


class ThubanApplication(wxApp, Publisher):

    """
    Thuban's application class.

    All wxWindows programs have to have an instance of an application
    class derived from wxApp. In Thuban the application class holds
    references to the main window and the session.
    """

    def OnInit(self):
        self.splash = self.splash_screen()
        if self.splash is not None:
            self.splash.Show()
        self.read_startup_files()
        self.top = self.CreateMainWindow()
        self.SetTopWindow(self.top)
        if self.splash is None:
            self.ShowMainWindow()
        self.session = None
        self.create_session()
        return True

    def OnExit(self):
        """Clean up code.

        Extend this in derived classes if needed.
        """
        self.session.Destroy()
        self.session = None
        Publisher.Destroy(self)

    def read_startup_files(self):
        """Read the startup files."""
        # for now the startup file is ~/.thuban/thubanstart.py
        dir = get_application_dir()
        if os.path.isdir(dir):
            sys.path.append(dir)
            try:
                import thubanstart
            except ImportError:
                tb = sys.exc_info()[2]
                try:
                    if tb.tb_next is not None:
                        # The ImportError exception was raised from
                        # inside the thubanstart module.
                        sys.stderr.write(_("Cannot import the thubanstart"
                                         " module\n"))
                        traceback.print_exc(None, sys.stderr)
                    else:
                        # There's no thubanstart module.
                        sys.stderr.write(_("No thubanstart module available\n"))
                finally:
                    # make sure we delete the traceback object,
                    # otherwise there's be circular references involving
                    # the current stack frame
                    del tb
            except:
                sys.stderr.write(_("Cannot import the thubanstart module\n"))
                traceback.print_exc(None, sys.stderr)
        else:
            # There's no .thuban directory
            sys.stderr.write(_("No ~/.thuban directory\n"))

    def splash_screen(self):
        """Create and return a splash screen.

        This method is called by OnInit to determine whether the
        application should have a splashscreen. If the application
        should display a splash screen override this method in a derived
        class and have it create and return the wxSplashScreen instance.
        The implementation of this method in the derived class should
        also arranged for ShowMainWindow to be called.

        The default implementation simply returns None so that no splash
        screen is shown and ShowMainWindow will be called automatically.
        """
        return None

    def ShowMainWindow(self):
        """Show the main window

        Normally this method is automatically called by OnInit to show
        the main window. However, if the splash_screen method has
        returned a splashscreen it is expected that the derived class
        also arranges for ShowMainWindow to be called at the appropriate
        time.
        """
        self.top.Show(True)

    def CreateMainWindow(self):
        """Create and return the main window for the application.

        Override this in subclasses to instantiate the Thuban mainwindow
        with different parameters or to use a different class for the
        main window.
        """
        msg = (_("This is the wxPython-based Graphical User Interface"
               " for exploring geographic data"))
        return mainwindow.MainWindow(NULL, -1, "Thuban", self, None,
                                     initial_message = msg,
                                     size = (600, 400))

    def Session(self):
        """Return the application's session object"""
        return self.session

    def SetSession(self, session):
        """Make session the new session.

        Issue SESSION_REPLACED after self.session has become the new
        session. After the session has been assigned call
        self.subscribe_session() with the new session and
        self.unsubscribe_session with the old one.
        """
        oldsession = self.session
        self.session = session
        self.subscribe_session(self.session)
        self.issue(SESSION_REPLACED)
        self.maps_changed()
        if oldsession is not None:
            self.unsubscribe_session(oldsession)
            oldsession.Destroy()

    def subscribe_session(self, session):
        """Subscribe to some of the sessions channels.

        Extend this method in derived classes if you need additional
        channels.
        """
        session.Subscribe(MAPS_CHANGED, self.maps_changed)

    def unsubscribe_session(self, session):
        """Unsubscribe from the sessions channels.

        Extend this method in derived classes if you subscribed to
        additional channels in subscribe_session().
        """
        session.Unsubscribe(MAPS_CHANGED, self.maps_changed)

    def create_session(self):
        """Create a default session.

        Override this method in derived classes to instantiate the
        session differently or to use a different session class. Don't
        subscribe to channels here yet. Do that in the
        subscribe_session() method.
        """
        self.SetSession(create_empty_session())

    def OpenSession(self, filename):
        """Open the session in the file named filename"""
        # Make sure we deal with an absolute pathname. Otherwise we can
        # get problems when saving because the saving code expects an
        # absolute directory name
        filename = os.path.abspath(filename)
        session = load_session(filename)
        session.SetFilename(filename)
        session.UnsetModified()
        self.SetSession(session)

        for map in session.Maps():
            for layer in map.Layers():
                if isinstance(layer, RasterLayer) \
                    and not Thuban.Model.resource.has_gdal_support():
                    msg = _("The current session contains Image layers,\n" +
                            "but the GDAL library is not available to " + 
                            "draw them.")
                    dlg = wx.wxMessageDialog(None, 
                                             msg, 
                                             _("Library not available"),
                                             wx.wxOK | wx.wxICON_INFORMATION)
                    print msg
                    dlg.ShowModal()
                    dlg.Destroy()
                    break

    def SaveSession(self):
        save_session(self.session, self.session.filename)

    def maps_changed(self, *args):
        if self.session.HasMaps():
            self.top.SetMap(self.session.Maps()[0])
        else:
            self.top.SetMap(None)
1	# Copyright (C) 2001, 2002, 2003 by Intevation GmbH
2	# Authors:
3	# Jan-Oliver Wagner <[email protected]>
4	# Bernhard Herzog <[email protected]>
5	#
6	# This program is free software under the GPL (>=v2)
7	# Read the file COPYING coming with Thuban for details.
8
9	"""
10	Thuban's application object.
11	"""
12
13	__version__ = "$Revision$"
14
15	import sys, os
16	import os.path
17
18	import traceback
19
20	from wxPython.wx import *
21
22	from Thuban.Lib.connector import Publisher
23	from Thuban.Lib.fileutil import get_application_dir
24
25	from Thuban import _
26	from Thuban.Model.session import create_empty_session
27	from Thuban.Model.save import save_session
28	from Thuban.Model.load import load_session
29	from Thuban.Model.messages import MAPS_CHANGED
30	from Thuban.Model.layer import RasterLayer
31	import Thuban.Model.resource
32
33	import view
34	import tree
35	import mainwindow
36
37	from messages import SESSION_REPLACED
38
39
40
41	class ThubanApplication(wxApp, Publisher):
42
43	"""
44	Thuban's application class.
45
46	All wxWindows programs have to have an instance of an application
47	class derived from wxApp. In Thuban the application class holds
48	references to the main window and the session.
49	"""
50
51	def OnInit(self):
52	self.splash = self.splash_screen()
53	if self.splash is not None:
54	self.splash.Show()
55	self.read_startup_files()
56	self.top = self.CreateMainWindow()
57	self.SetTopWindow(self.top)
58	if self.splash is None:
59	self.ShowMainWindow()
60	self.session = None
61	self.create_session()
62	return True
63
64	def OnExit(self):
65	"""Clean up code.
66
67	Extend this in derived classes if needed.
68	"""
69	self.session.Destroy()
70	self.session = None
71	Publisher.Destroy(self)
72
73	def read_startup_files(self):
74	"""Read the startup files."""
75	# for now the startup file is ~/.thuban/thubanstart.py
76	dir = get_application_dir()
77	if os.path.isdir(dir):
78	sys.path.append(dir)
79	try:
80	import thubanstart
81	except ImportError:
82	tb = sys.exc_info()[2]
83	try:
84	if tb.tb_next is not None:
85	# The ImportError exception was raised from
86	# inside the thubanstart module.
87	sys.stderr.write(_("Cannot import the thubanstart"
88	" module\n"))
89	traceback.print_exc(None, sys.stderr)
90	else:
91	# There's no thubanstart module.
92	sys.stderr.write(_("No thubanstart module available\n"))
93	finally:
94	# make sure we delete the traceback object,
95	# otherwise there's be circular references involving
96	# the current stack frame
97	del tb
98	except:
99	sys.stderr.write(_("Cannot import the thubanstart module\n"))
100	traceback.print_exc(None, sys.stderr)
101	else:
102	# There's no .thuban directory
103	sys.stderr.write(_("No ~/.thuban directory\n"))
104
105	def splash_screen(self):
106	"""Create and return a splash screen.
107
108	This method is called by OnInit to determine whether the
109	application should have a splashscreen. If the application
110	should display a splash screen override this method in a derived
111	class and have it create and return the wxSplashScreen instance.
112	The implementation of this method in the derived class should
113	also arranged for ShowMainWindow to be called.
114
115	The default implementation simply returns None so that no splash
116	screen is shown and ShowMainWindow will be called automatically.
117	"""
118	return None
119
120	def ShowMainWindow(self):
121	"""Show the main window
122
123	Normally this method is automatically called by OnInit to show
124	the main window. However, if the splash_screen method has
125	returned a splashscreen it is expected that the derived class
126	also arranges for ShowMainWindow to be called at the appropriate
127	time.
128	"""
129	self.top.Show(True)
130
131	def CreateMainWindow(self):
132	"""Create and return the main window for the application.
133
134	Override this in subclasses to instantiate the Thuban mainwindow
135	with different parameters or to use a different class for the
136	main window.
137	"""
138	msg = (_("This is the wxPython-based Graphical User Interface"
139	" for exploring geographic data"))
140	return mainwindow.MainWindow(NULL, -1, "Thuban", self, None,
141	initial_message = msg,
142	size = (600, 400))
143
144	def Session(self):
145	"""Return the application's session object"""
146	return self.session
147
148	def SetSession(self, session):
149	"""Make session the new session.
150
151	Issue SESSION_REPLACED after self.session has become the new
152	session. After the session has been assigned call
153	self.subscribe_session() with the new session and
154	self.unsubscribe_session with the old one.
155	"""
156	oldsession = self.session
157	self.session = session
158	self.subscribe_session(self.session)
159	self.issue(SESSION_REPLACED)
160	self.maps_changed()
161	if oldsession is not None:
162	self.unsubscribe_session(oldsession)
163	oldsession.Destroy()
164
165	def subscribe_session(self, session):
166	"""Subscribe to some of the sessions channels.
167
168	Extend this method in derived classes if you need additional
169	channels.
170	"""
171	session.Subscribe(MAPS_CHANGED, self.maps_changed)
172
173	def unsubscribe_session(self, session):
174	"""Unsubscribe from the sessions channels.
175
176	Extend this method in derived classes if you subscribed to
177	additional channels in subscribe_session().
178	"""
179	session.Unsubscribe(MAPS_CHANGED, self.maps_changed)
180
181	def create_session(self):
182	"""Create a default session.
183
184	Override this method in derived classes to instantiate the
185	session differently or to use a different session class. Don't
186	subscribe to channels here yet. Do that in the
187	subscribe_session() method.
188	"""
189	self.SetSession(create_empty_session())
190
191	def OpenSession(self, filename):
192	"""Open the session in the file named filename"""
193	# Make sure we deal with an absolute pathname. Otherwise we can
194	# get problems when saving because the saving code expects an
195	# absolute directory name
196	filename = os.path.abspath(filename)
197	session = load_session(filename)
198	session.SetFilename(filename)
199	session.UnsetModified()
200	self.SetSession(session)
201
202	for map in session.Maps():
203	for layer in map.Layers():
204	if isinstance(layer, RasterLayer) \
205	and not Thuban.Model.resource.has_gdal_support():
206	msg = _("The current session contains Image layers,\n" +
207	"but the GDAL library is not available to " +
208	"draw them.")
209	dlg = wx.wxMessageDialog(None,
210	msg,
211	_("Library not available"),
212	wx.wxOK \| wx.wxICON_INFORMATION)
213	print msg
214	dlg.ShowModal()
215	dlg.Destroy()
216	break
217
218	def SaveSession(self):
219	save_session(self.session, self.session.filename)
220
221	def maps_changed(self, *args):
222	if self.session.HasMaps():
223	self.top.SetMap(self.session.Maps()[0])
224	else:
225	self.top.SetMap(None)
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svn:keywords	Author Date Id Revision