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1 ============================
2 wxPython 2.5 Migration Guide
3 ============================
4
5 This document will help explain some of the major changes in wxPython
6 2.5 since the 2.4 series and let you know what you need to do to adapt
7 your programs to those changes. Be sure to also check in the CHANGES_
8 file like usual to see info about the not so major changes and other
9 things that have been added to wxPython.
10
11 .. _CHANGES: CHANGES.html
12
13
14 wxName Change
15 -------------
16
17 The **wxWindows** project and library is now known as
18 **wxWidgets**. Please see here_ for more details.
19
20 .. _here: http://www.wxwidgets.org/name.htm
21
22 This won't really affect wxPython all that much, other than the fact
23 that the wxwindows.org domain name has changed to wxwidgets.org,
24 so mail list, CVS, and etc. addresses have also changed. We're going
25 to try and smooth the transition as much as possible, but I wanted you
26 all to be aware of this change if you run into any issues.
27
28
29
30 Module Initialization
31 ---------------------
32
33 The import-startup-bootstrap process employed by wxPython was changed
34 such that wxWidgets and the underlying gui toolkit are **not**
35 initialized until the wx.App object is created (but before wx.App.OnInit
36 is called.) This was required because of some changes that were made
37 to the C++ wxApp class.
38
39 There are both benefits and potential problems with this change. The
40 benefits are that you can import wxPython without requiring access to
41 a GUI (for checking version numbers, etc.) and that in a
42 multi-threaded environment the thread that creates the app object will
43 now be the GUI thread instead of the one that imports wxPython. Some
44 potential problems are that the C++ side of the "stock-objects"
45 (wx.BLUE_PEN, wx.TheColourDatabase, etc.) are not initialized until
46 the wx.App object is created, so you should not use them until after
47 you have created your wx.App object. If you do then an exception will
48 be raised telling you that the C++ object has not been initialized
49 yet.
50
51 Also, you will probably not be able to do any kind of GUI or bitmap
52 operation unless you first have created an app object, (even on
53 Windows where most anything was possible before.)
54
55 **[Changed in 2.5.2.x]** All the Window and GDI (pen, bitmap, etc.)
56 class constructors and also many toplevel functions and static methods
57 will now check that a wx.App object has already been created and will
58 raise a wx.PyNoAppError exception if not.
59
60
61
62
63 SWIG 1.3
64 --------
65
66 wxPython is now using SWIG 1.3.x from CVS (with several of my own
67 customizations added that I hope to get folded back into the main SWIG
68 distribution.) This has some far reaching ramifications:
69
70 All classes derive from object and so all are now "new-style
71 classes." This also allows you to use mixin classes that are
72 new-style and to use properties, staticmethod, etc.
73
74 Public data members of the C++ classes are wrapped as Python
75 properties using property() instead of using
76 __getattr__/__setattr__ hacks like before. Normally you shouldn't
77 notice any difference, but if you were previously doing something
78 with __getattr__/__setattr__ in derived classes then you may have
79 to adjust things.
80
81 Static C++ methods are wrapped using the staticmethod() feature of
82 Python and so are accessible as ClassName.MethodName as expected.
83 They are still also available as top level functions named like
84 ClassName_MethodName as before.
85
86 The relationship between the wxFoo and wxFooPtr classes have
87 changed for the better. Specifically, all instances that you see
88 will be wx.Foo even if they are created internally using wx.FooPtr,
89 because wx.FooPtr.__init__ will change the instance's __class__ as
90 part of the initialization. If you have any code that checks
91 class type using something like isinstance(obj, wx.FooPtr) you will
92 need to change it to isinstance(obj, wx.Foo).
93
94
95
96 Binding Events
97 --------------
98
99 All of the EVT_* functions are now instances of the wx.PyEventBinder
100 class. They have a __call__ method so they can still be used as
101 functions like before, but making them instances adds some
102 flexibility that I expect to take advantave of in the future.
103
104 wx.EvtHandler (the base class for wx.Window) now has a Bind method that
105 makes binding events to windows a little easier. Here is its
106 definition and docstring::
107
108 def Bind(self, event, handler, source=None, id=wxID_ANY, id2=wxID_ANY):
109 """
110 Bind an event to an event handler.
111
112 event One of the EVT_* objects that specifies the
113 type of event to bind.
114
115 handler A callable object to be invoked when the event
116 is delivered to self. Pass None to disconnect an
117 event handler.
118
119 source Sometimes the event originates from a different window
120 than self, but you still want to catch it in self. (For
121 example, a button event delivered to a frame.) By
122 passing the source of the event, the event handling
123 system is able to differentiate between the same event
124 type from different controls.
125
126 id,id2 Used for menu IDs or for event types that require a
127 range of IDs
128
129 """
130
131 Some examples of its use::
132
133 self.Bind(wx.EVT_SIZE, self.OnSize)
134 self.Bind(wx.EVT_BUTTON, self.OnButtonClick, theButton)
135 self.Bind(wx.EVT_MENU, self.OnExit, id=wx.ID_EXIT)
136
137
138 The wx.Menu methods that add items to a wx.Menu have been modified
139 such that they return a reference to the wx.MenuItem that was created.
140 Additionally menu items and toolbar items have been modified to
141 automatically generate a new ID if -1 is given, similar to using -1
142 with window classess. This means that you can create menu or toolbar
143 items and event bindings without having to predefine a unique menu ID,
144 although you still can use IDs just like before if you want. For
145 example, these are all equivallent other than their specific ID
146 values::
147
148 1.
149 item = menu.Append(-1, "E&xit", "Terminate the App")
150 self.Bind(wx.EVT_MENU, self.OnExit, item)
151
152 2.
153 item = menu.Append(wx.ID_EXIT, "E&xit", "Terminate the App")
154 self.Bind(wx.EVT_MENU, self.OnExit, item)
155
156 3.
157 menu.Append(wx.ID_EXIT, "E&xit", "Terminate the App")
158 self.Bind(wx.EVT_MENU, self.OnExit, id=wx.ID_EXIT)
159
160
161 If you create your own custom event types and EVT_* functions, and you
162 want to be able to use them with the Bind method above then you should
163 change your EVT_* to be an instance of wx.PyEventBinder instead of a
164 function. For example, if you used to have something like this::
165
166 myCustomEventType = wxNewEventType()
167 def EVT_MY_CUSTOM_EVENT(win, id, func):
168 win.Connect(id, -1, myCustomEventType, func)
169
170
171 Change it like so::
172
173 myCustomEventType = wx.NewEventType()
174 EVT_MY_CUSTOM_EVENT = wx.PyEventBinder(myCustomEventType, 1)
175
176 The second parameter is an integer in [0, 1, 2] that specifies the
177 number of IDs that are needed to be passed to Connect.
178
179 **[Changed in 2.5.2.x]** There is also an Unbind method added to
180 wx.EvtHandler that can be used to disconenct event handlers. It looks
181 like this::
182
183 def Unbind(self, event, source=None, id=wx.ID_ANY, id2=wx.ID_ANY):
184 """
185 Disconencts the event handler binding for event from self.
186 Returns True if successful.
187 """
188
189
190
191
192 The wx Namespace
193 ----------------
194
195 The second phase of the wx Namespace Transition has begun. That means
196 that the real names of the classes and other symbols do not have the
197 'wx' prefix and the modules are located in a Python package named
198 wx. There is still a Python package named wxPython with modules
199 that have the names with the wx prefix for backwards compatibility.
200 Instead of dynamically changing the names at module load time like in
201 2.4, the compatibility modules are generated at build time and contain
202 assignment statements like this::
203
204 wxWindow = wx._core.Window
205
206 Don't let the "_core" in the name bother you. That and some other
207 modules are implementation details, and everything that was in the
208 wxPython.wx module before will still be in the wx package namespace
209 after this change. So from your code you would use it as wx.Window or
210 wxWindow if you import from the wxPython.wx module.
211
212 A few notes about how all of this was accomplished might be
213 interesting... SWIG is now run twice for each module that it is
214 generating code for. The first time it outputs an XML representaion
215 of the parse tree, which can be up to 20MB and 300K lines in size!
216 That XML is then run through a little Python script that creates a
217 file full of SWIG %rename directives that take the wx off of the
218 names, and also generates the Python compatibility file described
219 above that puts the wx back on the names. SWIG is then run a second
220 time to generate the C++ code to implement the extension module, and
221 uses the %rename directives that were generated in the first step.
222
223 Not every name is handled correctly (but the bulk of them are) and so
224 some work has to be done by hand, especially for the reverse-renamers.
225 So expect a few flaws here and there until everything gets sorted out.
226
227 In summary, the wx package and names without the "wx" prefix are now
228 the official form of the wxPython classes. For example::
229
230 import wx
231
232 class MyFrame(wx.Frame):
233 def __init__(self, parent, title):
234 wx.Frame.__init__(self, parent, -1, title)
235 p = wx.Panel(self, -1)
236 b = wx.Button(p, -1, "Do It", (10,10))
237 self.Bind(wx.EVT_BUTTON, self.JustDoIt, b)
238
239 def JustDoIt(self, evt):
240 print "It's done!"
241
242 app = wx.PySimpleApp()
243 f = MyFrame(None, "What's up?")
244 f.Show()
245 app.MainLoop()
246
247 You shouldn't need to migrate all your modules over to use the new
248 package and names right away as there are modules in place that try to
249 provide as much backwards compatibility of the names as possible. If
250 you rewrote the above sample using "from wxPython.wx import * ", the
251 old wxNames, and the old style of event binding it will still work
252 just fine.
253
254
255
256
257 New wx.DC Methods
258 -----------------
259
260 **[Changed in 2.5.2.x]** In wxPython 2.5.1.5 there was a new
261 implementation of the wx.DC Draw and other methods that broke
262 backwards compatibility in the name of consistency. That change has
263 been reverted and the wx.DC Draw methods with 2.4 compatible
264 signatures have been restored. In addition a new set of methods have
265 been added that take wx.Point and/or wx.Size parameters instead of
266 separate integer parameters. The Draw and etc. methods now available
267 in the wx.DC class are::
268
269
270 FloodFill(self, x, y, colour, style = wx.FLOOD_SURFACE)
271 FoodFillPoint(self, pt, colour, style = wx.FLOOD_SURFACE)
272
273 GetPixel(self, x,y)
274 GetPixelPoint(self, pt)
275
276 DrawLine(self, x1, y1, x2, y2)
277 DrawLinePoint(self, pt1, pt2)
278
279 CrossHair(self, x, y)
280 CrossHairPoint(self, pt)
281
282 DrawArc(self, x1, y1, x2, y2, xc, yc)
283 DrawArcPoint(self, pt1, pt2, centre)
284
285 DrawCheckMark(self, x, y, width, height)
286 DrawCheckMarkRect(self, rect)
287
288 DrawEllipticArc(self, x, y, w, h, sa, ea)
289 DrawEllipticArcPointSize(self, pt, sz, sa, ea)
290
291 DrawPoint(self, x, y)
292 DrawPointPoint(self, pt)
293
294 DrawRectangle(self, x, y, width, height)
295 DrawRectangleRect(self, rect)
296 DrawRectanglePointSize(self, pt, sz)
297
298 DrawRoundedRectangle(self, x, y, width, height, radius)
299 DrawRoundedRectangleRect(self, r, radius)
300 DrawRoundedRectanglePointSize(self, pt, sz, radius)
301
302 DrawCircle(self, x, y, radius)
303 DrawCirclePoint(self, pt, radius)
304
305 DrawEllipse(self, x, y, width, height)
306 DrawEllipseRect(self, rect)
307 DrawEllipsePointSize(self, pt, sz)
308
309 DrawIcon(self, icon, x, y)
310 DrawIconPoint(self, icon, pt)
311
312 DrawBitmap(self, bmp, x, y, useMask = False)
313 DrawBitmapPoint(self, bmp, pt, useMask = False)
314
315 DrawText(self, text, x, y)
316 DrawTextPoint(self, text, pt)
317
318 DrawRotatedText(self, text, x, y, angle)
319 DrawRotatedTextPoint(self, text, pt, angle)
320
321 bool Blit(self, xdest, ydest, width, height, sourceDC, xsrc, ysrc,
322 rop = wx.COPY, useMask = False, xsrcMask = -1, ysrcMask = -1)
323 BlitPointSize(self, destPt, sz, sourceDC, srcPt, rop = wx.COPY,
324 useMask = False, srcPtMask = wxDefaultPosition)
325
326
327 SetClippingRegion(self, x, y, width, height)
328 SetClippingRegionPointSize(self, pt, sz)
329 SetClippingRegionAsRegion(self, region)
330 SetClippingRect(self, rect)
331
332
333
334
335
336 Building, Extending and Embedding wxPython
337 ------------------------------------------
338
339 wxPython's setup.py script now expects to use existing libraries for
340 the contribs (gizmos, stc, xrc, etc.) rather than building local
341 copies of them. If you build your own copies of wxPython please be
342 aware that you now need to also build the ogl, stc, xrc, and gizmos
343 libraries in addition to the main wx lib.
344
345 The wxPython.h and other header files are now in
346 .../wxPython/include/wx/wxPython instead of in wxPython/src. You
347 should include it via the "wx/wxPython/wxPython.h" path and add
348 .../wxPython/include to your list of include paths. On OSX and
349 unix-like systems the wxPython headers are installed to the same place
350 that the wxWidgets headers are installed, so if you are building
351 wxPython compatible extensions on those platforms then your include
352 path should already be set properly.
353
354 If you are also using SWIG for your extension then you'll need to
355 adapt how the wxPython .i files are imported into your .i files. See
356 the wxPython sources for examples. Your modules will need to at least
357 ``%import core.i``, and possibly others if you need the definition of
358 other classes. Since you will need them to build your modules using
359 SWIG, the main wxPython .i files are also installed with the wxPython
360 headers in an i_files sibdirectory. It should be enough to pass a
361 -I/pathname on the command line for SWIG to find the files.
362
363 The bulk of wxPython's setup.py has been moved to another module,
364 wx/build/config.py. This module will be installed as part of wxPython
365 so 3rd party modules that wish to use the same setup/configuration
366 code can do so simply by importing this module from their own setup.py
367 scripts using ``import wx.build.config``.
368
369 You no longer need to call wxClassInfo::CleanUpClasses() and
370 wxClassInfo::InitializeClasses() in your extensions or when embedding
371 wxPython.
372
373 The usage of wxPyBeginAllowThreads and wxPyEndAllowThreads has changed
374 slightly. wxPyBeginAllowThreads now returns a boolean value that must
375 be passed to the coresponding wxPyEndAllowThreads function call. This
376 is to help do the RightThing when calls to these two functions are
377 nested, or if calls to external code in other extension modules that
378 are wrapped in the standard Py_(BEGIN|END)_ALLOW_THERADS may result in
379 wx event handlers being called (such as during the call to
380 os.startfile.)
381
382
383
384 Two (or Three!) Phase Create
385 ----------------------------
386
387 If you use the Precreate/Create method of instantiating a window, (for
388 example, to set an extended style flag, or for XRC handlers) then
389 there is now a new method named PostCreate to help with transplanting
390 the brain of the prewindow instance into the derived window instance.
391 For example::
392
393 class MyDialog(wx.Dialog):
394 def __init__(self, parent, ID, title, pos, size, style):
395 pre = wx.PreDialog()
396 pre.SetExtraStyle(wx.DIALOG_EX_CONTEXTHELP)
397 pre.Create(parent, ID, title, pos, size, style)
398 self.PostCreate(pre)
399
400
401
402 Sizers
403 ------
404
405 The hack allowing the old "option" keyword parameter has been removed.
406 If you use keyword args with w.xSizer Add, Insert, or Prepend methods
407 then you will need to use the ``proportion`` name instead of
408 ``option``. (The ``proportion`` keyword was also allowed in 2.4.2.4.)
409
410 When adding a spacer to a sizer you now need to use a wx.Size or a
411 2-integer sequence instead of separate width and height parameters.
412 This was optionally allowed in 2.4, but now it is required. This
413 allows for more consistency in how you add the various types of items
414 to a sizer. The first parameter defines the item (instead of the
415 possibily first two, depending on if you are doing a spacer or not,)
416 and that item can either be a window, a sizer or a spacer (which can
417 be a sequence or a wx.Size.) Removing the option for separate width
418 and height parameters greatly simplified the wrapper code.
419
420 The wx.GridBagSizer class (very similar to the RowColSizer in the
421 library) has been added to C++ and wrapped for wxPython. It can also
422 be used from XRC.
423
424 You should not use AddWindow, AddSizer, AddSpacer (and similar for
425 Insert, Prepend, and etc.) methods any longer. Just use Add and the
426 wrappers will figure out what to do. **[Changed in 2.5.2.x]**
427 AddWindow, AddSize, AddSpacer and etc. will now issue a
428 DeprecationWarning.
429
430 **[Changed in 2.5.2.x]** The Sizers have had some fundamental internal
431 changes in the 2.5.2.x release intended to make them do more of the
432 "Right Thing" but also be as backwards compatible as possible.
433 First a bit about how things used to work:
434
435 * The size that a window had when Add()ed to the sizer was assumed
436 to be its minimal size, and that size would always be used by
437 default when calculating layout size and positions, and the
438 sizer itself would keep track of that minimal size.
439
440 * If the window item was added with the ``wx.ADJUST_MINSIZE``
441 flag then when layout was calculated the item's ``GetBestSize``
442 would be used to reset the minimal size that the sizer used.
443
444 The main thrust of the new Sizer changes was to make behaviour like
445 ``wx.ADJUST_MINSIZE`` be the default, and also to push the tracking of
446 the minimal size to the window itself (since it knows its own needs)
447 instead of having the sizer take care of it. Consequently these
448 changes were made:
449
450 * The ``wx.FIXED_MINSIZE`` flag was added to allow for the old
451 behaviour. When this flag is used the size a window has when
452 added to the sizer will be treated as its minimal size and it
453 will not be readjusted on each layout.
454
455 * The min size stored in ``wx.Window`` and settable with
456 ``SetSizeHints`` or ``SetMinSize`` will by default be used by
457 the sizer (if it was set) as the minimal size of the sizer item.
458 If the min size was not set (or was only partially set) then the
459 window's best size is fetched and it is used instead of (or
460 blended with) the min size. ``wx.Window.GetBestFittingSize``
461 was added to facilitate getting the size to be used by the
462 sizers.
463
464 * The best size of a window is cached so it doesn't need to
465 recaculated on every layout. ``wx.Window.InvalidateBestSize``
466 was added and should be called (usually just internally in
467 control methods) whenever something is done that would make the
468 best size change.
469
470 * All wxControls were changed to set the minsize to what is passed
471 to the constructor or Create method, and also to set the real
472 size of the control to the blending of the min size and best
473 size. ``wx.Window.SetBestFittingSize`` was added to help with
474 this, although most controls don't need to call it directly
475 because it is called indirectly via the ``SetInitialSize``
476 called in the base classes.
477
478 At this time, the only situation known not to work the same as before
479 is the following::
480
481 win = SomeWidget(parent)
482 win.SetSize(SomeNonDefaultSize)
483 sizer.Add(win)
484
485 In this case the old code would have used the new size as the minimum,
486 but now the sizer will use the default size as the minimum rather than
487 the size set later. It is an easy fix though, just move the
488 specification of the size to the constructor (assuming that SomeWidget
489 will set its minsize there like the rest of the controls do) or call
490 ``SetMinSize`` instead of ``SetSize``.
491
492 In order to fit well with this new scheme of things, all wxControls or
493 custom controls should do the following things. (Depending on how
494 they are used you may also want to do the same thing for non-control
495 custom windows.)
496
497 * Either override or inherit a meaningful ``DoGetBestSize`` method
498 that calculates whatever size is "best" for the control. Once
499 that size is calculated then there should normally be a call to
500 ``CacheBestSize`` to save it for later use, unless for some
501 reason you want the best size to be recalculated on every
502 layout.
503
504 Note: In order to successfully override ``DoGetBestSize`` in
505 Python the class needs to be derived from ``wx.PyWindow``,
506 ``wx.PyControl``, or etc. If your class instead derives from
507 one of the standard wx classes then just be sure that the min
508 size gets explicitly set to what would have been the best size
509 and things should work properly in almost all situations.
510
511 * Any method that changes the attributes of the control such that
512 the best size will change should call ``InvalidateBestSize`` so
513 it will be recalculated the next time it is needed.
514
515 * The control's constructor and/or Create method should ensure
516 that the minsize is set to the size passed in, and that the
517 control is sized to a blending of the min size and best size.
518 This can be done by calling ``SetBestFittingSize``.
519
520
521
522 PlatformInfo
523 ------------
524
525 Added wx.PlatformInfo which is a tuple containing strings that
526 describe the platform and build options of wxPython. This lets you
527 know more about the build than just the __WXPORT__ value that
528 wx.Platform contains, such as if it is a GTK2 build. For example,
529 instead of::
530
531 if wx.Platform == "__WXGTK__":
532 ...
533
534 you should do this::
535
536 if "__WXGTK__" in wx.PlatformInfo:
537 ...
538
539 and you can specifically check for a wxGTK2 build by looking for
540 "gtk2" in wx.PlatformInfo. Unicode builds are also detectable this
541 way. If there are any other platform/toolkit/build flags that make
542 sense to add to this tuple please let me know.
543
544 BTW, wx.Platform will probably be deprecated in the future.
545
546
547
548 ActiveX
549 -------
550
551 Lindsay Mathieson's newest wxActiveX_ class has been wrapped into a new
552 extension module called wx.activex. It is very generic and dynamic
553 and should allow hosting of arbitray ActiveX controls within your
554 wxPython apps. So far I've tested it with IE, PDF, and Flash
555 controls, (and there are new samples in the demo and also library
556 modules supporting these.)
557
558 .. _wxActiveX: http://members.optusnet.com.au/~blackpaw1/wxactivex.html
559
560 The new wx.activex module contains a bunch of code, but the most
561 important things to look at are ActiveXWindow and ActiveXEvent.
562 ActiveXWindow derives from wxWindow and the constructor accepts a
563 CLSID for the ActiveX Control that should be created. (There is also
564 a CLSID class that can convert from a progID or a CLSID String.) The
565 ActiveXWindow class simply adds methods that allow you to query some
566 of the TypeInfo exposed by the ActiveX object, and also to get/set
567 properties or call methods by name. The Python implementation
568 automatically handles converting parameters and return values to/from
569 the types expected by the ActiveX code as specified by the TypeInfo,
570 (just bool, integers, floating point, strings and None/Empty so far,
571 but more can be handled later.)
572
573 That's pretty much all there is to the class, as I mentioned before it
574 is very generic and dynamic. Very little is hard-coded and everything
575 that is done with the actual ActiveX control is done at runtime and
576 referenced by property or method name. Since Python is such a dynamic
577 language this is a very good match. I thought for a while about doing
578 some Python black-magic and making the specific methods/properties of
579 the actual ActiveX control "appear" at runtime, but then decided that
580 it would be better and more understandable to do it via subclassing.
581 So there is a utility class in wx.activex that given an existing
582 ActiveXWindow instance can generate a .py module containing a derived
583 class with real methods and properties that do the Right Thing to
584 reflect those calls to the real ActiveX control. There is also a
585 script/tool module named genaxmodule that given a CLSID or progID and
586 a class name, will generate the module for you. There are a few
587 examples of the output of this tool in the wx.lib package, see
588 iewin.py, pdfwin.py and flashwin.py.
589
590 Currently the genaxmodule tool will tweak some of the names it
591 generates, but this can be controled if you would like to do it
592 differently by deriving your own class from GernerateAXModule,
593 overriding some methods and then using this class from a tool like
594 genaxmodule. [TODO: make specifying a new class on genaxmodule's
595 command-line possible.] The current default behavior is that any
596 event names that start with "On" will have the "On" dropped, property
597 names are converted to all lower case, and if any name is a Python
598 keyword it will have an underscore appended to it. GernerateAXModule
599 does it's best when generating the code in the new module, but it can
600 only be as good as the TypeInfo data available from the ActiveX
601 control so sometimes some tweaking will be needed. For example, the
602 IE web browser control defines the Flags parameter of the Navigate2
603 method as required, but MSDN says it is optional.
604
605 It is intended that this new wx.activex module will replace both the
606 older version of Lindsay's code available in iewin.IEHtmlWindow, and
607 also the wx.lib.activexwraper module. Probably the biggest
608 differences you'll ecounter in migrating activexwrapper-based code
609 (besides events working better without causing deadlocks) is that
610 events are no longer caught by overriding methods in your derived
611 class. Instead ActiveXWindow uses the wx event system and you bind
612 handlers for the ActiveX events exactly the same way you do for any wx
613 event. There is just one extra step needed and that is creating an
614 event ID from the ActiveX event name, and if you use the genaxmodule
615 tool then this extra step will be handled for you there. For example,
616 for the StatusTextChange event in the IE web browser control, this
617 code is generated for you::
618
619 wxEVT_StatusTextChange = wx.activex.RegisterActiveXEvent('StatusTextChange')
620 EVT_StatusTextChange = wx.PyEventBinder(wxEVT_StatusTextChange, 1)
621
622 and you would use it in your code like this::
623
624 self.Bind(iewin.EVT_StatusTextChange, self.UpdateStatusText, self.ie)
625
626 When the event happens and your event handler function is called the
627 event properties from the ActiveX control (if any) are converted to
628 attributes of the event object passed to the handler. (Can you say
629 'event' any more times in a single sentence? ;-) ) For example the
630 StatusTextChange event will also send the text that should be put into
631 the status line as an event parameter named "Text" and you can access
632 it your handlers as an attribute of the event object like this::
633
634 def UpdateStatusText(self, evt):
635 self.SetStatusText(evt.Text)
636
637 Usually these event object attributes should be considered read-only,
638 but some will be defined by the TypeInfo as output parameters. In
639 those cases if you modify the event object's attribute then that value
640 will be returned to the ActiveX control. For example, to prevent a
641 new window from being opened by the IE web browser control you can do
642 this in the handler for the iewin.EVT_NewWindow2 event::
643
644 def OnNewWindow2(self, evt):
645 evt.Cancel = True
646
647 So how do you know what methods, events and properties that an ActiveX
648 control supports? There is a funciton in wx.activex named GetAXInfo
649 that returns a printable summary of the TypeInfo from the ActiveX
650 instance passed in. You can use this as an example of how to browse
651 the TypeInfo provided, and there is also a copy of this function's
652 output appended as a comment to the modules produced by the
653 genaxmodule tool. Beyond that you'll need to consult the docs
654 provided by the makers of the ActiveX control that you are using.
655
656
657
658
659 PNG Images
660 ----------
661
662 Prior to 2.5 the PNG image handler would convert all alpha channel
663 information to a mask when the image was loaded. Pixels that were
664 more than halfway transparent would be made fully transparent by the
665 mask and the rest would be made fully opaque.
666
667 In 2.5 the image handler has been updated to preserve the alpha
668 channel and will now only create a mask when all the pixels in the
669 image are either fully transparent or fully opaque. In addition, the
670 wx.DC.DrawBitmap and wx.DC.Blit methods are able to correctly blend
671 the pixels in the image with partially transparent alpha values.
672 (Currently only on MSW and Mac, if anybody knows how to do it for GTK
673 then please submit a patch!)
674
675 If you are using a PNG with an alpha channel but you need to have a
676 wx.Mask like you automatically got in 2.4 then you can do one of the
677 following:
678
679 * Edit the image and make all the partially transparent pixels be
680 fully transparent.
681
682 * Use a different image type.
683
684 * Set a mask based on colour after you load the image.
685
686
687
688 OGL is dead! LONG LIVE OGL!
689 ---------------------------
690
691 **[Changed in 2.5.2.x]**
692
693 The wx.ogl module has been deprecated in favor of the new Python port
694 of the OGL library located at wx.lib.ogl contributed by Pierre Hjälm.
695 This will hopefully greatly extend the life of OGL within wxPython by
696 making it more easily maintainable and less prone to getting rusty as
697 there seems to be less and less interest in maintaining the C++
698 version.
699
700 There are only a few known compatibility issues at this time. First
701 is the location of OGL. The deprecated version is located in the
702 wx.ogl module, and the new version is in the wx.lib.ogl package. So
703 this just means that to start using the new version you need to adjust
704 your imports. So if your code currently has something like this::
705
706 import wx
707 import wx.ogl as ogl
708
709 Then just change it to this::
710
711 import wx
712 import wx.lib.ogl as ogl
713
714 The other compatibility issue deals with removing a wart in the
715 original API that was necessary in order to allow overloaded methods
716 in derived classes to call the same method in the base class when
717 using the old SWIG. Instead dedaling with the wart you can now just
718 call the base class method like you woudl for any other Python class.
719 For example, if you had to do something like this previously::
720
721 class MyDividedShape(ogl.DividedShape):
722 ...
723 def OnSizingEndDragLeft(self, pt, x, y, keys, attch):
724 self.base_OnSizingEndDragLeft(pt, x, y, keys, attch)
725 ...
726
727 You will need to change it to be like this::
728
729 class MyDividedShape(ogl.DividedShape):
730 ...
731 def OnSizingEndDragLeft(self, pt, x, y, keys, attch):
732 ogl.DividedShape.OnSizingEndDragLeft(self, pt, x, y, keys, attch)
733 ...
734
735
736
737 Obsolete Modules
738 ----------------
739
740 Instead of over a dozen separate extension modules linked together
741 into a single extension module, the "core" module is now just a few
742 extensions that are linked independently, and then merged together
743 later into the main namespace via Python code.
744
745 Because of the above and also because of the way the new SWIG works,
746 the "internal" module names have changed, but you shouldn't have been
747 using them anyway so it shouldn't bother you. ;-) In case you were
748 erroneously using them in 2.4, here are the internal extension modules
749 no longer exist:
750
751 * clip_dnd
752 * cmndlgs
753 * controls
754 * controls2
755 * events
756 * filesys
757 * fonts
758 * frames
759 * gdi
760 * image
761 * mdi
762 * misc
763 * misc2
764 * printfw
765 * sizers
766 * stattool
767 * streams
768 * utils
769 * windows
770 * windows2
771 * windows3
772
773 They have been replaced by the following, but please remember that
774 these are just "implementation details" and you should really be using
775 the objects in these modules only via the wx or wxPython.wx packages:
776
777 * _core
778 * _gdi
779 * _windows
780 * _controls
781 * _misc
782
783
784 The help module no longer exists and the classes therein are now part
785 of the core module imported with wxPython.wx or the wx package.
786
787
788
789
790 Other Stuff
791 -----------
792
793 wxPyDefaultPosition and wxPyDefaultSize are gone. Use the
794 wxDefaultPosition and wxDefaultSize objects instead.
795
796 Similarly, the wxSystemSettings backwards compatibiility aliases for
797 GetSystemColour, GetSystemFont and GetSystemMetric have also gone into
798 the bit-bucket. Use GetColour, GetFont and GetMetric instead.
799
800 Use the Python True/False constants instead of the true, TRUE, false,
801 FALSE that used to be provided with wxPython.
802
803 Use None instead of the ancient and should have been removed a long
804 time ago wx.NULL alias.
805
806 wx.TreeCtrl.GetFirstChild no longer needs to be passed the cookie
807 variable as the 2nd parameter. It still returns it though, for use
808 with GetNextChild.
809
810 The wx.NO_FULL_REPAINT_ON_RESIZE style is now the default style for
811 all windows. The name still exists for compatibility, but it is set
812 to zero. If you want to disable the setting (so it matches the old
813 default) then you need to use the new wx.FULL_REPAINT_ON_RESIZE style
814 flag otherwise only the freshly exposed areas of the window will be
815 refreshed.
816
817 wxPyTypeCast has been removed. Since we've had the OOR (Original
818 Object Return) for a couple years now there should be no need to use
819 wxPyTypeCast at all.
820
821 If you use the old wxPython package and wxPython.wx namespace then
822 there are compatibility aliases for much of the above items.
823
824 The wxWave class has been renamed to wxSound, and now has a slightly
825 different API.
826
827 wx.TaskbarIcon works on wxGTK-based platforms (for some window
828 managers,) however you have to manage it a little bit more than you
829 did before. Basically, the app will treat it like a top-level frame
830 in that if the wx.TaskBarIcon still exists when all the frames are
831 closed then the app will still not exit. You need to ensure that the
832 wx.TaskBarIcon is destroyed when your last Frame is closed. For
833 wxPython apps it is usually enough if your main frame object holds the
834 only reference to the wx.TaskBarIcon, then when the frame is closed
835 Python reference counting takes care of the rest.
836
837 Before Python 2.3 it was possible to pass a floating point object as a
838 parameter to a function that expected an integer, and the
839 PyArg_ParseTuple family of functions would automatically convert to
840 integer by truncating the fractional portion of the number. With
841 Python 2.3 that behavior was deprecated and a deprecation warning is
842 raised when you pass a floating point value, (for example, calling
843 wx.DC.DrawLine with floats for the position and size,) and lots of
844 developers using wxPython had to scramble to change their code to call
845 int() before calling wxPython methods. Recent changes in SWIG have
846 moved the conversion out of PyArg_ParseTuple to custom code that SWIG
847 generates. Since the default conversion fragment was a little too
848 strict and didn't generate a very meaningful exception when it failed,
849 I decided to use a custom fragment instead, and it turned out that
850 it's very easy to allow floats to be converted again just like they
851 used to be. So, in a nutshell, any numeric type that can be
852 converted to an integer is now legal to be passed to SWIG wrapped
853 functions in wxPython for parameters that are expecting an integer.
854 If the object is not already an integer then it will be asked to
855 convert itself to one. A similar conversion fragment is in place for
856 parameters that expect floating point values.
857
858 **[Changed in 2.5.2.x]** The MaskedEditCtrl modules have been moved
859 to their own sub-package, wx.lib.masked. See the docstrings and demo
860 for changes in capabilities, usage, etc.
861
862 **[Changed in 2.5.2.x]** wx.MaskColour constructor has been deprecated
863 and will raise a DeprecationWarning if used. The main wx.Mask
864 constructor has been modified to be compatible with wx.MaskColour so
865 you should use it instead.
866
867 **[Changed in 2.5.2.x]** In wx.TextCtrls that have the
868 wx.TE_PROCESS_TAB style the TAB key will be treated like an ordinary
869 character and will not cause any tab traversal navigation at all. If
870 you use this style but would still like to have the normal tab
871 traversal take place then you should send your own
872 wx.NavigationKeyEvent from the wx.EVT_KEY_DOWN handler. There is a
873 new Navigate method in the wx.Window class to help send the event and
874 it is used something like this::
875
876 flags = wx.NavigationKeyEvent.IsForward
877 if event.ShiftDown():
878 flags = wx.NavigationKeyEvent.IsBackward
879 if event.ControlDown():
880 flags |= wx.NavigationKeyEvent.WinChange
881 self.Navigate(flags)
882
883