============================
This document will help explain some of the major changes in wxPython
-2.5 and let you know what you need to do to adapt your programs to
-those changes. Be sure to also check in the CHANGES_ file like
-usual to see info about the not so major changes and other things that
-have been added to wxPython.
+2.5 since the 2.4 series and let you know what you need to do to adapt
+your programs to those changes. Be sure to also check in the CHANGES_
+file like usual to see info about the not so major changes and other
+things that have been added to wxPython.
.. _CHANGES: CHANGES.html
.. _here: http://www.wxwidgets.org/name.htm
This won't really affect wxPython all that much, other than the fact
-that the wxwindows.org domain name will be changing to wxwidgets.org,
-so mail list, CVS, and etc. addresses will be changing. We're going
+that the wxwindows.org domain name has changed to wxwidgets.org,
+so mail list, CVS, and etc. addresses have also changed. We're going
to try and smooth the transition as much as possible, but I wanted you
all to be aware of this change if you run into any issues.
operation unless you first have created an app object, (even on
Windows where most anything was possible before.)
+**[Changed in 2.5.2.x]** All the Window and GDI (pen, bitmap, etc.)
+class constructors and also many toplevel functions and static methods
+will now check that a wx.App object has already been created and will
+raise a wx.PyNoAppError exception if not.
+
+
SWIG 1.3
The second parameter is an integer in [0, 1, 2] that specifies the
number of IDs that are needed to be passed to Connect.
-**[Changed in 2.5.2.0]** There is also an Unbind method added to
+**[Changed in 2.5.2.x]** There is also an Unbind method added to
wx.EvtHandler that can be used to disconenct event handlers. It looks
like this::
New wx.DC Methods
-----------------
-**[Changed in 2.5.2.0]** In wxPython 2.5.1.5 there was a new
+**[Changed in 2.5.2.x]** In wxPython 2.5.1.5 there was a new
implementation of the wx.DC Draw and other methods that broke
backwards compatibility in the name of consistency. That change has
been reverted and the wx.DC Draw methods with 2.4 compatible
You should not use AddWindow, AddSizer, AddSpacer (and similar for
Insert, Prepend, and etc.) methods any longer. Just use Add and the
-wrappers will figure out what to do. **[Changed in 2.5.2.0]**
-AddWindow, AddSize, AddSpacer and etc. will now issue a
+wrappers will figure out what to do. **[Changed in 2.5.2.x]**
+AddWindow, AddSizer, AddSpacer and etc. will now issue a
DeprecationWarning.
-**[Changed in 2.5.2.0]** wx.ADJUST_MINSIZE is now the default
-behaviour for window items in sizers. This means that the item's
-GetMinSize and/or GetBestSize will be called when calculating layout
-and the return value from that will be used for the minimum size used
-by the sizer. The wx.FIXED_MINSIZE flag was added that will cause the
-sizer to use the old behaviour in that it will *not* call the window's
-methods to determine the new best size, instead the minsize that the
-window had when added to the sizer (or the size the window was created
-with) will always be used.
-
-Related to the above, when controls and some other window types are
-created either the size passed to the constructor, or their "best
-size" if an explicit size was not passed in, is set as the window's
-minimal size. For non top-level windows that hasn't meant much in the
-past, but now the sizers are sensitive to the window's minimal size.
-The key point to understand here is that it is no longer the window's
-size it has when added to the sizer that matters, but its minimal
-size. So you might have some issues to iron out if you create a
-control without a size and then set its size to something before
-adding it to the sizer. Since it's minimal size is probably not the
-size you set then the sizer will appear to be misbehaving. The fix is
-to either set the size when calling the window's constructor, or to
-reset the min size by calling SetSizeHints. You can call SetSizeHints
-at anytime to change the minsize of a window, just call the sizer's
-Layout method to redistribute the controls as needed.
+**[Changed in 2.5.2.x]** The Sizers have had some fundamental internal
+changes in the 2.5.2.x release intended to make them do more of the
+"Right Thing" but also be as backwards compatible as possible.
+First a bit about how things used to work:
+
+ * The size that a window had when Add()ed to the sizer was assumed
+ to be its minimal size, and that size would always be used by
+ default when calculating layout size and positions, and the
+ sizer itself would keep track of that minimal size.
+
+ * If the window item was added with the ``wx.ADJUST_MINSIZE``
+ flag then when layout was calculated the item's ``GetBestSize``
+ would be used to reset the minimal size that the sizer used.
+
+The main thrust of the new Sizer changes was to make behaviour like
+``wx.ADJUST_MINSIZE`` be the default, and also to push the tracking of
+the minimal size to the window itself (since it knows its own needs)
+instead of having the sizer take care of it. Consequently these
+changes were made:
+
+ * The ``wx.FIXED_MINSIZE`` flag was added to allow for the old
+ behaviour. When this flag is used the size a window has when
+ added to the sizer will be treated as its minimal size and it
+ will not be readjusted on each layout.
+
+ * The min size stored in ``wx.Window`` and settable with
+ ``SetSizeHints`` or ``SetMinSize`` will by default be used by
+ the sizer (if it was set) as the minimal size of the sizer item.
+ If the min size was not set (or was only partially set) then the
+ window's best size is fetched and it is used instead of (or
+ blended with) the min size. ``wx.Window.GetBestFittingSize``
+ was added to facilitate getting the size to be used by the
+ sizers.
+
+ * The best size of a window is cached so it doesn't need to
+ recaculated on every layout. ``wx.Window.InvalidateBestSize``
+ was added and should be called (usually just internally in
+ control methods) whenever something is done that would make the
+ best size change.
+
+ * All wxControls were changed to set the minsize to what is passed
+ to the constructor or Create method, and also to set the real
+ size of the control to the blending of the min size and best
+ size. ``wx.Window.SetBestFittingSize`` was added to help with
+ this, although most controls don't need to call it directly
+ because it is called indirectly via the ``SetInitialSize``
+ called in the base classes.
+
+At this time, the only situation known not to work the same as before
+is the following::
+
+ win = SomeWidget(parent)
+ win.SetSize(SomeNonDefaultSize)
+ sizer.Add(win)
+
+In this case the old code would have used the new size as the minimum,
+but now the sizer will use the default size as the minimum rather than
+the size set later. It is an easy fix though, just move the
+specification of the size to the constructor (assuming that SomeWidget
+will set its minsize there like the rest of the controls do) or call
+``SetMinSize`` instead of ``SetSize``.
+
+In order to fit well with this new scheme of things, all wxControls or
+custom controls should do the following things. (Depending on how
+they are used you may also want to do the same thing for non-control
+custom windows.)
+
+ * Either override or inherit a meaningful ``DoGetBestSize`` method
+ that calculates whatever size is "best" for the control. Once
+ that size is calculated then there should normally be a call to
+ ``CacheBestSize`` to save it for later use, unless for some
+ reason you want the best size to be recalculated on every
+ layout.
+
+ Note: In order to successfully override ``DoGetBestSize`` in
+ Python the class needs to be derived from ``wx.PyWindow``,
+ ``wx.PyControl``, or etc. If your class instead derives from
+ one of the standard wx classes then just be sure that the min
+ size gets explicitly set to what would have been the best size
+ and things should work properly in almost all situations.
+
+ * Any method that changes the attributes of the control such that
+ the best size will change should call ``InvalidateBestSize`` so
+ it will be recalculated the next time it is needed.
+
+ * The control's constructor and/or Create method should ensure
+ that the minsize is set to the size passed in, and that the
+ control is sized to a blending of the min size and best size.
+ This can be done by calling ``SetBestFittingSize``.
+
+PNG Images
+----------
+
+Prior to 2.5 the PNG image handler would convert all alpha channel
+information to a mask when the image was loaded. Pixels that were
+more than halfway transparent would be made fully transparent by the
+mask and the rest would be made fully opaque.
+
+In 2.5 the image handler has been updated to preserve the alpha
+channel and will now only create a mask when all the pixels in the
+image are either fully transparent or fully opaque. In addition, the
+wx.DC.DrawBitmap and wx.DC.Blit methods are able to correctly blend
+the pixels in the image with partially transparent alpha values.
+(Currently only on MSW and Mac, if anybody knows how to do it for GTK
+then please submit a patch!)
+
+If you are using a PNG with an alpha channel but you need to have a
+wx.Mask like you automatically got in 2.4 then you can do one of the
+following:
+
+ * Edit the image and make all the partially transparent pixels be
+ fully transparent.
+
+ * Use a different image type.
+
+ * Set a mask based on colour after you load the image.
+
+
+
+OGL is dead! LONG LIVE OGL!
+---------------------------
+
+**[Changed in 2.5.2.x]**
+
+The wx.ogl module has been deprecated in favor of the new Python port
+of the OGL library located at wx.lib.ogl contributed by Pierre Hjälm.
+This will hopefully greatly extend the life of OGL within wxPython by
+making it more easily maintainable and less prone to getting rusty as
+there seems to be less and less interest in maintaining the C++
+version.
+
+There are only a few known compatibility issues at this time. First
+is that the ogl.DrawnShape has not been reimplemented yet. Next is the
+location of OGL. The deprecated version is located in the wx.ogl
+module, and the new version is in the wx.lib.ogl package. So this
+just means that to start using the new version you need to adjust your
+imports. So if your code currently has something like this::
+
+ import wx
+ import wx.ogl as ogl
+
+Then just change it to this::
+
+ import wx
+ import wx.lib.ogl as ogl
+
+The other compatibility issue deals with removing a wart in the
+original API that was necessary in order to allow overloaded methods
+in derived classes to call the same method in the base class when
+using the old SWIG. Instead dedaling with the wart you can now just
+call the base class method like you woudl for any other Python class.
+For example, if you had to do something like this previously::
+
+ class MyDividedShape(ogl.DividedShape):
+ ...
+ def OnSizingEndDragLeft(self, pt, x, y, keys, attch):
+ self.base_OnSizingEndDragLeft(pt, x, y, keys, attch)
+ ...
+
+You will need to change it to be like this::
+
+ class MyDividedShape(ogl.DividedShape):
+ ...
+ def OnSizingEndDragLeft(self, pt, x, y, keys, attch):
+ ogl.DividedShape.OnSizingEndDragLeft(self, pt, x, y, keys, attch)
+ ...
+
+
+
Obsolete Modules
----------------
convert itself to one. A similar conversion fragment is in place for
parameters that expect floating point values.
-**[Changed in 2.5.2.0]** The MaskedEditCtrl modules have been moved
+**[Changed in 2.5.2.x]** The MaskedEditCtrl modules have been moved
to their own sub-package, wx.lib.masked. See the docstrings and demo
for changes in capabilities, usage, etc.
-**[Changed in 2.5.2.0]** wx.MaskColour constructor has been deprecated
+**[Changed in 2.5.2.x]** wx.MaskColour constructor has been deprecated
and will raise a DeprecationWarning if used. The main wx.Mask
constructor has been modified to be compatible with wx.MaskColour so
you should use it instead.
+
+**[Changed in 2.5.2.x]** In wx.TextCtrls that have the
+wx.TE_PROCESS_TAB style the TAB key will be treated like an ordinary
+character and will not cause any tab traversal navigation at all. If
+you use this style but would still like to have the normal tab
+traversal take place then you should send your own
+wx.NavigationKeyEvent from the wx.EVT_KEY_DOWN handler. There is a
+new Navigate method in the wx.Window class to help send the event and
+it is used something like this::
+
+ flags = wx.NavigationKeyEvent.IsForward
+ if event.ShiftDown():
+ flags = wx.NavigationKeyEvent.IsBackward
+ if event.ControlDown():
+ flags |= wx.NavigationKeyEvent.WinChange
+ self.Navigate(flags)
+
+
projects / wxWidgets.git / blobdiff