ANN: wxExtMiniFrame 1.6

[Francesco Montorsi]

Hi all,
    I've just released the wxCode component wxExtMiniFrame 1.6. Here 
follows some info about it:


  wxExtMiniFrame component info
  -----------------------------

  Website: http://wxcode.sourceforge.net/components/extminiframe
  Version: 1.6
  Description:
  This component provides a wxMainFrame window which is able to handle 
one or more
  wxExtMiniframes. wxExtMiniFrame extends the wxWidgets' standard 
wxMiniFrame adding
  the following main features:

   1) the ability to be activated/deactivated when the main frame
      activation state changes (wxMSW only): that is, when the
      mainframe is active, then also all the wxExtMiniFrame(s) are
      always drawn as active.

   2) the ability to contain any type of children, and to use
      wxSizers to layout them; this allows the creation of
      "advanced toolbars" (e.g. like MSOffice's ones)

   3) the ability to draw any type of wxMiniButton in its caption
      area (some standard minibuttons are provided)

   4) the ability to be rolled/unrolled (maybe using the wxCollapseBox 
minibutton);
      useful to temporary make smaller big wxExtMiniFrame windows

   5) the ability to show a context menu, when right-clicked in the
      caption bar, to allow the user to show/hide a specific wxExtMiniFrame
      hold by the wxMainFrame

   6) the ability to save/load the layout of the wxExtMiniFrame(s)
      in the given wxConfig object

   7) the cross-platformness (wxMSW, wxX11 and wxGTK)



  wxExtMiniFrame sample
  ---------------------

  This is a little application (a modified version of the minimal sample 
taken from
  the wxWidgets library) that uses the wxExtMiniFrame class showing its 
features.

  For information about wxExtMiniFrame design, please read the sections 
below.




  Installation
  ------------

  When building on win32, you can use the makefiles in the BUILD folder.
  When building wxExtMiniFrame on Unix/Linux do:

   ./configure
   make
   make install

  Type "./configure --help" for more info.
  For any problem, feel free to contact frm at users.sourceforge.net


  ChangeLog
  ---------

  1.6

      - updated to the new bakefile build system,
      - revised code for compatibility with wxWidgets 2.8
      - fixed rendering of wxExtMiniFrame under wxGTK 2 (in particular like
        the ext miniframe title, the minibutton rendering, the XOR rectangle
        drawn when the miniframe is moved)


  DESIGN issues (that is, "How I wasted my time trying various approaches")
  -------------------------------------------------------------------------

  Another approach for the implementation of a window such as wxExtMiniFrame
  could be to derive a class from wxFrame and then, as I tried, to 
emulate the
  active state of the mainframe drawing a fake title bar over the real bar.
  This approach has two problems:
  1) under Win32 it generates some flickering, specially for big palettes
  2) under GTK it cannot be implemented because there's no way to draw the
     mainframe's titlebar as active when it is not
     (this is a more generic problem: X windowing system gives the control
      of the top level window appearance to the "Window managers"; the
      typical window managers are KDE, Gnome, Motif... the application have
      no control over the toplevel window appearance including their 
titlebars)

  Another first approach could also be to avoid accepting the focus on the
  palette window and, even while the user is dragging/resizing the window,
  continuosly transfer focus from the palette to the main frame: like the
  previous solution, in this way flickering would produce a very nasty
  effect... (at least on Win32 where I tried it)





  FOCUS issues on Win32
  ---------------------

  One of the major features of wxExtMiniFrame is its ability to keep
  always the same activation state of the wxMainFrame associated with
  an user-intuitive interface.

  I managed to implement this feature on Win32 only for one reason:
  on GTK we miss some important information (the window which is going
  to be activated, for example) for events such as activation & nonclient
  activation...

  This feature is much more difficult to achieve than it would seems
  because one fix rule of Win32 is that only one window at time can
  be the active window. There's no way to have two active windows
  at the same time... however, wxExtMiniFrame uses the same trick used
  by classes like CMiniFrameWnd in the MFC (that is, the classes used
  to create detachable toolbars): when the active window is the parent
  window, the wxExtMiniFrame draws itself with the color of an active
  caption even if it's not.

  The focus synchronization system must be able to handle the focus
  changes summed up in this table:

                  [0] = another app or a child of [1], which is not [2]
                  [1] = the wxMainFrame which owns [2]
                  [2] = a wxExtMiniFrame owned by [1]


   focus   |            what must be done            | the function which
   change  |                                         |       does it
  ---------+-----------------------------------------+-------------------
  [0]->[1] | [1] becomes ACTIVE;                     | wxMainFrame::
           | all wxExtMiniFrames must be ACTIVATED   |   OnActivate
           |                                         |
  [1]->[0] | [1] becomes INACTIVE;                   | wxMainFrame::
           | all wxExtMiniFrames must be DEACTIVATED |   OnActivate
           |                                         |
  [1]->[2] | [1] doesn't update its titlebar (that   | wxMainFrame::
           | is, it keeps its ACTIVE color);         |   MSWOnNcActivate
           |                                         |
  [2]->[1] | [1] should already be drawn as ACTIVE   | wxExtMiniFrame::
           | [2] must keep its ACTIVE color          |   OnActivate
           |                                         |
  [2]->[0] | [2] should notify [1] that it must be   | wxExtMiniFrame::
           | drawn as INACTIVE like all its palettes |   MSWOnActivate
           |                                         |
  [0]->[2] | [2] should notify [1] that it must be   | wxExtMiniFrame::
           | drawn as ACTIVE like all its palettes   |   MSWOnActivate



  Known bugs
  ----------

  -> under wxMSW, there is some flickering when minibuttons are redrawn
  -> under wxX11, there is some problem with wxConfig... this is a 
wxWidgets bug
  -> under wxGTK, there is a strange line of pixels drawn with wrong 
colour immediately
     under the minibuttons



  Authors' info
  -------------

  Francesco Montorsi          frm at users.sourceforge.net

  Thanks to Ajitha Pai <ajithapai at users.sourceforge.net> for the help.