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lazarus/lcl/widgetset
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mattias 2e08e62328 added ldocktree.pas 
git-svn-id: trunk@7311 -
2005-07-01 18:20:41 +00:00
..
README Modified WS class hierarchy on registration 2004-05-01 16:50:57 +00:00
wsactnlist.pp Modified WS class hierarchy on registration 2004-05-01 16:50:57 +00:00
wsarrow.pp convert LM_SETVALUE message to interface methods 2004-09-19 18:50:28 +00:00
wsbuttons.pp implement active default control switching 2005-04-17 18:41:15 +00:00
wscalendar.pp convert LM_SETVALUE message to interface methods 2004-09-19 18:50:28 +00:00
wschecklst.pp convert LM_SETBORDER message to interface method 2004-09-17 07:55:13 +00:00
wsclistbox.pp Modified WS class hierarchy on registration 2004-05-01 16:50:57 +00:00
wscomctrls.pp added ldocktree.pas 2005-07-01 18:20:41 +00:00
wscontrols.pp * first 64bit changes 2005-02-05 16:09:52 +00:00
wsdbctrls.pp swap TCustomStaticText and TCustomLabel 2005-01-07 20:51:11 +00:00
wsdbgrids.pp Modified WS class hierarchy on registration 2004-05-01 16:50:57 +00:00
wsdialogs.pp convert LM_CREATE message to interface methods 2004-09-24 21:34:14 +00:00
wsdirsel.pp Modified WS class hierarchy on registration 2004-05-01 16:50:57 +00:00
wseditbtn.pp Modified WS class hierarchy on registration 2004-05-01 16:50:57 +00:00
wsextctrls.pp move GetNotebookTabIndexAtPos to the widgetset interface 2005-03-31 21:29:45 +00:00
wsextdlgs.pp Modified WS class hierarchy on registration 2004-05-01 16:50:57 +00:00
wsfilectrl.pp Modified WS class hierarchy on registration 2004-05-01 16:50:57 +00:00
wsforms.pp implemented TCustomForm.ShowInTaskBar for gtk1+2 from Andrew Haines 2005-03-19 23:36:26 +00:00
wsgrids.pp Modified WS class hierarchy on registration 2004-05-01 16:50:57 +00:00
wsimglist.pp Modified WS class hierarchy on registration 2004-05-01 16:50:57 +00:00
wslclclasses.pp convert LM_CREATE message to interface methods 2004-09-24 21:34:14 +00:00
wsmaskedit.pp Modified WS class hierarchy on registration 2004-05-01 16:50:57 +00:00
wsmenus.pp moved some menu intf methods to the TXXXWSMenuItem class from Martin Smat 2005-07-01 12:07:50 +00:00
wspairsplitter.pp Modified WS class hierarchy on registration 2004-05-01 16:50:57 +00:00
wsproc.pp + Added WSBitBtn interface 2004-05-16 23:24:41 +00:00
wsspin.pp convert LM_SETPROPERTIES message to interface method for TCustomSpinEdit 2004-09-23 21:16:46 +00:00
wsstdctrls.pp accelerated TMemo on gtk, gtk2 and win32 interface from Andrew Haines 2005-04-05 19:41:19 +00:00
wstoolwin.pp Modified WS class hierarchy on registration 2004-05-01 16:50:57 +00:00

README 

This directory contains all sceleton widgetset component 
classes. These classes will never get instantiated and may 
only contain class functions.
  
=========  
IMPORTANT
=========  

Derivation and inheritance of classes is different then one
might be used to. It wil be explained by the following 
examples.

Suppose the following LCL class hierarchy:

 TLCLComponent
     |
  TControl
     |
 TWinControl
 
the corresponding WS skeleton would be

 TWSLCLComponent
      |
  TWSControl
      |
 TWSWinControl


When method X of TWSControl gets implemented by 
widgetset Q the hierarchy looks like

 TWSLCLComponent
      |
  TWSControl.X --> TQWSControl.X
      |
 TWSWinControl


Calling TWSWinControl.X doesn't call TQWSControl.X since
it's parent is TWSControl. This problem is solved by 
modifying the class hierarchy at runtime.
When a ComponentClass is registered by RegisterWSComponent,
the class is copied and the vmt entries are adjusted so 
that the hierarchy looks like:


 TWSLCLComponent
      |
  TWSControl.X --> TQWSControl.X
                        |
                   TWSWinControl

In this case, calling TWSWinControl.X will call the overriden 
TQWSControl.X. The only thing which doesn't get handled is the 
inherited statement. Suppose there is also a TQWSWinControl.X 
which implements a few extra steps. In a normal situation one 
would have called "inherited". The call to inherited is
resolved at compiletime and would in this example to a call to
TWSControl.X. That is not what we want.
To get around this, call the parent yourself:
  TWSWinControlClass(ClassParent).X