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History

paul 2b9bef5afa lcl: move TWSControl.DragStart to TWSCustomListBox.DragStart because of limitation of TWS classes git-svn-id: trunk@42631 -		2013-09-06 07:29:10 +00:00
..
README.txt
wsbuttons.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wscalendar.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wschecklst.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wscomctrls.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wscontrols.pp	lcl: move TWSControl.DragStart to TWSCustomListBox.DragStart because of limitation of TWS classes	2013-09-06 07:29:10 +00:00
wsdesigner.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wsdialogs.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wsextctrls.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wsextdlgs.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wsfactory.pas	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wsforms.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wsgrids.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wsimglist.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wslazdeviceapis.pas	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wslclclasses.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wsmenus.pp	Applies patch from bug #17519 to fix regression in WinCE menus	2013-07-13 05:12:09 +00:00
wspairsplitter.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wsproc.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wsreferences.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wsspin.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00
wsstdctrls.pp	lcl: move TWSControl.DragStart to TWSCustomListBox.DragStart because of limitation of TWS classes	2013-09-06 07:29:10 +00:00
wstoolwin.pp	Improve license headers in sources, part 1. Refer to details about license, not copyright. Remove jargon about lack of warranty, it is covered in license already.	2013-05-24 18:30:06 +00:00

README.txt

This directory contains all skeleton widget set 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 will 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 component class 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 overridden 
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 compile time 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