lazarus

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History

paul f83756a0d3 - request combobox item heights through onMeasureItem when style is ownerdraw variable + misc bugs with ItemHeight (report 0008113) git-svn-id: trunk@11070 -		2007-05-04 01:26:23 +00:00
..
README.txt	fixed typos from Darius	2006-10-23 10:14:31 +00:00
wsactnlist.pp
wsarrow.pp	added class keyword to proc bodies for fpc 2.1.1	2006-05-27 17:40:59 +00:00
wsbuttons.pp	Carbon intf.: improved TSpeedButton look	2007-05-03 12:52:33 +00:00
wscalendar.pp	added class keyword to proc bodies for fpc 2.1.1	2006-05-27 17:40:59 +00:00
wschecklst.pp	added class keyword to proc bodies for fpc 2.1.1	2006-05-27 17:40:59 +00:00
wsclistbox.pp
wscomctrls.pp	declared TListItem.Position, TListItem.Top, TListItem.Left with implementation for win32 (0008426)	2007-04-18 15:51:50 +00:00
wscontrols.pp	- some minor changes and comments for native win32 image list	2007-04-11 05:41:56 +00:00
wsdbctrls.pp
wsdbgrids.pp
wsdialogs.pp	lcl wsdialogs: use LCLType to have a 64 bits THandle on 64 bits cpus from Giulio Bernardi	2006-11-26 19:19:22 +00:00
wsdirsel.pp
wseditbtn.pp
wsextctrls.pp	added class keyword to proc bodies for fpc 2.1.1	2006-05-27 17:40:59 +00:00
wsextdlgs.pp
wsfilectrl.pp
wsforms.pp	added class keyword to proc bodies for fpc 2.1.1	2006-05-27 17:40:59 +00:00
wsgrids.pp
wsimglist.pp	* Native imagelists - part 3 add&remove	2007-04-09 23:17:44 +00:00
wslclclasses.pp	- TLCLHandleComponent modified: added 2 virtual methods: WSCreateHandle and WSDestroyHandle	2007-04-09 07:03:40 +00:00
wsmaskedit.pp
wsmenus.pp	added class keyword to proc bodies for fpc 2.1.1	2006-05-27 17:40:59 +00:00
wspairsplitter.pp	* patch for tpairsplitter by Paul Ishenin	2007-03-06 00:08:35 +00:00
wsproc.pp	* Native imagelists - part 3 add&remove	2007-04-09 23:17:44 +00:00
wsspin.pp	added class keyword to proc bodies for fpc 2.1.1	2006-05-27 17:40:59 +00:00
wsstdctrls.pp	- request combobox item heights through onMeasureItem when style is ownerdraw variable + misc bugs with ItemHeight (report 0008113)	2007-05-04 01:26:23 +00:00
wstoolwin.pp

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