Re: [wxhaskell-devel] Property sheet

[Jeremy O'D. <jer...@gm...>]

Hi Dave,

Playing catch-up after the weekend...

Short answer - I think you have the correct places to put code.

On 30 July 2011 00:56, Dave Tapley <duk...@gm...> wrote:

> On 29 July 2011 21:49, Dave Tapley <duk...@gm...> wrote:
>
>> Hi Jeremy,
>>
>> Did you ever make a start wrapping wxPropertyGrid?
>> http://permalink.gmane.org/gmane.comp.lang.haskell.wxhaskell.general/1016
>>
>> I'm going to have a go now.
>>
>> Dave,
>>
>
> In my quest to understand how a class from wxWidgets is wrapped I took at
> look at wxSlider as it shares the same class hierarchy as wxPropertyGrid and
> 'slider' is a fairly distinct term.
>
> Searching for 'slider' in the wxHaskell code I extracted the following
> references to it.
> Does this look complete? If anyone could comment further on what function
> each part provides I'd be very grateful.
>
>
> # HAND-WRITTEN FILES #
>
> ./wx/src/Graphics/UI/WX/Controls.hs:
> Haskell impl
>

'High' level Haskell wrapper. You place constructors which are
property-aware here. In most respects this is straightforward except that
you need to work out what instances are appropriate to a PropertyGrid. You
may want to look at
http://wewantarock.wordpress.com/2010/01/11/custom-controls-in-wxhaskell-part-3/for
some more information about implementing Attribute instances.

./wxcore/src/eiffel/wx_defs.e:
> Eiffel alias for wxEVT_COMMAND_SLIDER_UPDATED as
> expEVT_COMMAND_SLIDER_UPDATED
>

An ugly piece of legacy from the days when wxcore was derived from an Eiffel
wrapping of wxWidgets. Event identifiers need to be defined here.
I *really* want to get rid of this file one day - it serves no purpose to
have an Eiffel file these days.


> ./wxcore/src/include/wxc.h:
> TClassDefExtend saying wxSlider95 and wxSliderMSW are wxSlider
>

This creates the correct type witnesses to map the class Hierarchy.


> ./wxcore/src/include/wxc_glue.h:
> Decl of int expEVT_COMMAND_SLIDER_UPDATED();
> TClassDefExtend saying wxSlider is a wxControl
> Decl of many wxSlider_ methods such as wxSlider_ClearSel
> Decl of wxXmlResource_GetSlider method
>

This is basically where you need to put the declarations for C++ method
wrappers.

> ./wxcore/src/haskell/Graphics/UI/WXCore/Layout.hs:
> This code is commented out
>

I don't think you would need to do anything here


> ./wxcore/src/haskell/Graphics/UI/WXCore/Events.hs:
> Exports sliderOnCommand, sliderGetOnCommand
> Def for sliderOnCommand which sends wxEVT_COMMAND_SLIDER_UPDATED and take
> an eventHandler
> Def for sliderGetOnCommand which returns the event handler
>

Your Haskell event handler code goes here. You need one function which
reacts to events, which accepts an event handler as a parameter and a
function which will fetch your event handler (you need this mostly in case
you want to hook a further event handler which doesn't kill the one already
present).


> ./wxcore/src/cpp/extra.cpp:
> ifdef wxUSE_SLIDER  wxT("SLIDER")
>

I'm not completely sure why this is required. I suspect it's not used any
more.


> ./wxcore/src/cpp/eljslider.cpp:
> EWXWEXPORT calls for all the wxSlider_ methods decl'd in wxc_glue.h
>

Implementations of the wrappers. The old eljXXX naming convention for these
files really isn't necessary any more. I'd suggest calling the
implementation 'propertysheet.cpp' or something like that.


> ./wxcore/src/cpp/eljrc.cpp:
> BUILD_XRCGETCTRL_FN(Slider) (constructs functions for geting control
> pointers out of window hierarchies created from XRC files. The functions
> themselves)
>

Correct.


>
> ./wxcore/src/cpp/defs.cpp:EWXWCONSTANTINT(wxEVT_COMMAND_SLIDER_UPDATED,wxEVT_COMMAND_SLIDER_UPDATED)
>

I'd forgotten about these. Another way of wrapping up event values as
functions. I don't tend to do this, and I don't think anyone has for
years...

./wxcore/src/cpp/eljevent.cpp:
> MAKE_EVENT_WRAPPER(EVT_COMMAND_SLIDER_UPDATED)
>

I tend to do this instead. It does exactly the same thing as the code in
defs.cppp.

# MISC FILES #
>
> ./wxcore/wxcore.cabal:
>     add src/cpp/eljslider.cpp to c-sources
>

Obvious...

./samples/test/XRCControls/XRCControls_Wx.hs:
>     test code for xrc
>

You should probably write one or more pieces of test code for your wrapped
control.

# GENERATED FILES #
>
> ./wxcore/src/haskell/Graphics/UI/WXCore/WxcClassesMZ.hs:
> File generated by wxDirect from ./wxcore/src/include/wxc.h:
> Export of (wxEVT_COMMAND_SLIDER_UPDATED :: EventId)
> Export of many slider functions such as sliderClearSel, these match the
> wxSlider_ methods decl'd in wxc_glue.h
> Export of xmlResourceGetSlider function decl'd in wxc_glue.h
> Definition for slider functions using FFI foreign import ccall
> Definition of wxEVT_COMMAND_SLIDER_UPDATED which imports the enum value
> Definition of xmlResourceGetSlider using FFI foreign import ccall
>
> ./wxcore/src/haskell/Graphics/UI/WXCore/WxcClassInfo.hs:
> File generated by wxDirect
> Export of classSlider, classSlider95, classSliderMSW
> Export of downcastSlider, downcastSlider95, downcastSliderMSW
> Definition classSlider functions which bind them to the their C++ class
> names using a classInfoFindClass function
> Definition of downcast functions using an objectCast function
>
> ./wxcore/src/haskell/Graphics/UI/WXCore/WxcClassTypes.hs:
> File generated by wxDirect from ./wxcore/src/include/wxc.h:
> Exports Slider, TSlider, CSlider, and 95 and MSW variants
> Definitions of these as data types, encapsulating the class hierarchy from
> C++ classes. TSlider is the inheritance type, CSlider is the abstract type.
>

All correct.

Hope this helps.

Jeremy