Re: [boost] Java style GUI in C++

From: John Torjo (john.lists_at_[hidden])
Date: 2004-08-19 01:16:37

> Then engineer the library on top of that. This would simplify x-platform 
> development... the problem is working out the right abstraction.

Exactly! But is there any ;) ?
One interesting point is: in Windows, once you create a window on a 
thread, you'll only receive messages in that thread. I have no idea how 
this happens on Mac/Unix.

>>
>> I like the idea of layout managers. Still, it seems (to me) in 
>> real-life they kind of fail. You'll always want that special case 
>> where you need to hide control X and show control Y, etc.
> 
> 
> So why not have that ability in the framework? That is the reason I 
> posted this, to get ideas. It should not be that difficult to be able to 
> change the layouts at run-time... once the layout managers have been 
> written, that is.
> 

I you create the right layout manager, definitely ;)

> 
>>> [3] The support for events via "listeners". This will most likely be 
>>> geared towards key/mouse events and "action" events (e.g. when the 
>>> user presses on a button).
>>
>>
>> I'm not a big fan of listeners. You need to do a lot of coding 
>> manually to set them, etc. I've implemented them totally different - 
>> using event handler classes.
> 
> 
> My idea was something along the lines of:
> 
> class MouseEvent
> {
>   public:
>      static const int                 LeftButton   = 0;
>      static const int                 MiddleButton = 1;
>      static const int                 RightButton  = 2;
>   private:
>      int                              button;
>      unsigned int                     vkeys;
>      win::api::point                  pt;
>   public:
>      inline                 MouseEvent( int, WPARAM, LPARAM );
> };
> 
> MouseEvent::MouseEvent( int btn, WPARAM wp, LPARAM lp ):
>   button( btn ),
>   vkey(   wp ),
>   pt(     lp )
> {
> }
> 
> class MouseListener
> {
>   public:
>      virtual void                               mouseMove(              
> const MouseEvent & );
>      virtual void                               mouseButtonDown(        
> const MouseEvent & );
>      virtual void                               mouseButtonUp(          
> const MouseEvent & );
>      virtual void                               mouseButtonDoubleClick( 
> const MouseEvent & );
>   public:
>      virtual               ~MouseButtonListener();
> };

Good luck. I'm not a big fan of this. Mostly, because there are just so 
many events out there. You'll need to create a certain class for each.
And what about custom events and such?

What about commands/ notifications (Win32 only)?
As a side-note, how are these implemented on Unix/MAC? Is there 
similarity between them and Win32?

>>
>> I'm all for it, but again, I think it's so much work...
> 
> 
> But it will be fun! :D
> 

Great! Just keep us posted!

Best,
John

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John Torjo
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