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Subject: Re: [boost] [rfc] cppgui
From: Felipe Magno de Almeida (felipe.m.almeida_at_[hidden])
Date: 2009-07-01 15:51:37

On Wed, Jul 1, 2009 at 4:41 PM, Stewart, Robert<Robert.Stewart_at_[hidden]> wrote:
> Felipe Magno de Almeida wrote:


>> I've started with a layout system implementation.
> One layout mechanism that I've found very easy to use and easy enough to implement is a "spring tab" which I first saw in Borland's Sprint word processor eons ago.  (I realize I'm crossing domains, but I think the idea applies readily.)  The notion of a spring tab is that it exerts equal force on each side to separate things.
> Put a spring tab against the left side and a widget on its right and the widget is right aligned.  Reverse the two and the widget is left aligned.  Surround a widget with spring tabs to center it.

I liked. I wanted something like this for spacing. I kinda liked the
spring name. But I'm not sure spring tabs as-is are generic enough. I
wanted to create the minimum features required, and as generic (or
primitive) as possible, which could attend almost all people.

> If you juxtapose spring tabs, they act as though there is a zero space, invisible widget between them.  Thus, <ST><ST>widget<ST> puts the widget 2/3 of the way across the horizontal extent.

Why 2/3 if there's four widgets?

> Anyway, the idea is that they are relatively trivial widgets that can be assembled together quickly to get a reasonable arrangement that adapts as a window is resized.  Perhaps that's a tool to include in your library.

Probably. But I wanted something more generic. Maybe the proportion
can be assigned. Also vertical springs are needed. And I'm not sure I
want it to be a widget. It doesn't have most operations a window has.
It only occupies space. And what happens if two widgets are
side-by-side to a spring. Should it press both? Do we link springs
with widgets?
I see a window as having a depth dimension, should springs press work
on a layer, or all depths of a window?

> _____
> Rob Stewart                           robert.stewart_at_[hidden]
> Software Engineer, Core Software      using std::disclaimer;
> Susquehanna International Group, LLP


Thanks for your suggestion,

Felipe Magno de Almeida

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