Re: grid widget (was Re: possible removal of GtkWrapBox)

[Tristan Van Berkom <tristanvb openismus com>]

On Sun, 2010-10-10 at 12:34 -0400, Havoc Pennington wrote:
> Hi,
> 
> On Sun, Oct 10, 2010 at 10:41 AM, Tristan Van Berkom
> <tristanvb openismus com> wrote:
> > I would only expect the expand to be distributed evenly among
> > children as, thats what GtkBox does ;-)
> 
> But the whole point of the exercise is to mop up GtkBox cruft...
> 
> > I'm not sure that having all the children stop expanding
> > when an expand child is added is any worse than having all
> > the extra column/row spacing suddenly disappear.
> 
> The general principle I think is that if a child doesn't say it can
> benefit from expand, it doesn't make sense to expand it. For example,
> expanding a button just looks bad.
> 
> > Maybe a similar spreading option would be useful for the Grid ?
> > (i.e. decide whether Grid children EXPAND, or line up at the START
> > or END, or get spread EVEN)...
> 
> You can use widget halign/valign to do START and END right? Then Grid
> never gets extra allocation.
> 
> The only case where Grid needs something "special" is if it does get
> extra allocation, i.e. it is align=FILL.
> In that case, if there are expand children, obviously extra allocation
> should go to them.
> 
> If there are no expand children, then the two choices are to allocate
> extra space evenly to the children, OR allocate extra space as spacing
> between the children.
> 
> Allocating extra space "around" the children is redundant with setting
> halign/valign on the grid so I think that is a pointless feature.
> 
> Allocating extra space evenly to the children I think is redundant
> with setting expand=true on the children.
> 
> So the only thing that can't be done already is to allocate extra
> spacing in between the children. You can then get any of the effects:
> 
> a) no expand=true children, grid align = FILL: extra allocation
> becomes spacing between children
> b) any expand=true children, grid align = FILL: extra allocation goes
> to the expand=true children only
> c) no expand=true children, grid align = START | CENTER | END: extra
> allocation is spacing on one side or both sides of grid
> 
> If it works like GtkBox, then in case a) you just pretend it is case
> b) with all children set to expand=true. This means:
>  - there's no way to do a) anymore unless you add some special option
>  - the behavior is illogical (widgets with expand=false expand anyway,
> until you set one to expand=true then they don't?)
> 
> The simple obvious thing is: children expand only if they are expand=true.
> 

To be clear, I have no objection either way; and it's true that adding
spacing between children gives us something not already achieved by
the align properties.



> Havoc