Okay, I've attached a screenshot from Interface Builder to
better illustrate things. In the picture are two bars.
The top bar is of bar button items. With bar button items, we
can set the text, OR a premade image, OR an image, and one of three
styles: Bordered, Done, and Plain. Font is unchangeable. Text color
is unchangeable. Background color is unchangeable, as it's based on
the owning bar's color in the case of Bordered, and is always blue
in the case of Done.
Unrelated, but while I was researching this, I noticed a new
premade button, of page curl, added as of 4.0, that we might want
to introduce. It ignores the style property.
The bottom bar is of buttons added to the bar. This is a
different layout, and one we use when we have backgroundImage, etc.
The first button is a rounded rectangle, no background color. The
second is with the background color. Note that this background
color is put behind the rounded rectangle, not in it. The third is
a custom button, with no rounded rectangle, but as you can see, the
background color is just an ugly rectangle.
Finally, I made a custom button with text font, text color,
Shadow, shadow color, and shows-touch changed to resemble the bar
button item. However, this is a simulation. Worse yet, this is
probably incompatible with the bordered and done styles.
Bouncing back to Nolan for better clarification of what's
desired from what we can do.