general question on widget colors

[jody <jody xha gmail com>]

HI
i've got some question on widget colors.

In the documentation there are several methods pertaining to a widget's colors:

modify_fg()
  "Sets the foreground color for a widget in a particular state."

modify_bg()
  "Sets the background color for a widget in a particular state."

modify_text()
  "Sets the text color for a widget in a particular state."

However, when applied to a Gtk::Label, for example,  they have no effect at all.
Applied to a Gtk::Button, only modify_bg seems to work.
For a Gtk::Entry, only modify_text() works as expected, whereas modify_bg() only
affects the border around the text area.

Is there a reason why these methods have different behaviour depending
on the particular widget type?
Is there some place in the documentation where the effect of these methods
is explained for the various widgets?

Using Pango-markup a labels's text color can be changed - but it is a bit
cumbersome when you have to change colors on a mopuse over, for example:
- get the label's text
- create a markup string containing the label's text
- setting the label's markup

For other widgets such as Gtk::Arrow there seems no possibility
(i wouldn't know what kind of pango-markup to use since this
widget has no text)

Thanks in advance
  Jody