[R] One application of Tcltk2

[Abelian]

Dear All
I utilize the Tcltk2 to develop a Gui for application.
In order to make my function more clearly, i use a
function ,tk2notebook, to build several notes for different
application. I have studied the example of this function. In the R-
help, it provided a example below.

tt2 <- tktoplevel()
nb <- tk2notebook(tt2, tabs = c("Test", "Button"))
tkpack(nb, fill = "both", expand = 1)
tb1 <- tk2notetab(nb, "Test")
lab <- tk2label(tb1, text = "Nothing here.")
tkpack(lab)
tb2 <- tk2notetab(nb, "Button")
but <- tk2button(tb2, text = "Click me", command = function()
tkdestroy(tt2))
tkgrid(but)
tk2notetab.select(nb, "Button")
tk2notetab.text(nb) # Text of the currently selected tab

However, i want to modify the font and cex.size of tabs.
Because the original setting is too small.
By the way, how can i change the color of frames in this function?
The defult is gray, but i want to be skyblue.
I hope someone can give me suggestion or give me some direction to
solve this problem.
Sincerely