rp.combo {rpanel}

R Documentation

A ‘combo’ for a panel

Description

This function adds a ‘combobox’ to the panel. When an item is pressed, a variable is set and an action function is called.

Usage

rp.combo(panel, variable, prompt=NULL, vals, initval=vals[1], pos=NULL, action=I,
  foreground=NULL, background=NULL, font=NULL, editable=FALSE,
  parentname=deparse(substitute(panel)), name=paste("combo", .nc(), sep=""), ...) 

Arguments

panel	the panel in which the combobox should appear.
variable	the name of the variable whose value is set by the combobox.
prompt	the label for the combobox.
vals	the values of variable used by the combo.
initval	the initial value of variable (optional). The initial value can also be specified in the call to rp.control.
pos	the layout instructions. Please see the rp.pos example and help for full details.
action	the function which is called when an item is chosen.
foreground	colour of the text
background	colour of the text background
font	font to be used
editable	whether the combobox can be edited or not.
parentname	this specifies the widget inside which the combobox should appear.
name	name assigned to the combobox, used for disposing of the widget
...	...

Details

The function action should take one argument, which should be the panel to which the combobox is attached.

See rp.grid for details of the grid layout system.

Value

If the parameter panel is the panelname string the same string is returned. If the panel object is used the altered panel is assigned to both the calling level and panel's environment level.

Warning

The action function should return the panel. Without this assignment any widgets added or alterations made to panel parameters within the action function will be lost.

Note

Parameters parent and ... have been discontinued in version 1.1. Note that the argument previously named var has been renamed variable to avoid reserved word issues.

References

rpanel: Simple interactive controls for R functions using the tcltk package. Journal of Statistical Software, 17, issue 9.

See Also

rp.checkbox,rp.control

Examples

## Not run: 
   callback <- function(panel) {
      print(panel$option)
      panel
   }
   panel <- rp.control()
   rp.combo(panel, option, "Pick an option:", 
            c("Option1","Option2","Other options"), action=callback)

## End(Not run)

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