gcombobox: Widgets to allow selection from a vector of items
In gWidgets: gWidgets API for Building Toolkit-Independent, Interactive GUIs

Description Usage Arguments Details See Also Examples

A combobox allows selection of a value from a list of items using a popup menu. Additionally, the widget can combine a text entry widget for user input outside of the pre-set list of items. A combobox is useful for selection from a moderate size of items (2-30, say). For smaller sets of items, a radio button group is a possibility, for larger sets of items, a scrollable (and perhaps searchable) table may be preferred.

gcombobox(items, selected = 1, editable = FALSE, coerce.with=NULL, handler = NULL, 
    action = NULL, container = NULL, ..., toolkit = guiToolkit())

gdroplist(items, selected = 1, editable = FALSE, coerce.with=NULL, handler = NULL, 
    action = NULL, container = NULL, ..., toolkit = guiToolkit())

`items`	Vector of values to select from. This may also be a data frame, in which case the first column is the vector of values, the second (if present) indicates a stock icon to display with the item (not all toolkits), and the third (if present) will indicate a tooltip to display (not all toolkits).
`selected`	For gradio the initial selected value (as an index) For a drop list, the first selected value. Use 0 to leave blank
`editable`	A logical indicating if the user can add an entry to the list of available answers
`coerce.with`	Apply this function to selected value before returning
`handler`	Called when selection is changed
`action`	Passed to handler when called.
`container`	Optional container to attach widget to
`...`	Passed to `add` method of container
`toolkit`	Which GUI toolkit to use

The initial items can be a vector or a data frame. Not all tool kits do something with the extra columns in the data frame.

The svalue method returns the selected value by name. Assume the value is a character vector. Use the coerce.with argument to return a value of a different type. If the extra argument index=TRUE is specified, the index of the selected value is given.

The svalue<- method can be used to set the selected value. This is done my name or if the argument index=TRUE is given by index. The value can be a data frame, in which case the first column is used to match against the current items.

The "[" method refers to the vector defining the items.

The "[<-" method can be used to change the vector defining the items.

The "length" method returns the number of items.

For gcombobox the argument editable=TRUE adds a text-edit box where the user can type in a selection. By default this value is returned as a character by svalue. Use coerce.with to coerce this prior to returning.

A combobox is one of several ways to select a value of a set of items. See also gcheckbox, gradio, gcheckboxgroup, and gtable.

Methods for gComponent objects are detailed in gWidgets-methods.

Event Handlers are detailed in gWidgets-handlers.

## Not run: 
  flavors <- c("vanilla", "chocolate", "strawberry")

  f <- function(h,...) print(
      paste("Yum",
      paste(svalue(h$obj),collapse=" and "),
      sep = " "))

  w <- gwindow("combobox example")
  gp <- ggroup(container=w)
  glabel("Favorite flavor:", container=gp)
  cb <- gcombobox(flavors, editable=TRUE, container=gp, handler=f)

  svalue(cb) <- "vanilla"
  svalue(cb)
  cbg[3] <- "raspberry"


## End(Not run)