traitr (version 0.14)

choiceItem: Item for choosing one of several values

Description

Item for choosing one of several values

Usage

choiceItem(value = "", values = "", by_index = FALSE, multiple = FALSE, editable = FALSE, name, label = name, help = "", tooltip = "", attr, model, editor, editor_type = c("", "gradio", "gcombobox", "gtable", "gedit", "gcheckboxgroup"), ...)

Arguments

value

Default value for the model. This is specified by index (or indices if multiple=TRUE)

values

Values that one can select from. May be a data frame or vector. The editor depends on the size of this: small will be radio button or checkboxes; medium is combobox; large is a table. One can override the behaviour by passing in a value to editor_type.

by_index

Do we get and set the main value by index or by value?

multiple

Multiple selection is allowed? If so, then only checkboxes or table widget is used

editable

Can user edit value to be selected? If so, the combobox is used

name

Required name for object. Names should be unique within a group of items

label

Optional label, default value is the name

help

Optional help string

tooltip

Optional tooltip to display

attr

A list of attributes to pass to widget on construction. Eg. attr=list(size=c(100,200)). The expand=TRUE value is a default for this.

model

Optional model. Useful if one wishes to use same model for multiple views

editor

Specification of editor (a view) to override default

editor_type

overide choice of editor by heuristic based on the number of possible values. Must set attr to match desired.

...

Passed to parent proto object during call to proto

Value

A proto object. Call obj$show_help() to view its methods and properties.

See Also

Item

Examples

## default is to get/set by value
         a <- choiceItem("a", letters, name="x")
         a$get_x()
         a$set_x("b")
         a$get_x()
## or by index, which can be easier to do
         b <- choiceItem("a", letters, name="x", by_index=TRUE)
         b$get_x()
         b$set_x(2)
         b$get_x()
## Size determines widget, unless you set editor_type
## a radio group
         rg <- choiceItem("a", letters[1:3], name="x")
## a combobox
         cb <- choiceItem("a", letters[1:8], name="x")
## a table
         tb <- choiceItem("a", letters[1:26], name="x")
## adjust size of table widget
         tb <- choiceItem("a", letters[1:26], name="x", attr=list(size=c(width=300,height=400)))
## Multiple and size determines widget type
## smaller uses checkboxgroup
         cbg <- choiceItem("a", letters[1:5], multiple=TRUE)
## larger uses table
         tbl <- choiceItem("a", letters[1:15], multiple=TRUE)
## place values in data frame to avoid generic header
         tbl <- choiceItem("a", data.frame("Column header"=letters[1:15]), multiple=TRUE)