R: A constructor to create widgets for evaluating functions

ggenericwidget {gWidgets} | R Documentation

## A constructor to create widgets for evaluating functions

### Description

This constructor creates a widget for collecting arguments for a function using a list to define the widget's components. When called with a function name a list is created on the fly which can be used as is, or modified as desired.

### Usage

    ggenericwidget(lst,  cli = NULL, container = NULL, ..., toolkit = guiToolkit())

### Arguments

`lst` | Either a list defining the widget or a function name as a string. In the latter case, the defining list may be retrieved by the `svalue` method.

`x=` for initial variable name.

`cli` | An instance of `gcommandline` or NULL. If NULL, then a new command line pops up in its own window
`container` | Optional container to attach widget to

`...` | Currently ignored by `ggenericwidget`, but passed along to `gedit` by `geditlist` and `geditnamedlist`
`toolkit` | Which GUI toolkit to use

### Details

This widget provides an easy way to create dialogs that collect the arguments for a function evaluation. When the OK button is clicked, the arguments are collected and passed along to the function specified via the `action` part of the list. When collecting the arguments, empty strings are not passed along.

The easiest usage is to simply provide a function name and have `autogenerategeneric` take a stab. However, in the long run it might be better to use `autogenerategeneric` to create an initial list, and then modify this to adjust the widget's look.

The list contains several named components

title

  The title for the widget

help

  What help page is called

type

  Either "text" or "graphic." Currently ignored.

variableType

  Describes the type of variable. Either "univariate", "univariatetable","fileurl","bivariate", "model", "lattice", "lmer" or `NULL`. This value is passed directly to `gvariables`. For non-NULL values, the widget shows an appropriate area for collecting the main variable. For the model and lattice interfaces buttons allow editing of fields by subsequent dialogs.

variableTypeExtras

  An optional list with components `name` and `value` containing a name and value passed along to the constructor for the variable type. Useful to override default

assignto

  If TRUE, creates box for collecting name for assigning output

action

  a list with named components `beginning` and `ending`. The arguments are collected and pasted together to form a string containing the R command to execute. These get put at the beginning and end of the string. A typical pair would be something like "prop.test(" and ")".

arguments

  a list with named components. In the simplest usage the names are argument names, and the components are lists with entries that create the corresponding widget. The first such component is called `type` and is the name of a gWidget, such as `"gradio"`. Subsequent components are passed to this function using `do.call`.

  The constructors `geditlist` and `geditnamedlist` can be used when the input is to be a list of values or a list of named values.

  In the more complicated cases, these named components can be grouped into a list component. The name of this is then used to block the arguments. See the example.

The `svalue` method returns the value of the list. This can be used to retrieve the list that is created when the constructor is called with a function name.

### Note

This function may be improved and the list defining it changed.

### Examples

    ## Not run:
    	## a sample list definition
    ## Save some typing by defining a list to be used more than once later
    TRUE.list <- list(
      type = "gradio",
      items = c("TRUE","FALSE")
      )

    ## define a list for producing a histogram widget
    hist.list <- list(
      title = "hist()",
      help = "hist",
      action = list(
        beginning = "hist(",
        ending = ")"
        ),
      type = "graphic",                      # either text or graphic
      variableType = "univariate",           # single variable
      arguments = list(
        adjustments = list(
          breaks= list(
            type="gdroplist",
            items=c("\"Sturges\"","\"Scott\"","\"Friedman-Diaconis\"")
            ),
          probability = TRUE.list,
          include.lowest = TRUE.list,
          right = TRUE.list,
          shading = list(
            density = list(
                type="gedit",
                text=NULL
            ),
          angle = list(
            type="gedit",
            coerce.with="as.numeric",
            text="45"
            )
            )
          )
        )
      )

    ggenericwidget(hist.list, container=TRUE)
    ## or to autogenerate one
    ggenericwidget("boxplot.default", container=TRUE)

    ## End(Not run)

[Package gWidgets version 0.0-54 Index]