rk.assign.preview.data {rkward}R Documentation

Manage (shortly) persistent data for previews (for use in RKWard plugins wishing to provide custom previews)

Description

rk.assign.preview.data stores data associated with a specific "id". Usually this id is provided by the <preview>-feature of a plugin. rk.get.preview.data retrieves data previously stored with rk.assign.preview.data rk.discard.preview.data discards data previously stored with rk.assign.preview.data. This gets called by the <preview>-box of the plugin, automtically, when the plugin dialog is closed. You do not generally have to call it manually. See the notes for running custom clearnup code, below.

Usage

rk.assign.preview.data(id, value = list())

rk.get.preview.data(id)

rk.discard.preview.data(id)

Arguments

id

(character). Id associated with the data. Usually this will be the 'id' value of the <preview>-box.

value.

The value to assign. If this is a list, and contains a function named "on.delete", this function will be run by rk.discard.preview.data (with the id as argument. This is useful for running custom clearnup code, such as removing temporary files, etc.

Value

rk.assign.preview.data amd rk.get.preview.data returns the preview data (newly) associated with the given id. rk.discard.preview.data returns NULL, invisibly.

Note: Plugins that want to produce a single plot, or open a single object via rk.edit() do not have to call these functions, manually. See the chapter on providing previews in the Introduction to writing plugins for RKWard.

Author(s)

Thomas Friedrichsmeier rkward-devel@kde.org

Examples

## To be generated in the preview() code section of a plugin

## NOT RUN
pdata &lt;- rk.get.preview.data("SOMEID")
if (is.null (pdata)) {
  outfile &lt;- rk.get.tempfile.name(prefix="preview", extension=".txt")
  pdata &lt;- list(filename=outfile, on.delete=function (id) {
    unlink(rk.get.preview.data(id)$filename)
  })
  rk.assign.preview.data("SOMEID", pdata)
}
try ({
  cat ("This is a test", pdata$filename)
  rk.edit.files(file=pdata$filename)
})
## END NOT RUN
[Package rkward version 0.6.5 Index]