R: Edit the Description of a Grid Graphical Object

grid.edit {grid}

R Documentation

Edit the Description of a Grid Graphical Object

Description

Changes the value of one of the slots of a grob and redraws the grob.

Usage

grid.edit(gPath, ..., strict=FALSE, grep=FALSE, global=FALSE,
          allDevices=FALSE, redraw=TRUE) 
editGrob(grob, gPath=NULL, ..., strict=FALSE, grep=FALSE, global=FALSE)

Arguments

grob

A grob object.

...

Zero or more named arguments specifying new slot values.

gPath

A gPath object. For grid.edit this specifyies a grob on the display list. For editGrob this specifies a descendant of the specified grob.

strict

A boolean indicating whether the gPath must be matched exactly.

grep

A boolean indicating whether the gPath should be treated as a regular expression. Values are recycled across elements of the gPath (e.g., c(TRUE, FALSE) means that every odd element of the gPath will be treated as a regular expression). NOT YET IMPLEMENTED.

global

A boolean indicating whether the function should affect just the first match of the gPath, or whether all matches should be affected. NOT YET IMPLEMENTED.

allDevices

A boolean indicating whether all open devices should be searched for matches, or just the current device. NOT YET IMPLEMENTED.

redraw

A logical value to indicate whether to redraw the grob.

Details

editGrob copies the specified grob and returns a modified grob.

grid.edit destructively modifies a grob on the display list. If redraw is TRUE it then redraws everything to reflect the change.

Both functions call editDetails to allow a grob to perform custom actions and validDetails to check that the modified grob is still coherent.

Value

editGrob returns a grob object; grid.edit returns NULL.

Author(s)

Paul Murrell

Examples

grid.newpage()
grid.xaxis(name="xa", vp=viewport(width=.5, height=.5))
grid.edit("xa", gp=gpar(col="red"))
# won't work because no ticks (at is NULL)
try(grid.edit(gPath("xa", "ticks"), gp=gpar(col="green")))
grid.edit("xa", at=1:4/5)
# Now it should work
try(grid.edit(gPath("xa", "ticks"), gp=gpar(col="green")))

[Package grid version 1.9.1 ]