grid.edit                package: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)

     grid.gedit(..., grep = TRUE, global = 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 specifies 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). 

  global: A boolean indicating whether the function should affect just
          the first match of the 'gPath', or whether all matches should
          be affected. 

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.

     'grid.gedit' ('g' for global) is just a convenience wrapper for
     'grid.edit' with different defaults.

Value:

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

Author(s):

     Paul Murrell

See Also:

     'grob', 'getGrob', 'addGrob', 'removeGrob'.

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")))

