gUpdateMessage-class {iSPlot}R Documentation

Class "gUpdateMessage": A class to represent an update message

Description

gUpdateMessage is a class to represent an update message. When one of the components in the model-view-controller paradigm needs to tell another component to be updated, an update message is created. For example, when the data changes, it needs to tell the views to be updated and thus, a gUpdateViewMessage object is created. Both gUpdateViewMessage and gUpdateDataMessage classes are inherited from gUpdateMessage. Although, gUpdateMessage is not a virtual class, currently no objects of class gUpdateMessage are created in package, iSPlot.

Objects from the Class

Objects can be created by calls of the form new("gUpdateMessage", ...).

Slots

type:
the type of update to be performed, will be a character string
mData:
the data needed to perform the update, will be a list

Extends

Class "gMessage", directly.

Methods

mData
Returns the mData slot
mData<-
Sets the mData slot
type
Returns the type slot
type<-
Sets the type slot

Author(s)

Elizabeth Whalen

See Also

gMessage-class, gUpdateViewMessage-class, gUpdateDataMessage-class

Examples

  if (interactive())
  {
    createControlWindow()
    # should load data through Open Data or Open File under the File menu
    data(USArrests)
    loadDFData(USArrests,"USArrests")
    # plotting the data should occur through Plot Data under the 
    # Display menu
    createView(type = "plotView", dataName = "USArrests", 
               plotType = "sPlotView", dfRows = 1:nrow(USArrests), 
               dfColumns = 1:2)    
    # should modify using the control window (by choosing the view mode and
    # then clicking on a plot)
    # by interacting with a plot when the view mode is color, these 
    # functions will be called automatically
    modify("USArrests", Rname=c("Massachusetts","Ohio"), 
           Cname=c("color","color"), data=c("red","green")) 
    # create an update view message and then dispatch it so the points
    # that have changed will be replot
    plMessage<-new("gUpdateViewMessage",type="modify",Rname=c("Massachusetts",
                   "Ohio"))
    handleMessage(plMessage,dataName="USArrests")

    # now see if the message is inherited from gMessage
    is(plMessage,"gUpdateMessage")
  }

[Package iSPlot version 1.0.3 Index]