gformlayout {gWidgets} | R Documentation |
This constructor takes a list that defines the layout of widgets
and pieces them together to create a form or dialog. It is
similar to ggenericwidget
but offers more flexibility
with the layout, but does not offer the automatic creation of
the widget using a functions formals
.
gformlayout(lst, container = NULL, ..., toolkit = guiToolkit())
lst |
A list that defines the layout of the containers. See the details section. |
container |
Optional parent container for the widget |
... |
Passed to add method of parent container when given |
toolkit |
Which GUI toolkit to use |
The list defining the layout has the following key named components:
svalue
or \[
name
argument. If given, then a handler is
added to the widget that controls whether this new
widget/container should be enabled.depends.on
is specified, this
function is consulted to see if the widget should be
enabled. This function has argument value
which is
the return value of svalue
on the named widget this
new one depends on. It should return a logical value
indicating if the new widget is to be enabled.depends.FUN
is given by
addHandlerChanged
, this allows on to specify a
different addHandler
method. See the example.
If the type is gnotebook
, then each child should have a
label
component.
The new constructor fieldset
allows the organization of
its children in a table. These children should not be other
containers. If the component label
is non-null, the table is
packed into a gframe
container. The default number of
columns is just 1, but specifying columns
in the list can
increase this. Children are packed in row by row when more than
one column is given.
The labels can be adjusted. The component label.pos
can
be "left" (the default) for a label to the left of the widget,
or "top" to have the label on top of the widget. When the
position if "left", then the label.just
component is
consulted for justification of the label. This can have a value
of "right" (the default), "center" or "left"
If a component label.font
is given, then this will be
applied to each label through the font
method of the
label.
The children are specified as a list. Each child should have a
type
component, a label
component and a
name
component. Other components are passed to the
specified constructor in type through do.call
.
The return object has a few methods defined for it.
The \[
method returns a list with named components storing
the objects created by the constructors. Subsetting is
allowed. No \[\[
method is given, instead the
drop=TRUE
argument can be used with a single index is
given to return the component and not the list containing the component.
The svalue
method is a convenience method that applies
the svalue
method to each component of the list returned
by \[
.
The names
method is a convenience method that gives the
names of the widgets store in the list returned by \[
.
The design of this borrows from the FormPanel and FormLayout constructors in the extjs.com library for javascript programming.
## Not run: ## layout a collection of widgets to generate a t.test tTest <- list(type = "ggroup", horizontal = FALSE, children = list( list(type="fieldset", columns = 2, label = "Variable(s)", label.pos = "top", label.font = c(weight="bold"), children = list( list(name = "x", label = "x", type = "gedit", text = ""), list(name = "y", label = "y", type = "gedit", text = "", depends.on = "x", depends.FUN = function(value) nchar(value) > 0, depends.signal = "addHandlerBlur" ) ) ), list(type = "fieldset", label = "Hypotheses", columns = 2, children = list( list(name = "mu", type = "gedit", label = "Ho: mu=", text = "0", coerce.with = as.numeric), list(name = "alternative", type="gcombobox", label = "HA: ", items = c("two.sided","less","greater") ) ) ), list(type = "fieldset", label = "two sample test", columns = 2, depends.on = "y", depends.FUN = function(value) nchar(value) > 0, depends.signal = "addHandlerBlur", children = list( list(name = "paired", label = "paired samples", type = "gcombobox", items = c(FALSE, TRUE) ), list(name = "var.equal", label = "assume equal var", type = "gcombobox", items = c(FALSE, TRUE) ) ) ), list(type = "fieldset", columns = 1, children = list( list(name = "conf.level", label = "confidence level", type = "gedit", text = "0.95", coerce.with = as.numeric) ) ) ) ) w <- gwindow("t.test") g <- ggroup(horizontal = FALSE, cont = w) fl <- gformlayout(tTest, cont = g, expand=TRUE) bg <- ggroup(cont = g) addSpring(bg) b <- gbutton("run t.test", cont = bg) addHandlerChanged(b, function(h,...) { out <- svalue(fl) out$x <- svalue(out$x) # turn text string into numbers via get() if(out$y == "") { out$y <- out$paired <- NULL } else { out$y <- svalue(out$y) } print(do.call("t.test",out)) }) ## End(Not run)