# Create a GUI Window Create a GUI window with widgets using instructions from a Window Description File (aka mark-up file) . ```r createWin( fname, astext=FALSE, env=NULL ) ``` ## Arguments - `fname`: name of **window description file** or list returned from `parseWinFile`. - `astext`: logical: if `TRUE`, interpret `fname` as a vector of strings with each element representing a line in a **window description file**. - `env`: an environment in which to evaluate widget callback functions; see example. ## Details Generally, the markup file contains a single widget per line. However, widgets can span multiple lines by including a backslash ('\') character at the end of a line, prompting the suppression of the newline character. For more details on widget types and markup file, see PBSModelling-UG.pdf in the R directory `.../library/PBSmodelling/doc`. It is possible to use a Window Description List produced by `compileDescription` rather than a file name for `fname`. Another alternative is to pass a vector of characters to `fname` and set `astext=T`. This vector represents the file contents where each element is equivalent to a new line in the **window description file**. ## Author(s) Alex Couture-Beil, Vancouver Island University, Nanaimo BC ## Note Microsoft Windows users may experience difficulties switching focus between the R console and GUI windows. The latter frequently disappear from the screen and need to be reselected (either clicking on the task bar or pressing . This issue can be resolved by switching from MDI to SDI mode. From the R console menu bar, select and , then change the value of single or multiple windows to SDI. ## See Also `parseWinFile`, `getWinVal`, `setWinVal` `closeWin`, `compileDescription`, `createVector` `initHistory` for an example of using `astext=TRUE` `environment` ## Examples ```r ## Not run: # See file .../library/PBSmodelling/testWidgets/LissWin.txt # Calculate and draw the Lissajous figure local(envir=.PBSmodEnv,expr={ drawLiss <- function() { oldpar = par(no.readonly=TRUE); on.exit(par(oldpar)) getWinVal(scope="L"); ti=2*pi*(0:k)/k; x=sin(2*pi*m*ti); y=sin(2*pi*(n*ti+phi)); plot(x,y,type=ptype); invisible(NULL); }; createWin(system.file("testWidgets/LissWin.txt",package="PBSmodelling")); }) ############################################################ # Environment example: # function in global local(envir=.PBSmodEnv,expr={ hello <- function() { stop( "I shouldn't be called" ) } newNameGreeter <- function( name ) { # method to display window greet <- function() { createWin(c("button \"Say hello\" func=hello"), astext=TRUE, env=parent.env(environment())) } # hello method will refer to the name in this local scope hello <- function() { cat( "Hello", name, "\n" ) } # return functions which the user can call directly return( list( greet=greet, hello=hello ) ) } alex <- newNameGreeter( "Alex" ) jon <- newNameGreeter( "Jon" ) alex$hello() # prints hello Alex jon$hello() # prints hello Jon alex$greet() # creates a GUI with a button, which will print "hello Alex" when pushed }) ## End(Not run) ```

createWin function