RwxWidgets Annotated Examples

Drag and Drop XML, HTML,PDF

The basics of drag and drop and an more involved, dynamic example in which we determine the suitablility of a drop target based on the content and not the type of the data being dragged. This also shows how we can implement a derived C++ class with R functions as methods.

Menu XML, HTML,PDF

An example of creating a wxMenuBar with different menus and and cascading menus within those. This also illustrates how to handle events on menus and for collections of menu items using a range of widget ids.

Extended C++ classes with R methods XML, HTML,PDF

This illustrates how we can create instances of derived C++ classes and implement its methods with R functions. The example uses the wxDir class and the wxDirTraverser interface in C++ for working with files and directories.

A basic wxTreeCtrl example XML, HTML,PDF

This illustrates how to do basic things with the wxTreeCtrl class and the associated wxTreeItemId objects. We change the background and foreground colors and and set images on some of the items.

Displaying an XML document with a wxTreeCtrl widget XML, HTML,PDF

This displays the nodes of an XML tree in a wxTreeCtrl.

Working with wxImageList XML, HTML,PDF

This shows how to create images/bitmaps in R using wxWidgets and managing these in a wxImageList which can be used in widgets such as wxNotebook, wxTreeCtrl, wxListCtrl, etc.

Adding widgets to a wxDialog XML, HTML,PDF

Building a wxDialog from scratch. XML, HTML,PDF

Hiding/Showing widgets within a wxSizer XML, HTML,PDF

We write these documents using an XML format that allows us to combine the annotation with the code and read them in various formats. We use the Docbook format for marking up the text and inserting the code and use XML and XSL to process the document in R and externally to work with the code and create documents. We have added our own XML elements and use the namespaces http://www.r-project.org and http://www.omegahat.org to identify these elements.

One can browse these documents directly in a good Web browser as they have the associated XSL stylesheet referenced within them. One can also use XSL to convert them to HTML or PDF (via FO) and indeed one can convert them to LaTeX and then process them via that tool chain.

And one can read and execute the code in R directly from the document using the XML package and the function xmlSource() available from xmlInternalSource.R. You can load this into R using

source(url("http://www.omegahat.org/xmlInternalSource.R"))

xmlSource("http://www.omegahat.org/RwxWidgets/ExampleDocuments/menu.xml")

xmlSource(""http://www.omegahat.org/RwxWidgets/ExampleDocuments/DragNDrop.xml", xpath = "//r:example[@id='DynamicDnD']")