/// <summary>
/// Load the contents of a file from the windows file system into memory and display it.
/// </summary>
/// <param name="filename"></param>
public override void LoadFile(string filename)
{
// Look-up plugin model
string plugin = this.dm_DocumentDataModel.PluginModelName;
PluginModelBase m = PluginManager.GetPluginModel(plugin);
// Look-up shape converter
UmlTypeToStringConverterBase conv = null;
conv = m.ShapeConverter;
// Convert Xml document into a list of shapes and page definition
List <ShapeViewModelBase> coll;
PageViewModelBase page = conv.LoadDocument(filename, _CanvasViewModel, out coll);
// Apply new page and shape definitions to data model
_DataModel.LoadFileFromCollection(page, coll);
this.prop_DocumentFilePath = filename;
this.vm_CanvasViewModel.SelectedItem.Clear();
}