I know that it is possible to load xap modules dynamically using Prism or MEF framework. However, I'd like not to use those frameworks; instead load my xap files manually. So, I created the following class (adapted from internet):
public class XapLoader
{
public event XapLoadedEventHandler Completed;
private string _xapName;
public XapLoader(string xapName)
{
if (string.IsNullOrWhiteSpace(xapName))
throw new ArgumentException("Invalid module name!");
else
_xapName = xapName;
}
public void Begin()
{
Uri uri = new Uri(_xapName, UriKind.Relative);
if (uri != null)
{
WebClient wc = new WebClient();
wc.OpenReadCompleted += onXapLoadingResponse;
wc.OpenReadAsync(uri);
}
}
private void onXapLoadingResponse(object sender, OpenReadCompletedEventArgs e)
{
if ((e.Error == null) && (e.Cancelled == false))
initXap(e.Result);
if (Completed != null)
{
XapLoadedEventArgs args = new XapLoadedEventArgs();
args.Error = e.Error;
args.Cancelled = e.Cancelled;
Completed(this, args);
}
}
private void initXap(Stream stream)
{
string appManifest = new StreamReader(Application.GetResourceStream(
new StreamResourceInfo(stream, null), new Uri("AppManifest.xaml",
UriKind.Relative)).Stream).ReadToEnd();
XElement deploy = XDocument.Parse(appManifest).Root;
List<XElement> parts = (from assemblyParts in deploy.Elements().Elements()
select assemblyParts).ToList();
foreach (XElement xe in parts)
{
string source = xe.Attribute("Source").Value;
AssemblyPart asmPart = new AssemblyPart();
StreamResourceInfo streamInfo = Application.GetResourceStream(
new StreamResourceInfo(stream, "application/binary"),
new Uri(source, UriKind.Relative));
asmPart.Load(streamInfo.Stream);
}
}
}
public delegate void XapLoadedEventHandler(object sender, XapLoadedEventArgs e);
public class XapLoadedEventArgs : EventArgs
{
public Exception Error { get; set; }
public bool Cancelled { get; set; }
}
The above code works fine; I can load any xap the following way:
XapLoader xapLoader = new XapLoader("Sales.xap");
xapLoader.Completed += new XapLoadedEventHandler(xapLoader_Completed);
xapLoader.Begin();
Now, I have a UserControl called InvoiceView in the Sales.xap project, so I would like to instantiate the class. In the current project (Main.xap) I added reference to Sales.xap project, however, since I load it manually I set "Copy Local = False". But when executed, the following code throws TypeLoadException:
Sales.InvoiceView view = new Sales.InvoiceView();
It seems the code can't find InvoiceView class. But I checked that XapLoader's initXap() method was successfully executed. So why the code can't find InvoiceView class? Can someone help me with this problem?
