Delphi 2010 How do I Implement a Hydra WPF host application sample?

Question

Continuing with our Delphi 2010 thick client to multi-tier migration (previous question), we are at the point where we need to find a databinding solution. I have come across RemObjects Hydra. The thing is I can't seem to follow their tutorials for the host program and for the plugin I have created a Hydra plugin project in visual studio, implemented the interface as described and that builds fine.

[Guid("8F1B3EE3-CC69-4685-B141-FAF2F4FB57C4")]
public interface IGridPlugin : IHYCrossPlatformInterface
{
    string UserData { get; set; }
    int ID { get; set; }

}

In the plugin:

[Plugin(Name = "GridPlugin", Description = "This is the Grid plugin", UserData = "Data"), VisualPlugin]
public partial class GridPlugin : RemObjects.Hydra.WPF.VisualPlugin, IGridPlugin
{

In Delphi I have created a new Hydra host project, imported the interface, but in the form create/load events they mention:

procedure TMainForm.FormCreate(Sender: TObject);
begin
  ModuleManager.LoadModule('SilverlightPlugin.xap');
  ModuleManager.CreateVisualPlugin('SilverlightPlugin', fInstance, Panel1);
end;

What is fInstance? Also, no files in my WPF plugins project end in .xap, so what am I supposed to pass as a parameter?

Has anyone implemented RemObjects Hydra, how did you achieve this early step? Any help will be appreciated.

Hydra should contain sample projects which show how to use it. Also for the Delphi Host you might refer to this article as you have a WPF plugin and not a silverlight one: http://wiki.remobjects.com/wiki/VCL_Host — Stefan Glienke, Oct 05 '12 at 21:26
Thanks. I got it working in the end. The example didn't declare fInstance, but one of the other videos ([LINK]http://www.remobjects.com/tv/hydra.aspx?video=hydra-02-firemonkey) explained (after writing the method call to CreateVisualPlugin) the need to declare it, and more crucially what it is - fInstance: IHYVisualPlugin; — reckface, Oct 09 '12 at 12:49

score 1 · Accepted Answer · answered Oct 09 '12 at 12:59

This is how I got it working in the end, you need to declare an instance of the plugin:

Private
  fInstance: IHYVisualPlugin;

// Then Call in the FormCreate event
procedure TMainForm.FormCreate(Sender: TObject);
begin
    ModuleManager.LoadModules('C:\Users\user.Name\Documents\Visual Studio 2010\Projects\DynamicEF4\Product.Delphi.WPF\BIN\RELEASE\Product.Delphi.WPF.dll');
   ModuleManager.CreateVisualPlugin('ViewerPlugin', fInstance, pnl1);
end;
// And then in the FormDestroy event
procedure TMainForm.FormDestroy(Sender: TObject);
begin
    ModuleManager.ReleaseInstance(fInstance);
end;

I guess I was looking at the wrong example, the .xap I saw related to silverlight, and not required for wpf or windows forms.

Delphi 2010 How do I Implement a Hydra WPF host application sample?

1 Answers1