TMyClass = class
    ...
  public
    property OnMyEvent: TNotifyEvent ... ;
  end;

  C := TMyClass.Create;
  C.OnMyEvent := MyEvent;

public class ActivityLogin extends Activity {

    public void btnLoginOnClick(View v) {

    	NotifyEvent ne = new NotifyEvent() 
    	{

		@Override
		public void run() {
			if (data == null) return;
			final NetAdminAPIRequest req = (NetAdminAPIRequest)data;
			runOnUiThread(new NotifyEvent()
			{
				@Override
				public void run() {
					Log.i("NetAdmin", req.errorStr);
				}
			});
			
		}
    	};
    	
    	try
    	{
    		api.reqLogin("admin", "wer", ne);
    	} catch (Throwable e) 
    	{
    		Log.e("NetAdmin", e.toString());
    	}
    }
    
} 

public class NetAdminAPI {
	
	public void reqLogin(String login, String password, NotifyEvent onDone) throws Throwable {
		
                   ...

		final NetAdminAPIRequest req = new NetAdminAPIRequest();
		req.onDone = onDone;

		new Thread()
		{
			public void run()
			{
                                         ...
				
				if (req.onDone != null)
				{
					req.onDone.data = req;
					req.onDone.run();
				}
			}
		}.start();
	}
}

public class NetAdminAPIRequest {
	public String response = "";
	public String errorStr = "";
	public NotifyEvent onDone = null;
}

public abstract class NotifyEvent implements Runnable {
	public Object data = null;
}