/////////////////////////////////////////////////////////////////////
// BrowseForm.cpp - implements Browser members using parent form   //
//                                                                 //
// Jim Fawcett, CSE687 - Object Oriented Design, Spring 2004       //
/////////////////////////////////////////////////////////////////////
// Notes:                                                          //
//   The member functions implemented here can't be inlined in     //
//   BrowseForm.h.  That would required including the Form1.h      //
//   header in BrowseForm.h.  But Form1.h already includes the     //
//   BrowseForm.h file, and mutual includes between header files   //
//   don't work.                                                   //
/////////////////////////////////////////////////////////////////////

#include "StdAfx.h"
#include "BrowseForm.h"
#include "Form1.h"
using namespace demoWinForm;

//----< build tree after form loads >--------------------------------

System::Void BrowseForm::BrowseForm_Load(
      System::Object ^  sender, System::EventArgs ^  e)
{
  tvPlus1->buildTree();
}
//----< enables me to callback on my parent form >-------------------

void BrowseForm::setBaseForm(Form^ baseForm)
{
  _baseForm = baseForm;
}
//
//----< event handler that sends selected path back to parent >------

System::Void BrowseForm::tvPlus1_AfterSelect(
  System::Object ^  sender, System::Windows::Forms::TreeViewEventArgs ^  e)
{
  if(!_first)  // don't call back if this is first selection
  {
    String^ path = e->Node->FullPath;
    Form1^ pForm = static_cast<Form1^>(_baseForm);

  ///////////////////////////////////////////////////////
  // statement below is simple way to communicate with
  // parent form, but not as flexible as delegate-based
  // method used here
  //   pForm->setPath(path);

  // set up delegate argument

    array<String^>^ argArray = gcnew array<String^>(1);
    argArray[0] = path;

  // invoke delegate to callback on parent form's setPathEvent handler
  // in way that is safe even if called from a thread that did not create 
  // form

    if(pForm->InvokeRequired)
  //
  // here is the syntax that looks like it should work, but fails with
  // the strange error message: "must be a data member" which it is.
  //
  //    pForm->BeginInvoke(setPathEvent, argArray);
  //
  // I'm creating a new delegate instance instead of using the cached instance
  //
  // called by worker thread
  //
      pForm->BeginInvoke(gcnew setPathDelegate(pForm,&Form1::setPath), argArray);
    else
  //
  //  called by UI thread
  //
      setPathEvent(path);
    return;
  }
  _first = false;
}