C / C++ / MFC

17-Mar-08 20:00

I am trying to create shell context menu , I want to dispaly the path of file that on the right click of my menu item. Program displaying the path of file very well except the shortcut file path(.lnk file).

When I click on .lnk file, It display the target file path but I want shortcut file path, even this is also a file.
I asked this quetion before and someone suggest me the following:
"The shell resolves the links before calling 'InvokeCommand()', so you always will receive the link target."

But some also suggest me:
"You can register as a handler for .lnk files. If you don't do that, the shell with automatically follow the link and pass the target file to your extension."

I tried the above method but I could not get the .lnk file path. So could you please tell me how to get the .lnk file path using shell context menu.

rp_suman17-Mar-08 20:39

rp_suman

17-Mar-08 20:39

If you give meaningful subject, you may get help quickly.
Like "Getting path to .lnk file" or else.

Best Regards,
Suman

john563217-Mar-08 20:42

17-Mar-08 20:42

I have asked this question many times with meaningful subject but nobody respond me.

rp_suman17-Mar-08 21:55

rp_suman

17-Mar-08 21:55

They might not see your question who knows answer.
In that case, we cant bother anybody and we need to google or search in MSDN or look for some other way ourself..
I hope you will find solution soon

Best Regards,
Suman Smile | :)

David Crow18-Mar-08 3:55

David Crow

18-Mar-08 3:55

pther wrote:
I have asked this question many times with meaningful subject but nobody respond me.

Which could indicate to you that we may not know the answer. Continuing to ask the same question over and over will not change that.

"Normal is getting dressed in clothes that you buy for work and driving through traffic in a car that you are still paying for, in order to get to the job you need to pay for the clothes and the car and the house you leave vacant all day so you can afford to live in it." - Ellen Goodman

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

Naveen17-Mar-08 21:21

Naveen

17-Mar-08 21:21

Suppose you register the extension handler under both * and .lnk as follows,

NoRemove lnkfile<br />
  {<br />
    NoRemove ShellEx<br />
    {<br />
      NoRemove ContextMenuHandlers<br />
      {<br />
        ForceRemove Myshell = s '{B3490870-0081-45C4-AE05-C4B7E788BC29}'<br />
      }<br />
    }<br />
  }<br />
<br />
  NoRemove *<br />
  {<br />
    NoRemove ShellEx<br />
    {<br />
      NoRemove ContextMenuHandlers<br />
      {<br />
        ForceRemove Myshell = s '{B3490870-0081-45C4-AE05-C4B7E788BC29}'<br />
      }<br />
    }<br />
  }

The Initialize()function will be called twice. In the first call, it will passing target files name. But when it gets called for the second time, you will get the path of the lnk.

nave

[OpenedFileFinder]

john563217-Mar-08 22:50

17-Mar-08 22:50

I also tried this too and I put a messagebox to display the selected file path. But it appears only once not twice.

my code for Initialize()

<br />
<br />
HRESULT __stdcall CCoMenHandler::Initialize(LPCITEMIDLIST pidlFolder, IDataObject *pdtobj, HKEY hkeyProgID)<br />
{<br />
	//Store the PIDL.<br />
    if(pidlFolder)<br />
        m_pIDFolder = pidlFolder;<br />
	<br />
    // If Initialize has already been called, release the old<br />
    // IDataObject pointer.<br />
    if (m_pDataObj)<br />
        m_pDataObj->Release(); <br />
<br />
	 // duplicate the object pointer and registry handle<br />
   if (pdtobj)<br />
   {<br />
	   m_pDataObj = pdtobj;<br />
	   pdtobj->AddRef();<br />
   } <br />
   else<br />
   {<br />
	   return E_FAIL;<br />
   }<br />
   <br />
   //get these paths into a CStringArray<br />
   g_szSelectedFiles.RemoveAll();<br />
<br />
   //fetch all of the file names we're supposed to operate on<br />
   if (pdtobj) <br />
   {<br />
	   pdtobj->AddRef();<br />
<br />
	   STGMEDIUM medium;<br />
	   FORMATETC fe = { CF_HDROP, NULL, DVASPECT_CONTENT, -1, TYMED_HGLOBAL};<br />
<br />
	   HRESULT hr = pdtobj->GetData (&fe, &medium);<br />
	  	  <br />
	   if (FAILED (hr))<br />
	   {<br />
		   	g_bRecyleBin=TRUE;<br />
			GetRecycleBinFiles();//I could not detect the name of RecycleBin Folder on right click<br />
			return ;<br />
	   }<br />
	   else<br />
		g_bRecyleBin=FALSE;<br />
<br />
	   // buffer to receive filenames<br />
	   char path[MAX_PATH];<br />
<br />
	  	 // how many are there?<br />
	   UINT fileCount = DragQueryFile((HDROP)medium.lpszFileName, 0xFFFFFFFF,path, MAX_PATH);<br />
	  	   <br />
 	   if (fileCount>0)<br />
	   {<br />
		   // avoid wasting mem when this thing gets filled in<br />
		   g_szSelectedFiles.SetSize(fileCount);<br />
		   <br />
		   // stash the paths in our CStringArray<br />
		 for (UINT i=0;i<fileCount;i++) <br />
         {<br />
			  // clear old path<br />
			  memset(path, 0, MAX_PATH);<br />
			   // fetch new path<br />
			if (DragQueryFile((HDROP)medium.lpszFileName, i, path, MAX_PATH)) <br />
            {<br />
				g_szSelectedFiles.SetAt(i, path);<br />
AfxMessageBox(path);<br />
				<br />
				<br />
			}<br />
					      <br />
	      }<br />
         g_szSelectedFiles.FreeExtra();<br />
      }<br />
      // free our path memory - we have the info in our CStringArray<br />
      ReleaseStgMedium(&medium);<br />
   }   return S_OK;<br />
}<br />

So how could I get it.

Naveen17-Mar-08 23:29

Naveen

17-Mar-08 23:29

pther wrote:
I put a messagebox

Did u check by putting a break point in the first line of Initialize() function?

In your code message box in the end. There is a chance that some of your checking might have failed and the control might have returned before the messagebox. So just for debugging purpose modify your initilaze function such that in contains a AfxMessageBox.

HRESULT __stdcall CCoMenHandler::Initialize(LPCITEMIDLIST pidlFolder, IDataObject *pdtobj, HKEY hkeyProgID)
{
AfxMessageBox( _T("Initialize called"));
return S_OK;
}

In this case also if only one message box came, paste the rgs file content here.

nave

[OpenedFileFinder]

john563218-Mar-08 0:08

18-Mar-08 0:08

Thank you

It is working for link file. But not working for Internet Shortcut file.

I am so thankful to you. I hope you will also assist me to get it.

Naveen18-Mar-08 0:19

Naveen

18-Mar-08 0:19

pther wrote:
But not working for Internet Shortcut file.

For that i think u need to register under the InternetShortcut key. I didnt try

NoRemove InternetShortcut
{
NoRemove ShellEx
{
NoRemove ContextMenuHandlers
{
ForceRemove Myshell = s '{B3490870-0081-45C4-AE05-C4B7E788BC29}'
}
}

nave

[OpenedFileFinder]

john563218-Mar-08 0:29

18-Mar-08 0:29

Naveen, You help me a lot Smile | :)

.

i am Very Very Thankful to you.

May I get your personal email id, if you do not mind.

Inheritance in Pimpl idiom

fat_boy18-Mar-08 2:47

fat_boy

18-Mar-08 2:47

Another crappy Indian programmer who cant work it out for themselves!

Morality is indistinguishable from social proscription

George_George17-Mar-08 19:31

17-Mar-08 19:31

Hello everyone,

Why it is useless for any inheritance in Pimpl idiom? Here is the source, but no detailed reasons are provided.

http://www.gotw.ca/gotw/024.htm

--------------------
- make XImpl entirely the class that X would have been, and write X as only the public interface made up entirely of simple forwarding functions (a handle/body variant).

This is useful in a few restricted cases, and has the benefit of avoiding a back pointer since all services are available in the pimpl class. The chief drawback is that it normally makes the visible class useless for any inheritance, as either a base or a derived class.
--------------------

thanks in advance,
George

Maxwell Chen17-Mar-08 20:01

17-Mar-08 20:01

I can reply this. But please wait for me to type because I can not copy-and-paste. Big Grin | :-D

Maxwell Chen

George_George17-Mar-08 22:01

Re: Inheritance in Pimpl idiom [modified]

17-Mar-08 22:01

Can you provide a link, Maxwell? I can look up by myself. Smile | :)

regards,
George

Maxwell Chen17-Mar-08 20:43

17-Mar-08 20:43

The below is the original Pimpl model. The opaque pointer is the private member.

To test this with Visual C++ (2005), you need to put the declarations of class X and class X::XImpl with their member function prototypes in individual .h files, and put the implementations of member functions in individual .cpp files.

// x.h
class X
{
private:
  class XImpl;
  XImpl* pimpl_;
public:
  bool Foo(long);
protected:
  int Bar(short);
};
// ximpl.h
class X::XImpl
{
public:
  bool Function();
  // ...
};
// x.cpp
bool X::Foo(long v)
{
  return pimpl_->Function();
}
// ximpl.cpp
bool X::XImpl::Function()
{
  // ...
  return true;
}

What does it mean To make XImpl entirely the class X would have been?
That is, you move ~~X::Foo and~~ X::Bar into class X::XImpl.

Code snippet below.

// x.h
class X2  // New generation.
{
private:
  class XImpl;
  XImpl* pimpl_;
public:
  bool Foo(long); // Leave this as the only public interface.
};
// ximpl.h
class X2::XImpl
{
public:
  bool Function();
protected:
  int Bar(short); // Move all the implementations of X into here, so no backpointer is needed.
};

How will we use this revision? Still the same.

X2 obj;
if(obj.Foo() /* invoke the opaque Function() */ ) {
 // ...
}

So now we talk about the inheritance. See the comments in the code snippet below.

class Y : public X2
{
public:
  bool Test() {
    // Oops!! 
    // No access to Bar().
    // No access to Pimpl.
    return false;
  }
  // ...
};

Maxwell Chen

modified on Tuesday, March 18, 2008 4:04 AM

George_George17-Mar-08 22:14

17-Mar-08 22:14

Thanks for providing a comprehensive sample, Maxwell!

1.

One question, why do you want to call Bar and Pimpl in method Test of class Y? If we put something (like Bar) in Pimpl part, it means it is not visible. So, I think it does not make senses to access Bar if it is in Pimpl part. Any comments?

2.

I think you can still access Foo in class Y, right?

regards,
George

Maxwell Chen17-Mar-08 23:00

17-Mar-08 23:00

George_George wrote:
why do you want to call Bar and Pimpl in method Test of class Y? If we put something (like Bar) in Pimpl part, it means it is not visible. So, I think it does not make senses to access Bar if it is in Pimpl part. Any comments?

My code sample was just sort of excerpt. After all, you have to deal with class X or class Y in real life.

Let's take CDialog::OnInitDialog() of MFC for example. You created a dialog based project, so you have the below code.

In function implementation of CTestDlg::OnInitDialog, you need to do many things. For example: calling the base's member function CWnd::GetSystemMenu() to manipulate the title-box menu; calling CWnd::SetIcon to manipulate icons, etc.

class CTestDlg : public CDialog  // class Y : public X
{
protected:
  virtual BOOL OnInitDialog(void);
  // ...
};
BOOL CTestDlg::OnInitDialog()
{
  // ...
  CMenu* pMenu = GetSystemMenu(FALSE); // This is something like invoking X::Bar().
  // ...
}

The article and I are not talking it making sense or not to access Bar if it is moved into Pimpl; We are talking about: Sometimes a certain design paradigm will shoot your own feet.

George_George wrote:
I think you can still access Foo in class Y, right?

See my answer to (1) as the above.

My questions to you:
1) George, are you still at school or are you working at some company?
2) After you have been asking various beginner ~ expert level questions, do you really feel you are getting better in C++?
3) Are the questions you have asked here really useful to your homework or your real-world job?

Maxwell Chen

George_George17-Mar-08 23:26

17-Mar-08 23:26

Thanks Maxwell,

I have read and understand the sample. Do you mean the pattern of MFC dialog is good or not? Does it relates to my original question?

My answers to your 3 questions,

1) private Smile | :)

2) sure, expecially from you;
3) some from books, some from the comments from you.

regards,
George

Maxwell Chen17-Mar-08 23:53

17-Mar-08 23:53

George_George wrote:
Do you mean the pattern of MFC dialog is good or not?

I am not a MFC pro. Nor am I so much picky.
Things working smoothly will do. As cats being able to catch mice are considered good cats. Big Grin | :-D

And I sometimes branch the patterns to what I want. (I am evil.) Laugh | :laugh:

George_George wrote:
Does it relates to my original question?

Yes it does dedicate to asnwering your original question, regarding class X and the derived Y.

Maxwell Chen

George_George18-Mar-08 0:17