Re: Help with multi-sort - C / C++ / MFC Discussion Boards

Hi,
thank you! This works ! Even if the dialog resource is within a DLL.

Thank you very much !

Hi, me again...

I have done several tests in the meantime and unfortunatelly there is still a small problem with the tooltip.
To setup the tooltips for the modeless dialog in my dll I use this function:
//////////////////////////////////////////
void CMyDialog::SetToolTip(CWnd* pWnd, LPCTSTR lpszText)
{
if((pWnd != NULL) && (m_pTip != NULL)){
TOOLINFO ti;
ti.cbSize = sizeof(TOOLINFO);
ti.lpszText = (LPTSTR)lpszText;
ti.hinst = AfxGetInstanceHandle();
ti.hwnd = pWnd->m_hWnd;
ti.uFlags = TTF_SUBCLASS | TTF_IDISHWND;
ti.uId = (UINT)pWnd->m_hWnd;
m_pTip->SendMessage(TTM_ADDTOOL, 0, (LPARAM)&ti);
}
}
//////////////////////////////////////////

This works without (!) any call to CMyDialog::PreTranslateMessage(MSG* pMsg). But I need this call, because there is an MFC bug with tooltips for disabled controls and I used in my modal dialogs this code:

//////////////////////////////////////////
BOOL CMyDialog::PreTranslateMessage(MSG* pMsg)
{
TRACE("PreTranslateMessage\n");

if(m_pTip != NULL){
// The following code is a workaround for a MFC tooltip bug which
// prevents the popup of a tooltip for a disabled control in a modal dialog.

// Transate the message based on TTM_WINDOWFROMPOINT
MSG msg = *pMsg;
msg.hwnd = (HWND)m_pTip->SendMessage(TTM_WINDOWFROMPOINT, 0, (LPARAM)&msg.pt);
CPoint pt = pMsg->pt;
if((msg.message >= WM_MOUSEFIRST) && (msg.message <= WM_MOUSELAST))
::ScreenToClient(msg.hwnd, &pt);
msg.lParam = MAKELONG(pt.x, pt.y);

// Let the ToolTip process this message.
m_pTip->RelayEvent(&msg);
} // if
return CDialog::PreTranslateMessage(pMsg);
}
//////////////////////////////////////////

Then I tried to use the message hook which was neccessary to use accellerators in CMyDialog:

//////////////////////////////////////////
// Hook procedure for WH_GETMESSAGE hook type.
LRESULT CALLBACK GetMessageProc(int nCode, WPARAM wParam, LPARAM lParam)
// If this is a keystrokes message, translate it in controls'
// PreTranslateMessage().
LPMSG lpMsg = (LPMSG)lParam;

if((nCode >= 0) &&
(PM_REMOVE == wParam) &&
(lpMsg->message >= WM_KEYFIRST && lpMsg->message <= WM_KEYLAST) &&
(AfxGetApp()->PreTranslateMessage((LPMSG)lParam)) == TRUE){
// The value returned from this hookproc is ignored, and it cannot
// be used to tell Windows the message has been handled. To avoid
// further processing, convert the message to WM_NULL before
// returning.
lpMsg->message = WM_NULL;
lpMsg->lParam = 0L;
lpMsg->wParam = 0;
}

if((nCode >= 0) &&
(PM_REMOVE == wParam) &&
(lpMsg->message >= WM_MOUSEFIRST && lpMsg->message <= WM_MOUSELAST) &&
(AfxGetApp()->PreTranslateMessage((LPMSG)lParam)) == TRUE){

// Do nothing ???

}
// Passes the hook information to the next hook procedure in
// the current hook chain.
return ::CallNextHookEx(g_hHook, nCode, wParam, lParam);
}
//////////////////////////////////////////

When I use the above code the tooltips for disabled controls work, but something with the mosemessage handling is wrong, because CCombobox Controls can't be opened.

Does anyone kwon how to solve my problem ?? I think somehow I must call RelayEvent of the tooltip.

THX

I had the same issue.
And now, thanks to your suggestion it works.

I switched from:

m_toolTip.AddTool(this,ttwtext.c_str(),cr,1);

To

TOOLINFO ti;

ti.cbSize = sizeof(TOOLINFO);
ti.lpszText = (LPTSTR)last_ttwtext.c_str();
ti.hinst = AfxGetInstanceHandle();
ti.hwnd = this->GetSafeHwnd();
ti.uFlags = TTF_SUBCLASS | TTF_IDISHWND;
ti.uId = (UINT) this->GetSafeHwnd();

m_toolTip.SendMessage(TTM_ADDTOOL, 0, (LPARAM) &ti);

Thanks!

Hi, me again...

I have done several tests in the meantime and unfortunatelly there is still a small problem with the tooltip.
To setup the tooltips for the modeless dialog in my dll I use this function:
//////////////////////////////////////////
void CMyDialog::SetToolTip(CWnd* pWnd, LPCTSTR lpszText)
{
if((pWnd != NULL) && (m_pTip != NULL)){
TOOLINFO ti;
ti.cbSize = sizeof(TOOLINFO);
ti.lpszText = (LPTSTR)lpszText;
ti.hinst = AfxGetInstanceHandle();
ti.hwnd = pWnd->m_hWnd;
ti.uFlags = TTF_SUBCLASS | TTF_IDISHWND;
ti.uId = (UINT)pWnd->m_hWnd;
m_pTip->SendMessage(TTM_ADDTOOL, 0, (LPARAM)&ti);
}
}
//////////////////////////////////////////

This works without (!) any call to CMyDialog::PreTranslateMessage(MSG* pMsg). But I need this call, because there is an MFC bug with tooltips for disabled controls and I used in my modal dialogs this code:

//////////////////////////////////////////
BOOL CMyDialog::PreTranslateMessage(MSG* pMsg)
{
TRACE("PreTranslateMessage\n");

if(m_pTip != NULL){
// The following code is a workaround for a MFC tooltip bug which
// prevents the popup of a tooltip for a disabled control in a modal dialog.

// Transate the message based on TTM_WINDOWFROMPOINT
MSG msg = *pMsg;
msg.hwnd = (HWND)m_pTip->SendMessage(TTM_WINDOWFROMPOINT, 0, (LPARAM)&msg.pt);
CPoint pt = pMsg->pt;
if((msg.message >= WM_MOUSEFIRST) && (msg.message <= WM_MOUSELAST))
::ScreenToClient(msg.hwnd, &pt);
msg.lParam = MAKELONG(pt.x, pt.y);

// Let the ToolTip process this message.
m_pTip->RelayEvent(&msg);
} // if
return CDialog::PreTranslateMessage(pMsg);
}
//////////////////////////////////////////

Then I tried to use the message hook which was neccessary to use accellerators in CMyDialog:

//////////////////////////////////////////
// Hook procedure for WH_GETMESSAGE hook type.
LRESULT CALLBACK GetMessageProc(int nCode, WPARAM wParam, LPARAM lParam)
// If this is a keystrokes message, translate it in controls'
// PreTranslateMessage().
LPMSG lpMsg = (LPMSG)lParam;

if((nCode >= 0) &&
(PM_REMOVE == wParam) &&
(lpMsg->message >= WM_KEYFIRST && lpMsg->message <= WM_KEYLAST) &&
(AfxGetApp()->PreTranslateMessage((LPMSG)lParam)) == TRUE){
// The value returned from this hookproc is ignored, and it cannot
// be used to tell Windows the message has been handled. To avoid
// further processing, convert the message to WM_NULL before
// returning.
lpMsg->message = WM_NULL;
lpMsg->lParam = 0L;
lpMsg->wParam = 0;
}

if((nCode >= 0) &&
(PM_REMOVE == wParam) &&
(lpMsg->message >= WM_MOUSEFIRST && lpMsg->message <= WM_MOUSELAST) &&
(AfxGetApp()->PreTranslateMessage((LPMSG)lParam)) == TRUE){

// Do nothing ???

}
// Passes the hook information to the next hook procedure in
// the current hook chain.
return ::CallNextHookEx(g_hHook, nCode, wParam, lParam);
}
//////////////////////////////////////////

When I use the above code the tooltips for disabled controls work, but something with the mosemessage handling is wrong, because CCombobox Controls can't be opened.

Does anyone kwon how to solve my problem ?? I think somehow I must call RelayEvent of the tooltip.

THX

I have a CArray of structs and I would like to sort my multiple members of the struct. Say it's a person struct and I want to sort by last name & age. Or maybe last name, first name, and age. Anyone have a clue how to do this?

Thanks
Kurt

Hi,
Will this Suffice , then implement the callback

// call the functions: First sort with name
qsort(qsortdata, count, sizeof(struct Person), qsort_callbackName);
// then sort the required ones age etc
qsort(qsortdata, count-noidfiles, sizeof(struct Person), qsort_callbackAge);

(IMHO)

Regards,
FarPointer

-- modified at 13:06 Friday 31st March, 2006

What do you mean by this in the second sort? count-noidfiles

Well what iam actually doing is that first i will sort with respect to the name ,then sort the sorteddata with respect to the age .

int qsort_callback(const void * first, const void * second)<br />
{<br />
	struct person  *p1, * p2;<br />
	p1 = (struct person *)first;<br />
	p2 = (struct person *)second;<br />
       //According to your preference <br />
       if( (*(p1->Name)).Compare(*(p2->Name)) >0 )<br />
	{<br />
                //for the age <br />
		if(p1->Age > p2->Age)<br />
			return 1;<br />
		if(p1->Age < p2->Age)<br />
			return -1;		<br />
	}<br />
        //else same way as above <br />
<br />
}

// Well here i have tried to make sorting in one go as David says qsort is not stable one but the previous one is more logical clear ,like if later we need a more customization on the sort you again sort on the sorted data
Regards,
FarPointer

-- modified at 13:20 Friday 31st March, 2006

FarPointer wrote:
...but the previous one is more logical clear ,like if later we need a more customization on the sort you again sort on the sorted data

For reasons already mentioned, calling qsort() again on the sorted list using a different key will not work.

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

FarPointer wrote:
Will this Suffice

No, because qsort() is not a stable sort. You would need to combine the effects of qsort_callbackName() and qsort_callbackAge() and call qsort() only once.

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

Wat do you mean by not a stable sort ,it should be a well tested and implemented one right(IMHO).

Regards,
FarPointer

Stable sorting algorithms maintain the relative order of records with equal keys. If whenever there are two records A and B with the same key and with A appearing before B in the original list, A will appear before B in the sorted list, the algorithm is said to be stable.

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

Well thanks for making it clear .

Regards,
FarPointer

Thanks for the refresher course David.

Smile | :)

Maximilien Lincourt
Your Head A Splode - Strong Bad

David

Can you show me an example?

int bynameinage( const void * v1, const void * v2 )
{
    pmyData data1 = *(pmyData *) v1;
    pmyData data2 = *(pmyData *) v2;
    
    int dt = data1->age - data2->age;
    
    if (dt != 0)
        return dt;
 
    // same age so check name
    return _tcscmp(data1->name, data2->name);    
}
...
qsort(..., bynameinage);

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

Neat and Clean.

Regards,
FarPointer

Probably a fairly common problem, but I'm having difficulty getting precisely the answer I need, so I'm asking a different way.
I have an MFC class (actually a dialog) in my app that I need to shift out to a DLL. There's a major product rearchitecture looming, so this is a short-term problem I need to solve. It doesn't have to be pretty, but it does need to be quick to implement.
Of course, to make my life difficult, the DLL will need to call a couple of class methods from back in the app. A typical example would be the dialog in the DLL has a Help button that, when pressed, launches a Help() method back in the app.

I'm thinking I make a "Callback" class, which exposes only the methods I need. The app creates one of these and sets up the "inside" objects it needs to know about, and the DLL itself only needs to know about this callback class. Is this the right approach?

At this point I'm stuck. I know I'm trying to hack a solution to a bad early design decision, but luckily this is only short term (but needs to be done).

Like I say, I've searched but so far haven't found any example code that deals with this specifically. Lots of "generic" stuff that mostly talks about C functions and "mentions" class callbacks. I could use a nudge in the right direction.

Brad.

Why not create an instance of the class and pass it to your dll?

That was rather the approach I was thinking of. But the class (let's call it CCallback) needs to have knowledge of a fair amount of the main app (ie. the implementation of CCallback requires a fair number of #includes from other app classes that the DLL need not know about).

I might just not be looking at this from the right angle (I've been dealing with COM stuff for so long that I've probably lost sight of the basics). But I have my CCallback.h, which I #include in the DLL code so it knows what my class looks like. That's fine for compiling, but the linker complains about all the unresolved externals.

Do you have your lib for your dll linked into the app?

Yes. It's actually the DLL linking that's complaining. So I think I'm just not declaring my CCallback class correctly *within* the DLL code. Once I can get the DLL to understand how to call back, then I can work on getting my app to actually call into the DLL (I haven't even go there yet, probably doing this backwards).

You might need to app the .cpp to your dll project

Which has intimate knowledge of the app classes, which the DLL doesn't want to know about. So it'll never compile.

Yeah looks like callbacks might be the way to go.