C / C++ / MFC

Re: Driving Ctatic::DrawItem

10-Dec-18 15:16

I have an owerdraw ComboBox When a user selects an Item I want to Display the Detail info

I figure I could use the same Dialog for Background

So for the 6 CStatic and Their 6 Labels I do ShowWindow(SW_HIDE)

I saw the following post on how to drive DrawItem by Calling invalidate an the SetWindowText

Getting owner draw child control to paint when calling SetWindowText - vc.mfc[^]

So I create my own derived CStatic

C++

class MyStatic : public CStatic
{ DECLARE_DYNAMIC(MyStatic)
public:
	MyStatic();
	~MyStatic();
	
	void SetWindowText(LPSTR);
	void DrawItem(LPDRAWITEMSTRUCT pdis);

};

This my SSetWindowText

C++

void MyStatic::SetWindowText(LPSTR lpsz)
{
	Invalidate();
	CStatic::SetWindowText(lpsz);

}

two bad things on the way to getting where I want

1) I get an exception in wincore.cpp at the retrun ::CallWindowProc

C++

RESULT CWnd::DefWindowProc(UINT nMsg, WPARAM wParam, LPARAM lParam)
{
	if (m_pfnSuper != NULL)
		return ::CallWindowProc(m_pfnSuper, m_hWnd, nMsg, wParam, lParam);

	WNDPROC pfnWndProc;
	if ((pfnWndProc = *GetSuperWndProcAddr()) == NULL)
		return ::DefWindowProc(m_hWnd, nMsg, wParam, lParam);
	else

2) After the exception my Drawitem is called however ItemData doesn't have the String pointer and and is NULL

Thanks

ForNow11-Dec-18 15:58

Re: What is the learning path?

11-Dec-18 15:58

Didn't have a message map entry from my Derived CStatic

also the text of the Static control isn't set in the itemData you have to a GetWindowText to get it

with those two fixes everything worked

有什么学习途径

Member 140765679-Dec-18 20:30

Member 14076567

9-Dec-18 20:30

有什么学习MFC的途径和论坛，我是MFC软件开发的。

Richard Deeming11-Dec-18 1:09

Richard Deeming

11-Dec-18 1:09

Member 14076567 wrote:
What are the ways and forums for learning MFC, I am developing MFC software.

This is an English-language site. Please post questions in English.

Via Google Translate:
这是一个英语网站。请用英文发布问题。

"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer

AfxMessage doesn’t block

ForNow6-Dec-18 2:02

6-Dec-18 2:02

Hi
I’m again having different results in debug and release this one isn’t a bug but different program behavior.
I have 4 CwinThread Wrappers for CAsynSocket
In debug because processing is slowed somewhat by int 3 breakpoints I Receive all my about 3500 bytes of data from the Mainframe computer. In release I don’t get it all in one transmission I have a full word or a short int in the begging of the stream to tell me how much data
My method to debug this in the past was issue a AfxMessage and attach the debugger
This always seemed to work with the Mainthread
I didn’t even notice the message box come up in this scenario except by hovering my mouse on the tray at the bottom of the screen I don’t think I can use __debugbreak in Release
Anyway to stop this thread so that I can attach the debugger to see what’s going on
I forgot to add this UI thread was created before I created the CMainFrame Window however in the past I was able to have an AfxMessageBox in the CWinApp constructor and it worked
Thanks

modified 6-Dec-18 10:10am.

Victor Nijegorodov6-Dec-18 5:22

Victor Nijegorodov

6-Dec-18 5:22

Why are you using AfxMessageBox in a secondary thread? Confused | :confused:

ForNow6-Dec-18 5:26

6-Dec-18 5:26

Will use Message box establish my main window before thread creation and will move the CFrameWnd ::m_hWnd to UI thread window thanks

Victor Nijegorodov6-Dec-18 8:45

Victor Nijegorodov

6-Dec-18 8:45

It is not a good design to display a messagebox form any secondary thread.
Better would be PostMessage a user defined message to the main GUI thread with the parameters that you want to be displayed and let the main thread display it.

ForNow6-Dec-18 8:49

Keyboard functionality for IExplorerBrowser

6-Dec-18 8:49

This is just to debug a scenario that only happen in release I have to have a way of stopping the thread in release and attaching the debugger if there is a better way please share thanks

_Flaviu5-Dec-18 20:59

_Flaviu

5-Dec-18 20:59

How can I get all keyboard functionality for IExplorerBrowser[^] in a MFC app ? I have context menu options available for mouse, but not for keyboard (Ctrl+C, Ctrl+V, Ctrl+A, etc.). Is there any method to have these commands in my app ? I am pretty sure that is possible, but I don't know how Smile | :)

modified 6-Dec-18 3:47am.

Found Api's Causing Heap Corruption

ForNow5-Dec-18 2:23

5-Dec-18 2:23

These lines in My DrawItem Api are causing the heap corruption

C++

if(arrayptr[pdi->itemID] == NULL)
	        arrayptr[pdi->itemID] = new char(9);
	memset(arrayptr[pdi->itemID], 0x00, 9);
	memcpy(arrayptr[pdi->itemID], lpszText, 8);

Don't understand it as I allocated everything on the Heap

CPallini5-Dec-18 3:08

CPallini

5-Dec-18 3:08

Quote:
arrayptr[pdi->itemID] = new char(9);

Should be

C++

arrayptr[pdi->itemID] = new char[9];

ForNow5-Dec-18 3:11

Re: Found Api's Causing Heap Corruption CPallini You are Great thanks

5-Dec-18 3:11

WOW thanks good catch I didn't see however where the storage was initialized to 9 let me try

thanks

ForNow5-Dec-18 3:40

Re: Found Api's Causing Heap Corruption CPallini You are Great thanks

5-Dec-18 3:40

thanks

CPallini5-Dec-18 6:50

CPallini

5-Dec-18 6:50

You are welcome.
Did you really need to use raw (C-like) arrays and new?

Re: Found Api's Causing Heap Corruption CPallini You are Great thanks

ForNow5-Dec-18 7:28

5-Dec-18 7:28

I am MainFrame programmer by trade wasn't sure how to copy the first 8 characters of the 45 character strings

Thanks

Richard MacCutchan5-Dec-18 7:43

5-Dec-18 7:43

I missed that twice in the original thread below. Well spotted.

CComboBox list Appears After Trying to Close out Dialog

CPallini5-Dec-18 7:49

CPallini

5-Dec-18 7:49

Thank you, Richard. Smile | :)

ForNow4-Dec-18 16:06

Re: CComboBox list Appears After Trying to Close out Dialog

4-Dec-18 16:06

Hi
I Decided to start a new thread because for a moment I thought I had fixed my problem of the Disappearing list with the following code

I added a point to an array pointer for the strings I wanted to add

C++

class Casidcombo :	public CComboBox
{
	DECLARE_DYNAMIC(Casidcombo)
	private:
		int cright, cbottom, ctop;

public:
	Casidcombo();
	~Casidcombo();
	char **arrayptr;
protected:
	
	virtual void MeasureItem(LPMEASUREITEMSTRUCT lpMeasureItemStruct);
	virtual void DrawItem(LPDRAWITEMSTRUCT pdi);
	virtual int CompareItem(LPCOMPAREITEMSTRUCT lpCompareItemStruct);
	virtual void DeleteItem(LPDELETEITEMSTRUCT lpDeleteItemStruct);
	DECLARE_MESSAGE_MAP()
};

its the arrayptr not knowing exactly how may entries I would have I initialize it in the
OnInitDialogBox of the the Hosting Dialog

C++

m_Simple.arrayptr = new char *[j+1];
	for (int i = 0; i < j + 1; i++)
		m_Simple.arrayptr[i] = NULL;

In the DrawItem For The Combobox I copy of over part of the string

C++

if(arrayptr[pdi->itemID] == NULL)
	        arrayptr[pdi->itemID] = new char(9);
	memset(arrayptr[pdi->itemID], 0x00, 9);
	memcpy(arrayptr[pdi->itemID], lpszText, 8);

I then write it out

C++

dc.DrawText(
		arrayptr[pdi->itemID],
		8,
	    &pdi->rcItem,
		DT_CENTER | DT_SINGLELINE | DT_VCENTER);

The list now re-appears After I try closing out the Dialog by clicking on the 'X'
in the right hand Corner

I guess this drives the DrawItem function

My question is after appearing and disappearing initially (the list) of the ComboBox the vertical scroll bar is missing as well until I clisk on the 'X' in the right hand corner after which everything re-appears I guess that most Drive DrawItem I am still Baffled Why initially it disappears along with the scroll bar

This the last piece of code in the OnInitDialog

C++

ShowWindow(SW_SHOW);
	ShowWindow(SW_SHOW);

		return TRUE;

This is my message map I only have a Measure Item Message
BEGIN_MESSAGE_MAP(Casidcombo, CComboBox)
		ON_WM_MEASUREITEM()
	    	END_MESSAGE_MAP()

modified 4-Dec-18 22:16pm.

Richard MacCutchan4-Dec-18 22:13

Re: CComboBox list Appears After Trying to Close out Dialog

4-Dec-18 22:13

I have used user drawn ListView controls without problem in the past. I notice that you are using a CDC to draw the text in the view rather than responding to the notification messages and returning the relevant data. However, my sample does not use MFC so I may well be on the wrong track.

ForNow5-Dec-18 2:09

Re: CComboBox list Appears After Trying to Close out Dialog

5-Dec-18 2:09

Richard there are two api in DrawItem that are not supported in Native Win32 FillSolidRect only thing close is FillRect which takes a brush

Regardless I was getting a heap corruption so I ran my code in debug with the following

C++

//	InitCommonControlsEx(&InitCtrls);
#if _DEBUG
	afxMemDF = allocMemDF | checkAlwaysMemDF;
#endif

and at exiting DrawItem got the following

C++

#if defined _NO_CRT_STDIO_INLINE
;
#else
{
    int const _Result = __stdio_common_vsnprintf_s(
        _CRT_INTERNAL_LOCAL_PRINTF_OPTIONS,
        _Buffer, _BufferCount, _MaxCount, _Format, _Locale, _ArgList);

    return _Result < 0 ? -1 : _Result;
}
#endif

Exiting DrawItem I am getting a heap corruption

Richard MacCutchan5-Dec-18 2:41

Re: CComboBox list Appears After Trying to Close out Dialog

5-Dec-18 2:41

You need to actually trace the code to see where the heap is getting corrupted. It is usually caused by writing too many bytes into an allocated buffer. Notice that __stdio_common_vsnprintf_s takes two values which indicate the length, so one of them could be wrong.

ForNow5-Dec-18 2:50

Re: CComboBox list Appears After Trying to Close out Dialog

5-Dec-18 2:50

I Did but I don't understand why

I am getting a list of Addreess Spaces information from z/os I only want to Add the the list box the Job Name. Asid information is 45 bytes the first 8 is the JobName. So the First would be *Master*

I moved the code which copies the first 8 charcates from CComboBox::DrawItem to the DialogBox

just got Debug Assert on the AddString I think I am doing everything right;

C++

m_Simple.arrayptr = new char *[j+1];
	traverse = instr;
	for (int i = 0; i < j + 1; i++)
	{
		m_Simple.arrayptr[i] = new char(9);
		memset(m_Simple.arrayptr[i], 0x00, 9);
		memcpy(m_Simple.arrayptr[i], traverse, 8);
		m_Simple.AddString(m_Simple.arrayptr[i]);
		traverse = (char *)traverse + 45;
	}

The twisted Arrow after the Debug Heap Assertion is pointing to

C++

traverse = (char *)traverse + 45

So I guess there is a problem with AddString

Not sure what I am doing wrong

Richard MacCutchan5-Dec-18 7:36