Restrict InvalidateRect - C / C++ / MFC Discussion Boards

Re: Does "delete" operator work for PVOID pointers?

C^hris L^osinger21-Jul-11 5:01

21-Jul-11 5:01

this seems like a good place for an abstract base class with a virtual destructor and a derived class for each of the types you want to pass around.

or, you could do it with a simple struct:

struct cMyStruct
{
typedef enum {eInt=0, eDouble, eCreateStruct, ePaintStruct} eTypeID;
void *pData;
eTypeID typeID;

 cleanUp()
 {
   switch (typeID)
   {
       case eInt:
       {
          int *p = (int *)pData;
          delete p;
          pData = NULL;
       }
       break;
       etc...
   }
 }
};

just pass that around, initialized properly, of course.

image processing toolkits | batch image processing

Re: Does "delete" operator work for PVOID pointers?

David Crow21-Jul-11 5:11

David Crow

21-Jul-11 5:11

Cold_Fearing_Bird wrote:
Because the object is dynamically allocated, I cannot determine its exact type.

So the items in the listview "point to" different types of data? If that's the case, wrap the data and the type in a struct like:

struct data_and_type
{
    int type; // 0=CREATESTRUCT, 1=PAINTSTRUCT
    PVOID data;
};
  
data_and_type *dt = new data_and_type;
dt->type = 0;
dt->data = (CREATESTRUCT *) new CREATESTRUCT;
  
SetItemData(..., (DWORD) dt);

Now when you are ready to delete:

dt = (data_and_type *) GetItemData();
if (dt->type == 0)
{
    CREATESTRUCT *cs = (CREATESTRUCT *) dt->data;
    delete cs;
}
else if (dt->type == 1)
...

Clear as mud?

"One man's wage rise is another man's price increase." - Harold Wilson

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

"Some people are making such thorough preparation for rainy days that they aren't enjoying today's sunshine." - William Feather

Re: Does "delete" operator work for PVOID pointers?

Richard Andrew x6421-Jul-11 5:31

Richard Andrew x64

21-Jul-11 5:31

DavidCrow wrote:
dt->data = (CREATESTRUCT *) new CREATESTRUCT;

Any particular reason for the explicit cast?

The difficult we do right away...
...the impossible takes slightly longer.

Re: Does "delete" operator work for PVOID pointers?

David Crow21-Jul-11 6:16

David Crow

21-Jul-11 6:16

Richard Andrew x64 wrote:
Any particular reason for the explicit cast?

Yes. I had not typed enough this morning and was simply trying to meet my quota. Blush | :O

Re: Does "delete" operator work for PVOID pointers?

Stefan_Lang22-Jul-11 0:35

Stefan_Lang

22-Jul-11 0:35

Cold_Fearing_Bird wrote:
I new/malloc blocks

Are you sayiny you can't even tell what method you used to allocate memory? In that case you must make sure that you are calling the proper destruction method, i. e. either free() or delete (or, maybe delete [] ?). I fyou don't take care of that and use the wrong method, your program will crash at runtime.

Wherever you get the pointer from, you must add a release() method there that takes care of the proper destruction and deallocation. This most probably will involve virtual destructors in case of classes, or some other method of indirection.

Re: Does "delete" operator work for PVOID pointers?

C^hris L^osinger21-Jul-11 4:55

C^hris L^osinger

21-Jul-11 4:55

no
does that even compile?

image processing toolkits | batch image processing

Re: Does "delete" operator work for PVOID pointers?

Maximilien21-Jul-11 5:03

Maximilien

21-Jul-11 5:03

it does compiles on VS2008.

Watched code never compiles.

Restrict InvalidateRect

manju 321-Jul-11 2:12

manju 3

21-Jul-11 2:12

Hi all,

I have one parent dialog where in OnPaint Function i am drawing some rectangles.

On that dialog i am opening one more child dialog,
I am making that child dialog as modeless,so that i can move that dialog
I want to keep the modless dialog active even when i click on the parent dialog,so that i can move rectangles.

OnLButtonDown i need to redraw the rectangles and even keep the dialog visible.

But when i click the Mouse LButtonDown,my child dialog is getting dissappeared

void Test::OnLButtonDown(UINT nFlags, CPoint point)
{
	CRect rcClient(170,414,170,415);
	LeafDialog::GetClientRect(&rcClient);
  
	if((xp<415 && xp >140) && (yp>100))
	{
		InvalidateRect(rcClient,false);	// to force(Refresh) OnPaint to redraw
                     	LeafB[0]=100;
	   	LaefA[0] = 100;
	}
}

On Test View i am creating dialog

void CTestView::OnLoadImage() 
{
    CBitmapimage* dlgbmp;
    dlgbmp = new CBitmapimage;
    dlgbmp->Create(IDD_DIALOG1,this);
    dlgbmp->ShowWindow(SW_SHOW);
}

Can anyone tell me what can i do so that even i can move the image and redraw on the parent dialog when clicked on the rectangle

Thanks
Sharan

Re: Restrict InvalidateRect

Roger Allen26-Jul-11 6:28

Roger Allen

26-Jul-11 6:28

It sounds like the modless child dialog needs to have the HWND_TOPMOST position in the tab order so it never gets to go behind its parent window.

See the SetWindowPos function for details. You may have to be careful in its use as the modless window should not sit in top most mode when you application does not have focus.

If you vote me down, my score will only get lower

How to use "UnitTest" to test C++ code [modified]

Cold_Fearing_Bird20-Jul-11 21:49

Cold_Fearing_Bird

20-Jul-11 21:49

"UnitTest" is on the VC's main menu,I want to use itto test my C++ code, but I am not familiar with its mechanism.
I wrote a little code expecting to learn how it works.But seems not work.
here's my code

class myClass
{
private:
	int m_i ;
public:
	myClass( int i ):m_i(i){ }
	BOOL EQ( int i )
	{
		if( m_i == i )
			return TRUE ;
		else 
			return FALSE ;
	}
} ;

int main()
{
	myClass mc( 10 ) ;
}

I click "new UnitTest", go through a few steps,when trying click the checkbox besides my project name, there's always a msg reporting unsuccessful "Unknown virtual address 0".

Waiting for help...

modified on Thursday, July 21, 2011 5:09 AM

Re: How to use "UnitTest" to test C++ code

_AnsHUMAN_ 21-Jul-11 1:28

_AnsHUMAN_

21-Jul-11 1:28

I haven't used the tool myself, but isn't there a startup guide to make us understanding the procedure to be followed.
Also, you can refer the articles on MSDN and I sure you will find more than one that will guide you further.

You talk about Being HUMAN. I have it in my name
AnsHUMAN

Re: How to use "UnitTest" to test C++ code

Stefan_Lang21-Jul-11 1:57

Stefan_Lang

21-Jul-11 1:57

Certainly good advice, but I have to say it may not be easy to find useful material: I've faced almost the same problem, and my searches turned up tons of Tools for Unit-Testing or Tutorials for using such tools, but virtually nothing about how to set up a unit test in the first place! Frown | :(

Maybe an explicit search at specific sites such as MSDN or various technical forums might help - I haven't tried that yet.

Re: How to use "UnitTest" to test C++ code

Cold_Fearing_Bird21-Jul-11 2:33

Cold_Fearing_Bird

21-Jul-11 2:33

Yeah, I searched lot, still haven't found too much helpful materials.I think I should give up using it since it related tightly with netFramework.Someone says C++ test is one of the best UnitTest tool, I'll have a try.

Re: How to use "UnitTest" to test C++ code

Stefan_Lang21-Jul-11 2:55

Stefan_Lang

21-Jul-11 2:55

Indeed. I've been spending the last hour to find something more useful, and have all but given up. At the moment I'm digesting the entries on Unit testing that I've found on Wikipedia, just to be make sure I fully understand the concepts. Maybe that's a good place for you to look too?

Unit Testing - Wikipedia

Re: How to use "UnitTest" to test C++ code

Cold_Fearing_Bird21-Jul-11 4:45

Cold_Fearing_Bird

21-Jul-11 4:45

Thanks, Stefan. I'll take a look.I love Wiki too. It was the place that taught me how to do the matrix multiplication.Hoho Smile | :)

Re: How to use "UnitTest" to test C++ code

Rolf Kristensen27-Jul-11 12:18

Rolf Kristensen

27-Jul-11 12:18

This might help: Unit-Testing Native C++ with Visual Studio[^]

By using the Unit Testing framework in Visual Studio, then you should automatically get the ability to see code coverage (Though it requires one of the expensive Visual Studio Editions)

Long Strings in ComboBox not fully visible.

Le@rner20-Jul-11 18:21

Le@rner

20-Jul-11 18:21

Hi all,

i am using a droplist type combobox.i am inserted some strings in this combobox,but some long strings in combobox not fully visible.

it there any method to make visible these strings.

thanks in advance.

Re: Long Strings in ComboBox not fully visible.

Chandrasekharan P20-Jul-11 18:55

Chandrasekharan P

20-Jul-11 18:55

what does it mean not visible??

Try this link

http://weseetips.com/tag/change-combobox-dropdown-width/[^]

Re: Long Strings in ComboBox not fully visible.

Le@rner20-Jul-11 23:43

Le@rner

20-Jul-11 23:43

thanks

Re: Long Strings in ComboBox not fully visible.

_Flaviu24-Jul-11 7:08

_Flaviu

24-Jul-11 7:08

You can try Extended CComboBox[^] control ...

Print command to printer using PostMessage?

AnayKulkarni20-Jul-11 2:29

AnayKulkarni

20-Jul-11 2:29

Hello to all,
I have written a VC++(MFC) application in which one of our USB connectivity device gets connected to computer and I continuously collect the data from that device. I display that data on screen and also when I give print command to printer through my application then that data gets printed on paper.

Now my problem is that, when I give print command to printer then it interrupts or stops data collection from the device untill the printing process gets completed but due to this we loose data from the device. So is there any way to handle printing process independently? Means can we give print command to printer using "PostMessage" or using seperate thread so that it will not stop data collection from device? or is there any other way to do this?

This is really very very urgent so please please help me out.

Thanks and Regards

Anay

Re: Print command to printer using PostMessage?

Richard MacCutchan20-Jul-11 2:33

Richard MacCutchan

20-Jul-11 2:33

I would suggest using threads or even a separate program to do the printing. A lot depends on where you are storing the data that you are collecting.

The best things in life are not things.

CTabCtrl - retrieving tab's title text

rp_suman20-Jul-11 1:11

rp_suman

20-Jul-11 1:11

How to get the title text CTabCtrl's tabs?
The following code is crashing at the last line:

TCITEM tcItem;<br />
tcItem.mask = TCIF_TEXT;<br />
m_ReportTabCtrl.GetItem(ID_PANE_FOUND, &tcItem);<br />
CString csText = tcItem.pszText;<br />

Thanks & Regards

--
"Programming is an art that fights back!"

Re: CTabCtrl - retrieving tab's title text

Richard MacCutchan20-Jul-11 1:32

Richard MacCutchan

20-Jul-11 1:32

You did not initialise your TCITEM structure properly; see the MSDN documentation here[^]. It would be better to check the return value from all Windows function calls rather than just assuming that they have succeeded.

The best things in life are not things.

Re: CTabCtrl - retrieving tab's title text

rp_suman20-Jul-11 2:23

rp_suman

20-Jul-11 2:23

Thanks, It is working after initializing all the required members tcItem.pszText and tcItem.cchTextMax along with tcItem.mask.

--
"Programming is an art that fights back!"

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.