asked on

ClistCtrl Sorting Header Refresh

I need to change ClistCtrl sorting headers from time to time
I tried to:

1. SetRedraw(FALSE)
2. delete sorting headers
3. put new sorting headers
3. SetRedraw(TRUE)

Problem: I allways see headers being deleted
and drawn back again, How to hide these refresh????

but I still see

ASKER CERTIFIED SOLUTION

piano_boxer

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piano_boxer

I forgot this:
In order to handle the WM_MY_MESSAGE message, and this line just above END_MESSAGE_MAP() in the .cpp file:

ON_MESSAGE(WM_MY_MESSAGE, MyHandler)

and, add the declaration of the function to the class header

class MyClass...
{
...
LRESULT MyHandler(WPARAM, LPARAM);
....
};

tal031697

ASKER

Thanks.

LockWindowUpdate() did work!.
(I don't know why SetRedraw() didn't).

piano_boxer

One reason my be that SetRedraw() is supposed to be handled by the control by it self, and LockWindowUpdate() is handled internally by windows. (Windows queues up the WM_PAINT messages and sends them to the control when UnlockWindowUpdate() is called).

tal031697

ASKER

Well...
After I swapped SetRedraw() with LockWindowUpdate()
I remembered why I did try this once back, but Abandoned this
approach.

!!!CALLING UnlockWindowUpdate() REFRESHES THE WHOLE DESKTOP!!!!

so right now I'm back with SetRedraw() again.

I still need help,any other suggestions....?

piano_boxer

Hmmm, yes I'v seen this as well.

Here is a possible other solution:

Subclass the CListCtrl add a handler for the WM_PAINT message. Add a flag that determines if WM_PAINT messages are to be handled. Set this flag to false when you update the listctrl, and to true when done and call Invalidate() on the entire ListCtrl.

void CMyListCtrl::OnPaint(CDC* pDC)
{
if(m_bDoDraw)
{
CListCtrl::OnPaint(pDC);
}
}

tal031697

ASKER

Nop!, it didn't work.

even with the 'bDoDraw' flag I can sea the headers
being deleted and added.

... 8-(

piano_boxer

Could you post the code for 'delete sorting headers' and 'put new sorting headers' so that I can try some solutions?