Re: CListView with checkbox problem

From:

"Victor" <nijegorodov.otpusk@freenet.de>

Newsgroups:

microsoft.public.vc.mfc

Date:

Wed, 18 Feb 2009 21:49:35 +0100

Message-ID:

<uyUhnpgkJHA.1340@TK2MSFTNGP06.phx.gbl>

Wrong!
You must not directly access main GUI thread controls form within another
thread. You could find some info about it in MSDN, and I guess, Joe will
explain you this problem with more details. :)
Read Joe's essay about using worker threads:
http://www.flounder.com/workerthreads.htm

Victor

"97612" <97612@discussions.microsoft.com> wrote in message
news:84452368-983D-4E10-8290-3689408B0773@microsoft.com...

//*********** code *************//
unsigned long _stdcall RunLoadThumbnailThread( LPVOID lpParam )
{
int nIndex = 0;
std::vector<CString>::iterator iter;

CThumbView *pView = (CThumbView*)lpParam;
CePhotoSyncDoc *pDoc = (CePhotoSyncDoc*)pView->GetDocument();

CListCtrl& ListCtrl = pView->GetListCtrl();
CImageList *pImgList = &pView->m_ImageListThumb;

int iImageCount = pImgList->GetImageCount();

for( int i=0; i < iImageCount; i++ )
{
pImgList->Remove(i);
}

ListCtrl.DeleteAllItems();
pImgList->SetImageCount( pDoc->m_vFileName.size() );

ListCtrl.SetRedraw( FALSE );

for( iter = pDoc->m_vFileName.begin();
iter != pDoc->m_vFileName.end() && pView->m_bTerminate != TRUE;
iter++, nIndex++ )
{
  HBITMAP hbmReturn = NULL;
  Bitmap *bmPhoto = NULL;
   CBitmap Bmp1;

  ListCtrl.InsertItem( nIndex, *iter, nIndex );

  CString path; path.Empty();
  path.Format( _T("%s\\%s"), pDoc->m_strCurrentDirectory, *iter);

  Bitmap image( path.AllocSysString() );

  int sourceWidth = image.GetWidth();
  int sourceHeight = image.GetHeight();

  int destX = 0, destY = 0;

  float nPercent = 0;
  float nPercentW = ((float)THUMBNAIL_WIDTH/(float)sourceWidth);;
  float nPercentH = ((float)THUMBNAIL_HEIGHT/(float)sourceHeight);

  if(nPercentH < nPercentW)
  {
  nPercent = nPercentH;
  destX = (int)((THUMBNAIL_WIDTH - (sourceWidth * nPercent))/2);
  }
  else
  {
  nPercent = nPercentW;
  destY = (int)((THUMBNAIL_HEIGHT - (sourceHeight * nPercent))/2);
  }

  int destWidth = (int)(sourceWidth * nPercent);
  int destHeight = (int)(sourceHeight * nPercent);

  bmPhoto = new Bitmap( THUMBNAIL_WIDTH, THUMBNAIL_HEIGHT,
PixelFormat24bppRGB );
  bmPhoto->SetResolution( image.GetHorizontalResolution(),
image.GetVerticalResolution() );

  Graphics *grPhoto = Graphics::FromImage( bmPhoto );
  Color colorW(255, 255, 255, 255);
  grPhoto->Clear( colorW );
  grPhoto->SetInterpolationMode( InterpolationModeHighQualityBicubic );
  grPhoto->DrawImage( &image, Rect(destX, destY, destWidth, destHeight) );

  bmPhoto->GetHBITMAP( colorW, &hbmReturn );

  Bmp1.Attach( hbmReturn );
  pImgList->Replace( nIndex, &Bmp1, NULL );

  delete grPhoto;
  delete bmPhoto;
  Bmp1.Detach();
  DeleteObject( hbmReturn );
}

ListCtrl.SetRedraw(TRUE);
ListCtrl.Invalidate();

pView->m_bRunning = FALSE;
pView->m_bTerminate = FALSE;

pView->m_hThreadLoad = NULL;
::CloseHandle( pView->m_hThreadLoad );

return 0;
}
//*********** code *************//

Above is the code I got from the Internet, run as a thread.

I don't really know the icon you mentioned, can you explain more for me?

Thanks.

"Tom Serface" wrote:

How are you setting up your bitmaps? Are you thinking your bitmap *is*
the icon?

Tom

"97612" <97612@discussions.microsoft.com> wrote in message
news:D80A4D57-F38E-4E3B-8561-254D852B9EE9@microsoft.com...

I got another problem. When I click a thumbnail image, the
"hitinfo.flags != LVHT_ONITEMSTATEICON" still true, and the program
returned. I don't know if I use the wrong way?

Below is my source code:
void CThumbView::OnLvnItemchanged(NMHDR *pNMHDR, LRESULT *pResult)
{
LPNMLISTVIEW pNMLV = reinterpret_cast<LPNMLISTVIEW>(pNMHDR);
// TODO: Add your control notification handler code here
CListCtrl& ListCtrl = GetListCtrl();
LVHITTESTINFO hitinfo;
*pResult = 0;

//Copy click point
hitinfo.pt = pNMLV->ptAction;

//Make the hit test...
int nItem = ListCtrl.HitTest(&hitinfo);
//No click on image item, return
if(hitinfo.flags != LVHT_ONITEMSTATEICON)
return;

//Image item hit
CePhotoSyncDoc* pDoc = (CePhotoSyncDoc*)GetDocument();
ASSERT_VALID(pDoc);
pDoc->SelectItem( pNMLV->iItem );
pDoc->UpdateAllViews(this, UPDATE_PREVIEW);
}

"97612" wrote:

Thanks for your help, it works.

Thanks a lot.

"Tom Serface" wrote:

You could check if the user clicked on the state icon:

NMLISTVIEW* pNMListView = (NM_LISTVIEW*)pNMHDR;
LVHITTESTINFO hitinfo;
*pResult = 0;

//Copy click point
hitinfo.pt = pNMListView->ptAction;

//Make the hit test...
int nItem = m_cList.HitTest(&hitinfo);

if(hitinfo.flags != LVHT_ONITEMSTATEICON)
return; // Didn't click on an icon

Tom

"97612" <97612@discussions.microsoft.com> wrote in message
news:5FA84CE6-E121-4AE9-8AC8-C3D3C6B6A0D3@microsoft.com...

I use CListView to draw the thumbnail of a image list. And I want
to
add
the
checkbox for the image list. When I select a thumbnail, the
CListView
will
trigger the "OnLvnItemchanged" event to let another view to show
the
preview
image of the selected image.
My problem is that when I use
"ListCtrl.SetExtendedStyle(ListCtrl.GetStyle()|LVS_EX_CHECKBOXES )",
the
"OnLvnItemchanged" is trigger by the initial operation for
checkbox.
This
is
not I expected, how can I solve the problem?

Thanks for your help.