場(chǎng)景在使用Win32/WTL虛擬列表時(shí)有時(shí)候底層短時(shí)間內(nèi)接收到批量的數(shù)據(jù)之后需要更新到列表。這時(shí)如果只用SetItemCount更新列表時(shí)更新的越頻繁列表就會(huì)越閃爍。這樣給用戶的體驗(yàn)就會(huì)比較差怎么解決閃爍的問題說(shuō)明虛擬列表[5]主要是用來(lái)大數(shù)據(jù)的顯示卡頓問題。 但現(xiàn)在使用SetItemCount增加行數(shù)時(shí)會(huì)頻繁刷新列表可見區(qū)域如果可見區(qū)域有自定義的圖片區(qū)域那么刷新圖片會(huì)有明顯的閃爍問題。 這個(gè)虛擬列表已經(jīng)有解決方案使用SetItemCountEx或者ListView_SetItemCountEx函數(shù)并傳遞LVSICF_NOINVALIDATEALL | LVSICF_NOSCROLL參數(shù)。LVSICF_NOINVALIDATEALL:除非受影響的項(xiàng)目當(dāng)前處于視圖中否則列表視圖控件不會(huì)重新繪出。 即當(dāng)前通過SetItemCountEx添加的行數(shù)剛好在列表的可見區(qū)域中,那么就會(huì)刷新。LVSICF_NOSCROLL: 當(dāng)項(xiàng)計(jì)數(shù)發(fā)生更改時(shí)列表視圖控件不會(huì)更改滾動(dòng)位置。 即當(dāng)前你滾動(dòng)到4-10行調(diào)用SetItemCountEx會(huì)影響當(dāng)前的列表可見的行數(shù)4-10行, 只會(huì)滑塊變小。因此項(xiàng)目中把SetItemCount替換為SetItemCountEx, 即不會(huì)閃爍也提供性能。listview_.SetItemCountEx(photos_.size(),LVSICF_NOINVALIDATEALL|LVSICF_NOSCROLL);listview_.SetItemCountEx(photos_.size(),LVSICF_NOINVALIDATEALL|LVSICF_NOSCROLL);例子View.h// View.h : interface of the CView class///////////////////////////////////////////////////////////////////////////////#pragmaonce#includeutility#includestring#includevector#includememory#includeatlmisc.h#includeatlctrls.h#includeatlctrlx.h#includeGdiPlus.husingnamespacestd;enum{kMyButtonIdWM_USER1,kMyButtonId2,kMyButtonId3,kMyListViewId};classPhoto{public:wstring name;wstring createDate;wstring path;wstring format;};classCView:publicCWindowImplCView{public:DECLARE_WND_CLASS(NULL)BOOLPreTranslateMessage(MSG*pMsg);BEGIN_MSG_MAP_EX(CView)MSG_WM_CREATE(OnCreate)MESSAGE_HANDLER(WM_PAINT,OnPaint)NOTIFY_HANDLER(kMyListViewId,NM_CLICK,OnNMClickListResult)NOTIFY_HANDLER(kMyListViewId,LVN_GETDISPINFO,OnGetListViewData)NOTIFY_HANDLER(kMyListViewId,LVN_ODCACHEHINT,OnPrepareListViewData)NOTIFY_HANDLER(kMyListViewId,LVN_ODFINDITEM,OnFindListViewData)COMMAND_RANGE_HANDLER_EX(kMyButtonId,kMyButtonId3,OnCommandIDHandlerEX)MSG_WM_TIMER(OnTimer)REFLECT_NOTIFICATIONS()END_MSG_MAP()protected:// Handler prototypes (uncomment arguments if needed):// LRESULT MessageHandler(UINT /*uMsg*/, WPARAM /*wParam*/, LPARAM /*lParam*/, BOOL /*bHandled*/)// LRESULT CommandHandler(WORD /*wNotifyCode*/, WORD /*wID*/, HWND /*hWndCtl*/, BOOL /*bHandled*/)// LRESULT NotifyHandler(int /*idCtrl*/, LPNMHDR /*pnmh*/, BOOL /*bHandled*/)intOnCreate(LPCREATESTRUCT lpCreateStruct);LRESULTOnPaint(UINT/*uMsg*/,WPARAM/*wParam*/,LPARAM/*lParam*/,BOOL/*bHandled*/);voidUpdateLayout();LRESULTOnNMClickListResult(intidCtrl,LPNMHDR pnmh,BOOLbHandled);LRESULTOnGetListViewData(intidCtrl,LPNMHDR pnmh,BOOLbHandled);LRESULTOnPrepareListViewData(intidCtrl,LPNMHDR pnmh,BOOLbHandled);LRESULTOnFindListViewData(intidCtrl,LPNMHDR pnmh,BOOLbHandled);voidOnCommandIDHandlerEX(UINT uNotifyCode,intnID,CWindow wndCtl);voidReloadMockData();voidReloadListView();voidOnTimer(UINT_PTR nIDEvent);private:std::wstringGetControlText(HWND hwnd,wchar_t*bufNULL);CListViewCtrl listview_;vectorshared_ptrPhoto*photos_;CFont font_normal_;CFont font_bold_;CBrushHandle brush_white_;CBrushHandle brush_hollow_;CBrush brush_red_;CButton buttonReloadMockData_;CButton buttonReloadListView_;CButton buttonDeleteListViewOneRow_;};View.cpp// View.cpp : implementation of the CView class///////////////////////////////////////////////////////////////////////////////#includestdafx.h#includeresource.h#includeutility#includesstream#includestdint.h#includeassert.h#includeStrsafe.h#includerandom#includeView.h#includeCommCtrl.h#includestring#includeregexusingnamespacestd;BOOLCView::PreTranslateMessage(MSG*pMsg){returnFALSE;}LRESULTCView::OnPaint(UINT/*uMsg*/,WPARAM/*wParam*/,LPARAM/*lParam*/,BOOL/*bHandled*/){CPaintDCdc(m_hWnd);CMemoryDCmdc(dc,dc.m_ps.rcPaint);CRect rect_client;GetClientRect(rect_client);mdc.FillSolidRect(rect_client,RGB(255,255,255));//TODO: Add your drawing code herereturn0;}staticHFONTGetFont(intpixel,boolbold,constwchar_t*font_name){LOGFONT lf;memset(lf,0,sizeof(LOGFONT));// zero out structurelf.lfHeightpixel;// request a 8-pixel-height fontif(bold){lf.lfWeightFW_BOLD;}lstrcpy(lf.lfFaceName,font_name);// request a face name ArialHFONT font::CreateFontIndirect(lf);returnfont;}std::wstringCView::GetControlText(HWND hwnd,wchar_t*buf){autolength::GetWindowTextLength(hwnd);boolbufNullfalse;if(!buf){bufnewwchar_t[length1]();bufNulltrue;}::GetWindowText(hwnd,buf,length1);std::wstringstr(buf);if(bufNull)delete[]buf;returnstr;}staticstd::wstringGetProductBinDir(){staticwchar_tszbuf[MAX_PATH];GetModuleFileName(NULL,szbuf,MAX_PATH);PathRemoveFileSpec(szbuf);intlengthlstrlen(szbuf);szbuf[length]L\\;szbuf[length1]0;returnstd::wstring(szbuf);}inttoRandInt(intmin,intmax){// thread_local 修飾符的變量只初始化一次,每個(gè)線程一個(gè)gen,避免多線程調(diào)用同一個(gè)gen導(dǎo)致數(shù)據(jù)競(jìng)爭(zhēng)。// 使用minstd_rand生成性能高簡(jiǎn)單的可預(yù)測(cè)的隨機(jī)數(shù)。// 使用mt19937 生成性能稍低很難預(yù)測(cè)的隨機(jī)數(shù)。//thread_local std::mt19937 gen(std::random_device{}());thread_localstd::minstd_randgen(std::random_device{}());std::uniform_int_distributiondist(min,max);returndist(gen);}LRESULTCView::OnGetListViewData(intidCtrl,LPNMHDR pnmh,BOOLbHandled){NMLVDISPINFO*plvdi(NMLVDISPINFO*)pnmh;autoiItemplvdi-item.iItem;if(-1iItem)return0;autocountphotos_.size();if(!count||countiItem)return0;autophotophotos_[iItem];if(plvdi-item.maskLVIF_TEXT){switch(plvdi-item.iSubItem){case0:{autovalueto_wstring((int64_t)iItem1);StringCchCopy(plvdi-item.pszText,plvdi-item.cchTextMax,value.c_str());break;}case1:{autovaluephoto-get()-nameL-to_wstring(toRandInt(1,100));StringCchCopy(plvdi-item.pszText,plvdi-item.cchTextMax,value.c_str());break;}case2:StringCchCopy(plvdi-item.pszText,plvdi-item.cchTextMax,photo-get()-format.c_str());break;case3:StringCchCopy(plvdi-item.pszText,plvdi-item.cchTextMax,photo-get()-createDate.c_str());break;}}return0;}LRESULTCView::OnPrepareListViewData(intidCtrl,LPNMHDR pnmh,BOOLbHandled){return0;}LRESULTCView::OnFindListViewData(intidCtrl,LPNMHDR pnmh,BOOLbHandled){LPNMLVFINDITEM pnmfi(LPNMLVFINDITEM)pnmh;autoiItempnmfi-iStart;if(-1iItem)return-1;autocountphotos_.size();if(!count||countiItem)return-1;return0;}LRESULTCView::OnNMClickListResult(intidCtrl,LPNMHDR pnmh,BOOLbHandled){return0;}voidCView::OnCommandIDHandlerEX(UINT uNotifyCode,intnID,CWindow wndCtl){switch(nID){casekMyButtonId:{ReloadMockData();break;}casekMyButtonId2:{ReloadListView();MessageBox(L刷新表格數(shù)據(jù)完成);break;}casekMyButtonId3:{std::vectorintrows;intiItem-1;while((iItemlistview_.GetNextItem(iItem,LVNI_SELECTED))!-1)rows.push_back(iItem);if(rows.empty())break;for(intirows.size()-1;i0;--i)photos_.erase(photos_.begin()rows.at(i));listview_.SetItemCountEx(photos_.size(),LVSICF_NOINVALIDATEALL|LVSICF_NOSCROLL);MessageBox(L已刪除);break;}}}voidCView::ReloadListView(){listview_.SetItemCount(0);for(autoi0;iphotos_.size();i)deletephotos_[i];photos_.clear();}voidCView::OnTimer(UINT_PTR nIDEvent){staticintconstkMaxCount200;staticintindex0;staticintcount0;if(countkMaxCount){count0;index0;KillTimer(nIDEvent);MessageBox(L刷新模擬數(shù)據(jù)完成);return;}wchar_tbuf[MAX_PATH]{0};LVCOLUMN co;memset(co,0,sizeof(co));co.maskLVCF_TEXT;co.pszTextbuf;co.cchTextMaxMAX_PATH;listview_.GetColumn(1,co);std::wstringc0Text(buf);listview_.GetColumn(2,co);std::wstringc1Text(buf);listview_.GetColumn(3,co);std::wstringc2Text(buf);for(inti0;i500countkMaxCount;i,index){autophotonewPhoto();wsprintf(buf,(c0TextL-%d).c_str(),index);photo-namebuf;wsprintf(buf,(c1TextL-%d).c_str(),index);photo-formatbuf;wsprintf(buf,(c2TextL-%d).c_str(),index);photo-createDatebuf;photos_.push_back(newshared_ptrPhoto(photo));}listview_.SetItemCountEx(photos_.size(),LVSICF_NOINVALIDATEALL|LVSICF_NOSCROLL);//listview_.SetItemCount(photos_.size());count;}voidCView::ReloadMockData(){SetTimer(1,500);}intCView::OnCreate(LPCREATESTRUCT lpCreateStruct){font_normal_::GetFont(16,false,LArial);font_bold_::GetFont(16,true,LArial);brush_hollow_AtlGetStockBrush(HOLLOW_BRUSH);brush_white_AtlGetStockBrush(WHITE_BRUSH);brush_red_.CreateSolidBrush(RGB(255,0,0));// 1.創(chuàng)建CListViewCtrllistview_.Create(m_hWnd,0,NULL,WS_CHILD|WS_TABSTOP|WS_VISIBLE|LVS_ALIGNLEFT|LVS_REPORT|LVS_SHOWSELALWAYS|WS_BORDER|LVS_OWNERDATA,0,kMyListViewId);listview_.SetExtendedListViewStyle(LVS_EX_FULLROWSELECT|LVS_EX_GRIDLINES|LVS_EX_DOUBLEBUFFER);//listview_.SetBkColor(RGB(255, 255, 255));listview_.SetTextBkColor(RGB(255,255,255));listview_.SetFont(font_normal_);autoheaderlistview_.GetHeader();header.SetFont(font_bold_);listview_.SetBkColor(RGB(255,255,255));listview_.InsertColumn(0,LNo.,LVCFMT_LEFT,100);listview_.InsertColumn(1,LName,LVCFMT_LEFT,100);listview_.InsertColumn(2,LFormat,LVCFMT_LEFT,100);listview_.InsertColumn(3,LCreate Date,LVCFMT_LEFT,100);// 2.創(chuàng)建按鈕buttonReloadMockData_.Create(m_hWnd,0,L加載新數(shù)據(jù),WS_CHILD|WS_VISIBLE,0,kMyButtonId);buttonReloadMockData_.SetFont(font_normal_);buttonReloadListView_.Create(m_hWnd,0,L刷新表格,WS_CHILD|WS_VISIBLE,0,kMyButtonId2);buttonReloadListView_.SetFont(font_normal_);buttonDeleteListViewOneRow_.Create(m_hWnd,0,L刪除選中行,WS_CHILD|WS_VISIBLE,0,kMyButtonId3);buttonDeleteListViewOneRow_.SetFont(font_normal_);UpdateLayout();return0;}voidCView::UpdateLayout(){CRect rect;GetClientRect(rect);CClientDCdc(m_hWnd);dc.SelectFont(font_normal_);CSizesize_control(500,300);CRect rect_controlCRect(CPoint(20,20),size_control);listview_.MoveWindow(rect_control);CSize size_button;buttonReloadMockData_.GetIdealSize(size_button);rect_controlCRect(CPoint(rect_control.left,rect_control.bottom10),size_button);buttonReloadMockData_.MoveWindow(rect_control);CSize sizeButton2;buttonReloadListView_.GetIdealSize(sizeButton2);rect_controlCRect(CPoint(rect_control.right10,rect_control.top),sizeButton2);buttonReloadListView_.MoveWindow(rect_control);CSize sizeButton3;buttonDeleteListViewOneRow_.GetIdealSize(sizeButton3);rect_controlCRect(CPoint(rect_control.right10,rect_control.top),sizeButton3);buttonDeleteListViewOneRow_.MoveWindow(rect_control);}項(xiàng)目項(xiàng)目源碼,VS2010以上 https://download.csdn.net/download/infoworld/93325545運(yùn)行帶SetItemCountEx帶LVSICF_NOINVALIDATEALL | LVSICF_NOSCROLL參數(shù):SetItemCount不帶參數(shù)不帶參數(shù)時(shí)當(dāng)前可見區(qū)域一直刷新這里Name一直變化就是說(shuō)明在插入數(shù)據(jù)時(shí)一直刷新參考LVM_GETNEXTITEMLVM_SETITEMCOUNTListView_SetItemCountListView_SetItemCountEx使用虛擬列表視圖來(lái)解決新增大量數(shù)據(jù)卡頓問題關(guān)于列表視圖控件