带复选框的下拉列表

MAKELONG(GetWindowLong(m_pComboBox->m_hWnd, GWL_ID), CBN_SELCHANGE), (LPARAM)m_pComboBox->m_hWnd); } #endif break; }

// Make the combobox always return -1 as the current selection. This // causes the lpDrawItemStruct->itemID in DrawItem() to be -1 // when the always-visible-portion of the combo is drawn case LB_GETCURSEL: { return -1; }

case WM_CHAR: {

if (wParam == VK_SPACE) { // Get the current selection INT nIndex = CallWindowProcA(m_pWndProc, hWnd, LB_GETCURSEL, wParam, lParam); CRect rcItem;

SendMessage(hWnd, LB_GETITEMRECT, nIndex, (LONG)(VOID *)&rcItem); InvalidateRect(hWnd, rcItem, FALSE);

// Invert the check mark

m_pComboBox->SetCheck(nIndex, !m_pComboBox->GetCheck(nIndex)); // Notify that selection has changed

m_pComboBox->GetParent()->SendMessage(WM_COMMAND,

MAKELONG(GetWindowLong(m_pComboBox->m_hWnd, GWL_ID), CBN_SELCHANGE), (LPARAM)m_pComboBox->m_hWnd); return 0; } break; }

case WM_LBUTTONDOWN: {

CRect rcClient;

GetClientRect(hWnd, rcClient);

CPoint pt;

pt.x = LOWORD(lParam); pt.y = HIWORD(lParam);

if (PtInRect(rcClient, pt)) {

INT nItemHeight = SendMessage(hWnd, LB_GETITEMHEIGHT, 0, 0); INT nTopIndex = SendMessage(hWnd, LB_GETTOPINDEX, 0, 0); // Compute which index to check/uncheck

INT nIndex = nTopIndex + pt.y / nItemHeight;

CRect rcItem;

SendMessage(hWnd, LB_GETITEMRECT, nIndex, (LONG)(VOID *)&rcItem); if (PtInRect(rcItem, pt)) { // Invalidate this window

InvalidateRect(hWnd, rcItem, FALSE);

m_pComboBox->SetCheck(nIndex, !m_pComboBox->GetCheck(nIndex)); // Notify that selection has changed

m_pComboBox->GetParent()->SendMessage(WM_COMMAND,

MAKELONG(GetWindowLong(m_pComboBox->m_hWnd, GWL_ID), CBN_SELCHANGE), (LPARAM)m_pComboBox->m_hWnd);

} }

// Do the default handling now (such as close the popup // window when clicked outside) break; }

case WM_LBUTTONUP: {

// Don't do anything here. This causes the combobox popup // windows to remain open after a selection has been made return 0; } }

return CallWindowProc(m_pWndProc, hWnd, nMsg, wParam, lParam); }

CCheckComboBox::CCheckComboBox() {

m_hListBox = 0; m_bTextUpdated = FALSE; m_bItemHeightSet = FALSE; }

CCheckComboBox::~CCheckComboBox() { }

BOOL CCheckComboBox::Create(DWORD dwStyle, const RECT& rect, CWnd* pParentWnd, UINT nID) {

// Remove the CBS_SIMPLE and CBS_DROPDOWN styles and add the one I'm designed for dwStyle &= ~0xF;

dwStyle |= CBS_DROPDOWNLIST;

// Make sure to use the CBS_OWNERDRAWVARIABLE style dwStyle |= CBS_OWNERDRAWVARIABLE;

// Use default strings. We need the itemdata to store checkmarks dwStyle |= CBS_HASSTRINGS;

return CComboBox::Create(dwStyle, rect, pParentWnd, nID); }

LRESULT CCheckComboBox::OnCtlColorListBox(WPARAM wParam, LPARAM lParam) {

// If the listbox hasn't been subclassed yet, do so... if (m_hListBox == 0) {

HWND hWnd = (HWND)lParam;

if (hWnd != 0 && hWnd != m_hWnd) { // Save the listbox handle m_hListBox = hWnd;

// Do the subclassing

m_pWndProc = (WNDPROC)GetWindowLong(m_hListBox, GWL_WNDPROC);

SetWindowLong(m_hListBox, GWL_WNDPROC, (LONG)ComboBoxListBoxProc);

} }

return DefWindowProc(WM_CTLCOLORLISTBOX, wParam, lParam); }

void CCheckComboBox::DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct) {

HDC dc = lpDrawItemStruct->hDC;

CRect rcBitmap = lpDrawItemStruct->rcItem; CRect rcText = lpDrawItemStruct->rcItem; CString strText;

// 0 - No check, 1 - Empty check, 2 - Checked INT nCheck = 0;

// Check if we are drawing the static portion of the combobox if ((LONG)lpDrawItemStruct->itemID < 0) {

// Make sure the m_strText member is updated RecalcText(); // Get the text

strText = m_strText;

// Don't draw any boxes on this item nCheck = 0; }

// Otherwise it is one of the items else {

GetLBText(lpDrawItemStruct->itemID, strText);

nCheck = 1 + (GetItemData(lpDrawItemStruct->itemID) != 0); TEXTMETRIC metrics;

GetTextMetrics(dc, &metrics);

rcBitmap.left = 0;

rcBitmap.right = rcBitmap.left + metrics.tmHeight + metrics.tmExternalLeading + 6; rcBitmap.top += 1; rcBitmap.bottom -= 1;