src/msw/listbox.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/msw/listbox.cpp
   3 // Purpose:     wxListBox
   4 // Author:      Julian Smart
   5 // Modified by: Vadim Zeitlin (owner drawn stuff)
   6 // Created:
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Julian Smart
   9 // Licence:     wxWindows license
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 #ifdef __GNUG__
  13     #pragma implementation "listbox.h"
  14 #endif
  15
  16 // For compilers that support precompilation, includes "wx.h".
  17 #include "wx/wxprec.h"
  18
  19 #ifdef __BORLANDC__
  20     #pragma hdrstop
  21 #endif
  22
  23 #if wxUSE_LISTBOX
  24
  25 #ifndef WX_PRECOMP
  26 #include "wx/listbox.h"
  27 #include "wx/settings.h"
  28 #include "wx/brush.h"
  29 #include "wx/font.h"
  30 #include "wx/dc.h"
  31 #include "wx/utils.h"
  32 #endif
  33
  34 #include "wx/window.h"
  35 #include "wx/msw/private.h"
  36
  37 #include <windowsx.h>
  38
  39 #include "wx/dynarray.h"
  40 #include "wx/log.h"
  41
  42 #if wxUSE_OWNER_DRAWN
  43     #include  "wx/ownerdrw.h"
  44 #endif
  45
  46 #ifndef __TWIN32__
  47     #ifdef __GNUWIN32_OLD__
  48         #include "wx/msw/gnuwin32/extra.h"
  49     #endif
  50 #endif
  51
  52     IMPLEMENT_DYNAMIC_CLASS(wxListBox, wxControl)
  53
  54 // ============================================================================
  55 // list box item declaration and implementation
  56 // ============================================================================
  57
  58 #if wxUSE_OWNER_DRAWN
  59
  60 class wxListBoxItem : public wxOwnerDrawn
  61 {
  62 public:
  63     wxListBoxItem(const wxString& str = wxEmptyString);
  64 };
  65
  66 wxListBoxItem::wxListBoxItem(const wxString& str) : wxOwnerDrawn(str, FALSE)
  67 {
  68     // no bitmaps/checkmarks
  69     SetMarginWidth(0);
  70 }
  71
  72 wxOwnerDrawn *wxListBox::CreateLboxItem(size_t WXUNUSED(n))
  73 {
  74     return new wxListBoxItem();
  75 }
  76
  77 #endif  //USE_OWNER_DRAWN
  78
  79 // ============================================================================
  80 // list box control implementation
  81 // ============================================================================
  82
  83 // ----------------------------------------------------------------------------
  84 // creation
  85 // ----------------------------------------------------------------------------
  86
  87 // Listbox item
  88 wxListBox::wxListBox()
  89 {
  90     m_noItems = 0;
  91     m_selected = 0;
  92 }
  93
  94 bool wxListBox::Create(wxWindow *parent,
  95                        wxWindowID id,
  96                        const wxPoint& pos,
  97                        const wxSize& size,
  98                        int n, const wxString choices[],
  99                        long style,
 100                        const wxValidator& validator,
 101                        const wxString& name)
 102 {
 103     m_noItems = 0;
 104     m_hWnd = 0;
 105     m_selected = 0;
 106
 107     SetName(name);
 108 #if wxUSE_VALIDATORS
 109     SetValidator(validator);
 110 #endif // wxUSE_VALIDATORS
 111
 112     if (parent)
 113         parent->AddChild(this);
 114
 115     SetBackgroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_WINDOW));
 116     SetForegroundColour(parent->GetForegroundColour());
 117
 118     m_windowId = ( id == -1 ) ? (int)NewControlId() : id;
 119
 120     int x = pos.x;
 121     int y = pos.y;
 122     int width = size.x;
 123     int height = size.y;
 124     m_windowStyle = style;
 125
 126     DWORD wstyle = WS_VISIBLE | WS_VSCROLL | WS_TABSTOP |
 127                    LBS_NOTIFY | LBS_HASSTRINGS /* | WS_CLIPSIBLINGS */;
 128
 129     wxASSERT_MSG( !(style & wxLB_MULTIPLE) || !(style & wxLB_EXTENDED),
 130                   _T("only one of listbox selection modes can be specified") );
 131
 132     if ( (m_windowStyle & wxBORDER_MASK) == wxBORDER_DEFAULT )
 133         m_windowStyle |= wxBORDER_SUNKEN;
 134
 135     if ( m_windowStyle & wxCLIP_SIBLINGS )
 136         wstyle |= WS_CLIPSIBLINGS;
 137
 138     if (m_windowStyle & wxLB_MULTIPLE)
 139         wstyle |= LBS_MULTIPLESEL;
 140     else if (m_windowStyle & wxLB_EXTENDED)
 141         wstyle |= LBS_EXTENDEDSEL;
 142
 143     if (m_windowStyle & wxLB_ALWAYS_SB)
 144         wstyle |= LBS_DISABLENOSCROLL;
 145     if (m_windowStyle & wxLB_HSCROLL)
 146         wstyle |= WS_HSCROLL;
 147     if (m_windowStyle & wxLB_SORT)
 148         wstyle |= LBS_SORT;
 149
 150 #if wxUSE_OWNER_DRAWN
 151     if ( m_windowStyle & wxLB_OWNERDRAW ) {
 152         // we don't support LBS_OWNERDRAWVARIABLE yet
 153         wstyle |= LBS_OWNERDRAWFIXED;
 154     }
 155 #endif
 156
 157     // Without this style, you get unexpected heights, so e.g. constraint layout
 158     // doesn't work properly
 159     wstyle |= LBS_NOINTEGRALHEIGHT;
 160
 161     bool want3D;
 162     WXDWORD exStyle = Determine3DEffects(WS_EX_CLIENTEDGE, &want3D);
 163
 164     // Even with extended styles, need to combine with WS_BORDER for them to
 165     // look right.
 166     if ( want3D || wxStyleHasBorder(m_windowStyle) )
 167     {
 168         wstyle |= WS_BORDER;
 169     }
 170
 171     m_hWnd = (WXHWND)::CreateWindowEx(exStyle, wxT("LISTBOX"), NULL,
 172             wstyle | WS_CHILD,
 173             0, 0, 0, 0,
 174             (HWND)parent->GetHWND(), (HMENU)m_windowId,
 175             wxGetInstance(), NULL);
 176
 177     wxCHECK_MSG( m_hWnd, FALSE, wxT("Failed to create listbox") );
 178
 179 #if wxUSE_CTL3D
 180     if (want3D)
 181     {
 182         Ctl3dSubclassCtl(GetHwnd());
 183         m_useCtl3D = TRUE;
 184     }
 185 #endif
 186
 187     // Subclass again to catch messages
 188     SubclassWin(m_hWnd);
 189
 190     size_t ui;
 191     for (ui = 0; ui < (size_t)n; ui++) {
 192         Append(choices[ui]);
 193     }
 194
 195     if ( (m_windowStyle & wxLB_MULTIPLE) == 0 )
 196         SendMessage(GetHwnd(), LB_SETCURSEL, 0, 0);
 197
 198     SetFont(parent->GetFont());
 199
 200     SetSize(x, y, width, height);
 201
 202     return TRUE;
 203 }
 204
 205 wxListBox::~wxListBox()
 206 {
 207     Free();
 208 }
 209
 210 void wxListBox::SetupColours()
 211 {
 212     SetBackgroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_WINDOW));
 213     SetForegroundColour(GetParent()->GetForegroundColour());
 214 }
 215
 216 // ----------------------------------------------------------------------------
 217 // implementation of wxListBoxBase methods
 218 // ----------------------------------------------------------------------------
 219
 220 void wxListBox::DoSetFirstItem(int N)
 221 {
 222     wxCHECK_RET( N >= 0 && N < m_noItems,
 223                  wxT("invalid index in wxListBox::SetFirstItem") );
 224
 225     SendMessage(GetHwnd(), LB_SETTOPINDEX, (WPARAM)N, (LPARAM)0);
 226 }
 227
 228 void wxListBox::Delete(int N)
 229 {
 230     wxCHECK_RET( N >= 0 && N < m_noItems,
 231                  wxT("invalid index in wxListBox::Delete") );
 232
 233     // for owner drawn objects, the data is used for storing wxOwnerDrawn
 234     // pointers and we shouldn't touch it
 235 #if !wxUSE_OWNER_DRAWN
 236     if ( !(m_windowStyle & wxLB_OWNERDRAW) )
 237 #endif // !wxUSE_OWNER_DRAWN
 238         if ( HasClientObjectData() )
 239         {
 240             delete GetClientObject(N);
 241         }
 242
 243     SendMessage(GetHwnd(), LB_DELETESTRING, N, 0);
 244     m_noItems--;
 245
 246     SetHorizontalExtent(wxEmptyString);
 247 }
 248
 249 int wxListBox::DoAppend(const wxString& item)
 250 {
 251     int index = ListBox_AddString(GetHwnd(), item);
 252     m_noItems++;
 253
 254 #if wxUSE_OWNER_DRAWN
 255     if ( m_windowStyle & wxLB_OWNERDRAW ) {
 256         wxOwnerDrawn *pNewItem = CreateLboxItem(index); // dummy argument
 257         pNewItem->SetName(item);
 258         m_aItems.Insert(pNewItem, index);
 259         ListBox_SetItemData(GetHwnd(), index, pNewItem);
 260         pNewItem->SetFont(GetFont());
 261     }
 262 #endif // wxUSE_OWNER_DRAWN
 263
 264     SetHorizontalExtent(item);
 265
 266     return index;
 267 }
 268
 269 void wxListBox::DoSetItems(const wxArrayString& choices, void** clientData)
 270 {
 271     // avoid flicker - but don't need to do this for a hidden listbox
 272     bool hideAndShow = IsShown();
 273     if ( hideAndShow )
 274     {
 275         ShowWindow(GetHwnd(), SW_HIDE);
 276     }
 277
 278     ListBox_ResetContent(GetHwnd());
 279
 280     m_noItems = choices.GetCount();
 281     int i;
 282     for (i = 0; i < m_noItems; i++)
 283     {
 284         ListBox_AddString(GetHwnd(), choices[i]);
 285         if ( clientData )
 286         {
 287             SetClientData(i, clientData[i]);
 288         }
 289     }
 290
 291 #if wxUSE_OWNER_DRAWN
 292     if ( m_windowStyle & wxLB_OWNERDRAW ) {
 293         // first delete old items
 294         WX_CLEAR_ARRAY(m_aItems);
 295
 296         // then create new ones
 297         for ( size_t ui = 0; ui < (size_t)m_noItems; ui++ ) {
 298             wxOwnerDrawn *pNewItem = CreateLboxItem(ui);
 299             pNewItem->SetName(choices[ui]);
 300             m_aItems.Add(pNewItem);
 301             ListBox_SetItemData(GetHwnd(), ui, pNewItem);
 302         }
 303     }
 304 #endif // wxUSE_OWNER_DRAWN
 305
 306     SetHorizontalExtent();
 307
 308     if ( hideAndShow )
 309     {
 310         // show the listbox back if we hid it
 311         ShowWindow(GetHwnd(), SW_SHOW);
 312     }
 313 }
 314
 315 int wxListBox::FindString(const wxString& s) const
 316 {
 317     int pos = ListBox_FindStringExact(GetHwnd(), (WPARAM)-1, s);
 318     if (pos == LB_ERR)
 319         return wxNOT_FOUND;
 320     else
 321         return pos;
 322 }
 323
 324 void wxListBox::Clear()
 325 {
 326     Free();
 327
 328     ListBox_ResetContent(GetHwnd());
 329
 330     m_noItems = 0;
 331     SetHorizontalExtent();
 332 }
 333
 334 void wxListBox::Free()
 335 {
 336 #if wxUSE_OWNER_DRAWN
 337     if ( m_windowStyle & wxLB_OWNERDRAW )
 338     {
 339         WX_CLEAR_ARRAY(m_aItems);
 340     }
 341     else
 342 #endif // wxUSE_OWNER_DRAWN
 343     if ( HasClientObjectData() )
 344     {
 345         for ( size_t n = 0; n < (size_t)m_noItems; n++ )
 346         {
 347             delete GetClientObject(n);
 348         }
 349     }
 350 }
 351
 352 void wxListBox::SetSelection(int N, bool select)
 353 {
 354     wxCHECK_RET( N >= 0 && N < m_noItems,
 355                  wxT("invalid index in wxListBox::SetSelection") );
 356
 357     if ( HasMultipleSelection() )
 358     {
 359         SendMessage(GetHwnd(), LB_SETSEL, select, N);
 360     }
 361     else
 362     {
 363         SendMessage(GetHwnd(), LB_SETCURSEL, select ? N : -1, 0);
 364     }
 365 }
 366
 367 bool wxListBox::IsSelected(int N) const
 368 {
 369     wxCHECK_MSG( N >= 0 && N < m_noItems, FALSE,
 370                  wxT("invalid index in wxListBox::Selected") );
 371
 372     return SendMessage(GetHwnd(), LB_GETSEL, N, 0) == 0 ? FALSE : TRUE;
 373 }
 374
 375 wxClientData* wxListBox::DoGetItemClientObject(int n) const
 376 {
 377     return (wxClientData *)DoGetItemClientData(n);
 378 }
 379
 380 void *wxListBox::DoGetItemClientData(int n) const
 381 {
 382     wxCHECK_MSG( n >= 0 && n < m_noItems, NULL,
 383                  wxT("invalid index in wxListBox::GetClientData") );
 384
 385     return (void *)SendMessage(GetHwnd(), LB_GETITEMDATA, n, 0);
 386 }
 387
 388 void wxListBox::DoSetItemClientObject(int n, wxClientData* clientData)
 389 {
 390     DoSetItemClientData(n, clientData);
 391 }
 392
 393 void wxListBox::DoSetItemClientData(int n, void *clientData)
 394 {
 395     wxCHECK_RET( n >= 0 && n < m_noItems,
 396                  wxT("invalid index in wxListBox::SetClientData") );
 397
 398 #if wxUSE_OWNER_DRAWN
 399     if ( m_windowStyle & wxLB_OWNERDRAW )
 400     {
 401         // client data must be pointer to wxOwnerDrawn, otherwise we would crash
 402         // in OnMeasure/OnDraw.
 403         wxFAIL_MSG(wxT("Can't use client data with owner-drawn listboxes"));
 404     }
 405 #endif // wxUSE_OWNER_DRAWN
 406
 407     if ( ListBox_SetItemData(GetHwnd(), n, clientData) == LB_ERR )
 408         wxLogDebug(wxT("LB_SETITEMDATA failed"));
 409 }
 410
 411 // Return number of selections and an array of selected integers
 412 int wxListBox::GetSelections(wxArrayInt& aSelections) const
 413 {
 414     aSelections.Empty();
 415
 416     if ( HasMultipleSelection() )
 417     {
 418         int countSel = ListBox_GetSelCount(GetHwnd());
 419         if ( countSel == LB_ERR )
 420         {
 421             wxLogDebug(_T("ListBox_GetSelCount failed"));
 422         }
 423         else if ( countSel != 0 )
 424         {
 425             int *selections = new int[countSel];
 426
 427             if ( ListBox_GetSelItems(GetHwnd(),
 428                                      countSel, selections) == LB_ERR )
 429             {
 430                 wxLogDebug(wxT("ListBox_GetSelItems failed"));
 431                 countSel = -1;
 432             }
 433             else
 434             {
 435                 aSelections.Alloc(countSel);
 436                 for ( int n = 0; n < countSel; n++ )
 437                     aSelections.Add(selections[n]);
 438             }
 439
 440             delete [] selections;
 441         }
 442
 443         return countSel;
 444     }
 445     else  // single-selection listbox
 446     {
 447         if (ListBox_GetCurSel(GetHwnd()) > -1)
 448             aSelections.Add(ListBox_GetCurSel(GetHwnd()));
 449
 450         return aSelections.Count();
 451     }
 452 }
 453
 454 // Get single selection, for single choice list items
 455 int wxListBox::GetSelection() const
 456 {
 457     wxCHECK_MSG( !HasMultipleSelection(),
 458                  -1,
 459                  wxT("GetSelection() can't be used with multiple-selection listboxes, use GetSelections() instead.") );
 460
 461     return ListBox_GetCurSel(GetHwnd());
 462 }
 463
 464 // Find string for position
 465 wxString wxListBox::GetString(int N) const
 466 {
 467     wxCHECK_MSG( N >= 0 && N < m_noItems, wxEmptyString,
 468                  wxT("invalid index in wxListBox::GetClientData") );
 469
 470     int len = ListBox_GetTextLen(GetHwnd(), N);
 471
 472     // +1 for terminating NUL
 473     wxString result;
 474     ListBox_GetText(GetHwnd(), N, result.GetWriteBuf(len + 1));
 475     result.UngetWriteBuf();
 476
 477     return result;
 478 }
 479
 480 void
 481 wxListBox::DoInsertItems(const wxArrayString& items, int pos)
 482 {
 483     wxCHECK_RET( pos >= 0 && pos <= m_noItems,
 484                  wxT("invalid index in wxListBox::InsertItems") );
 485
 486     int nItems = items.GetCount();
 487     for ( int i = 0; i < nItems; i++ )
 488     {
 489         int idx = ListBox_InsertString(GetHwnd(), i + pos, items[i]);
 490
 491 #if wxUSE_OWNER_DRAWN
 492         if ( m_windowStyle & wxLB_OWNERDRAW )
 493         {
 494             wxOwnerDrawn *pNewItem = CreateLboxItem(idx);
 495             pNewItem->SetName(items[i]);
 496             pNewItem->SetFont(GetFont());
 497             m_aItems.Insert(pNewItem, idx);
 498
 499             ListBox_SetItemData(GetHwnd(), idx, pNewItem);
 500         }
 501 #endif // wxUSE_OWNER_DRAWN
 502     }
 503
 504     m_noItems += nItems;
 505
 506     SetHorizontalExtent();
 507 }
 508
 509 void wxListBox::SetString(int N, const wxString& s)
 510 {
 511     wxCHECK_RET( N >= 0 && N < m_noItems,
 512                  wxT("invalid index in wxListBox::SetString") );
 513
 514     // remember the state of the item
 515     bool wasSelected = IsSelected(N);
 516
 517     void *oldData = NULL;
 518     wxClientData *oldObjData = NULL;
 519     if ( m_clientDataItemsType == wxClientData_Void )
 520         oldData = GetClientData(N);
 521     else if ( m_clientDataItemsType == wxClientData_Object )
 522         oldObjData = GetClientObject(N);
 523
 524     // delete and recreate it
 525     SendMessage(GetHwnd(), LB_DELETESTRING, N, 0);
 526
 527     int newN = N;
 528     if ( N == m_noItems - 1 )
 529         newN = -1;
 530
 531     ListBox_InsertString(GetHwnd(), newN, s);
 532
 533     // restore the client data
 534     if ( oldData )
 535         SetClientData(N, oldData);
 536     else if ( oldObjData )
 537         SetClientObject(N, oldObjData);
 538
 539     // we may have lost the selection
 540     if ( wasSelected )
 541         Select(N);
 542
 543 #if wxUSE_OWNER_DRAWN
 544     if ( m_windowStyle & wxLB_OWNERDRAW )
 545     {
 546         // update item's text
 547         m_aItems[N]->SetName(s);
 548
 549         // reassign the item's data
 550         ListBox_SetItemData(GetHwnd(), N, m_aItems[N]);
 551     }
 552 #endif  //USE_OWNER_DRAWN
 553 }
 554
 555 int wxListBox::GetCount() const
 556 {
 557     return m_noItems;
 558 }
 559
 560 // ----------------------------------------------------------------------------
 561 // helpers
 562 // ----------------------------------------------------------------------------
 563
 564 // Windows-specific code to set the horizontal extent of the listbox, if
 565 // necessary. If s is non-NULL, it's used to calculate the horizontal extent.
 566 // Otherwise, all strings are used.
 567 void wxListBox::SetHorizontalExtent(const wxString& s)
 568 {
 569     // Only necessary if we want a horizontal scrollbar
 570     if (!(m_windowStyle & wxHSCROLL))
 571         return;
 572     TEXTMETRIC lpTextMetric;
 573
 574     if ( !s.IsEmpty() )
 575     {
 576         int existingExtent = (int)SendMessage(GetHwnd(), LB_GETHORIZONTALEXTENT, 0, 0L);
 577         HDC dc = GetWindowDC(GetHwnd());
 578         HFONT oldFont = 0;
 579         if (GetFont().Ok() && GetFont().GetResourceHandle())
 580             oldFont = (HFONT) ::SelectObject(dc, (HFONT) GetFont().GetResourceHandle());
 581
 582         GetTextMetrics(dc, &lpTextMetric);
 583         SIZE extentXY;
 584         ::GetTextExtentPoint(dc, (LPTSTR) (const wxChar *)s, s.Length(), &extentXY);
 585         int extentX = (int)(extentXY.cx + lpTextMetric.tmAveCharWidth);
 586
 587         if (oldFont)
 588             ::SelectObject(dc, oldFont);
 589
 590         ReleaseDC(GetHwnd(), dc);
 591         if (extentX > existingExtent)
 592             SendMessage(GetHwnd(), LB_SETHORIZONTALEXTENT, LOWORD(extentX), 0L);
 593     }
 594     else
 595     {
 596         int largestExtent = 0;
 597         HDC dc = GetWindowDC(GetHwnd());
 598         HFONT oldFont = 0;
 599         if (GetFont().Ok() && GetFont().GetResourceHandle())
 600             oldFont = (HFONT) ::SelectObject(dc, (HFONT) GetFont().GetResourceHandle());
 601
 602         GetTextMetrics(dc, &lpTextMetric);
 603         int i;
 604         for (i = 0; i < m_noItems; i++)
 605         {
 606             int len = (int)SendMessage(GetHwnd(), LB_GETTEXT, i, (LONG)wxBuffer);
 607             wxBuffer[len] = 0;
 608             SIZE extentXY;
 609             ::GetTextExtentPoint(dc, (LPTSTR)wxBuffer, len, &extentXY);
 610             int extentX = (int)(extentXY.cx + lpTextMetric.tmAveCharWidth);
 611             if (extentX > largestExtent)
 612                 largestExtent = extentX;
 613         }
 614         if (oldFont)
 615             ::SelectObject(dc, oldFont);
 616
 617         ReleaseDC(GetHwnd(), dc);
 618         SendMessage(GetHwnd(), LB_SETHORIZONTALEXTENT, LOWORD(largestExtent), 0L);
 619     }
 620 }
 621
 622 wxSize wxListBox::DoGetBestSize() const
 623 {
 624     // find the widest string
 625     int wLine;
 626     int wListbox = 0;
 627     for ( int i = 0; i < m_noItems; i++ )
 628     {
 629         wxString str(GetString(i));
 630         GetTextExtent(str, &wLine, NULL);
 631         if ( wLine > wListbox )
 632             wListbox = wLine;
 633     }
 634
 635     // give it some reasonable default value if there are no strings in the
 636     // list
 637     if ( wListbox == 0 )
 638         wListbox = 100;
 639
 640     // the listbox should be slightly larger than the widest string
 641     int cx, cy;
 642     wxGetCharSize(GetHWND(), &cx, &cy, &GetFont());
 643
 644     wListbox += 3*cx;
 645
 646     // don't make the listbox too tall (limit height to 10 items) but don't
 647     // make it too small neither
 648     int hListbox = EDIT_HEIGHT_FROM_CHAR_HEIGHT(cy)*
 649                     wxMin(wxMax(m_noItems, 3), 10);
 650
 651     return wxSize(wListbox, hListbox);
 652 }
 653
 654 // ----------------------------------------------------------------------------
 655 // callbacks
 656 // ----------------------------------------------------------------------------
 657
 658 bool wxListBox::MSWCommand(WXUINT param, WXWORD WXUNUSED(id))
 659 {
 660     wxEventType evtType;
 661     if ( param == LBN_SELCHANGE )
 662     {
 663         evtType = wxEVT_COMMAND_LISTBOX_SELECTED;
 664     }
 665     else if ( param == LBN_DBLCLK )
 666     {
 667         evtType = wxEVT_COMMAND_LISTBOX_DOUBLECLICKED;
 668     }
 669     else
 670     {
 671         // some event we're not interested in
 672         return FALSE;
 673     }
 674
 675     wxCommandEvent event(evtType, m_windowId);
 676     event.SetEventObject( this );
 677
 678     wxArrayInt aSelections;
 679     int n, count = GetSelections(aSelections);
 680     if ( count > 0 )
 681     {
 682         n = aSelections[0];
 683         if ( HasClientObjectData() )
 684             event.SetClientObject( GetClientObject(n) );
 685         else if ( HasClientUntypedData() )
 686             event.SetClientData( GetClientData(n) );
 687         event.SetString( GetString(n) );
 688     }
 689     else
 690     {
 691         n = -1;
 692     }
 693
 694     event.m_commandInt = n;
 695
 696     return GetEventHandler()->ProcessEvent(event);
 697 }
 698
 699 // ----------------------------------------------------------------------------
 700 // wxCheckListBox support
 701 // ----------------------------------------------------------------------------
 702
 703 #if wxUSE_OWNER_DRAWN
 704
 705 // drawing
 706 // -------
 707
 708 // space beneath/above each row in pixels
 709 // "standard" checklistbox use 1 here, some might prefer 2. 0 is ugly.
 710 #define OWNER_DRAWN_LISTBOX_EXTRA_SPACE    (1)
 711
 712 // the height is the same for all items
 713 // TODO should be changed for LBS_OWNERDRAWVARIABLE style listboxes
 714
 715 // NB: can't forward this to wxListBoxItem because LB_SETITEMDATA
 716 //     message is not yet sent when we get here!
 717 bool wxListBox::MSWOnMeasure(WXMEASUREITEMSTRUCT *item)
 718 {
 719     // only owner-drawn control should receive this message
 720     wxCHECK( ((m_windowStyle & wxLB_OWNERDRAW) == wxLB_OWNERDRAW), FALSE );
 721
 722     MEASUREITEMSTRUCT *pStruct = (MEASUREITEMSTRUCT *)item;
 723
 724     HDC hdc = CreateIC(wxT("DISPLAY"), NULL, NULL, 0);
 725
 726     wxDC dc;
 727     dc.SetHDC((WXHDC)hdc);
 728     dc.SetFont(wxSystemSettings::GetFont(wxSYS_ANSI_VAR_FONT));
 729
 730     pStruct->itemHeight = dc.GetCharHeight() + 2*OWNER_DRAWN_LISTBOX_EXTRA_SPACE;
 731     pStruct->itemWidth  = dc.GetCharWidth();
 732
 733     dc.SetHDC(0);
 734
 735     DeleteDC(hdc);
 736
 737     return TRUE;
 738 }
 739
 740 // forward the message to the appropriate item
 741 bool wxListBox::MSWOnDraw(WXDRAWITEMSTRUCT *item)
 742 {
 743     // only owner-drawn control should receive this message
 744     wxCHECK( ((m_windowStyle & wxLB_OWNERDRAW) == wxLB_OWNERDRAW), FALSE );
 745
 746     DRAWITEMSTRUCT *pStruct = (DRAWITEMSTRUCT *)item;
 747     UINT itemID = pStruct->itemID;
 748
 749     // the item may be -1 for an empty listbox
 750     if ( itemID == (UINT)-1 )
 751         return FALSE;
 752
 753     long data = ListBox_GetItemData(GetHwnd(), pStruct->itemID);
 754
 755     wxCHECK( data && (data != LB_ERR), FALSE );
 756
 757     wxListBoxItem *pItem = (wxListBoxItem *)data;
 758
 759     wxDCTemp dc((WXHDC)pStruct->hDC);
 760     wxRect rect(wxPoint(pStruct->rcItem.left, pStruct->rcItem.top),
 761                 wxPoint(pStruct->rcItem.right, pStruct->rcItem.bottom));
 762
 763     return pItem->OnDrawItem(dc, rect,
 764                              (wxOwnerDrawn::wxODAction)pStruct->itemAction,
 765                              (wxOwnerDrawn::wxODStatus)pStruct->itemState);
 766 }
 767
 768 #endif // wxUSE_OWNER_DRAWN
 769
 770 #endif // wxUSE_LISTBOX