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 licence
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
  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 #ifdef __GNUWIN32_OLD__
  47     #include "wx/msw/gnuwin32/extra.h"
  48 #endif
  49
  50 #if wxUSE_EXTENDED_RTTI
  51 WX_DEFINE_FLAGS( wxListBoxStyle )
  52
  53 WX_BEGIN_FLAGS( wxListBoxStyle )
  54     // new style border flags, we put them first to
  55     // use them for streaming out
  56     WX_FLAGS_MEMBER(wxBORDER_SIMPLE)
  57     WX_FLAGS_MEMBER(wxBORDER_SUNKEN)
  58     WX_FLAGS_MEMBER(wxBORDER_DOUBLE)
  59     WX_FLAGS_MEMBER(wxBORDER_RAISED)
  60     WX_FLAGS_MEMBER(wxBORDER_STATIC)
  61     WX_FLAGS_MEMBER(wxBORDER_NONE)
  62
  63     // old style border flags
  64     WX_FLAGS_MEMBER(wxSIMPLE_BORDER)
  65     WX_FLAGS_MEMBER(wxSUNKEN_BORDER)
  66     WX_FLAGS_MEMBER(wxDOUBLE_BORDER)
  67     WX_FLAGS_MEMBER(wxRAISED_BORDER)
  68     WX_FLAGS_MEMBER(wxSTATIC_BORDER)
  69     WX_FLAGS_MEMBER(wxNO_BORDER)
  70
  71     // standard window styles
  72     WX_FLAGS_MEMBER(wxTAB_TRAVERSAL)
  73     WX_FLAGS_MEMBER(wxCLIP_CHILDREN)
  74     WX_FLAGS_MEMBER(wxTRANSPARENT_WINDOW)
  75     WX_FLAGS_MEMBER(wxWANTS_CHARS)
  76     WX_FLAGS_MEMBER(wxNO_FULL_REPAINT_ON_RESIZE)
  77     WX_FLAGS_MEMBER(wxALWAYS_SHOW_SB )
  78     WX_FLAGS_MEMBER(wxVSCROLL)
  79     WX_FLAGS_MEMBER(wxHSCROLL)
  80
  81     WX_FLAGS_MEMBER(wxLB_SINGLE)
  82     WX_FLAGS_MEMBER(wxLB_MULTIPLE)
  83     WX_FLAGS_MEMBER(wxLB_EXTENDED)
  84     WX_FLAGS_MEMBER(wxLB_HSCROLL)
  85     WX_FLAGS_MEMBER(wxLB_ALWAYS_SB)
  86     WX_FLAGS_MEMBER(wxLB_NEEDED_SB)
  87     WX_FLAGS_MEMBER(wxLB_SORT)
  88
  89 WX_END_FLAGS( wxListBoxStyle )
  90
  91 IMPLEMENT_DYNAMIC_CLASS_XTI(wxListBox, wxControl,"wx/listbox.h")
  92
  93 WX_BEGIN_PROPERTIES_TABLE(wxListBox)
  94     // TODO DELEGATES
  95         WX_PROPERTY( Font , wxFont , SetFont , GetFont  , , 0 /*flags*/ , wxT("Helpstring") , wxT("group"))
  96     WX_PROPERTY_COLLECTION( Choices , wxArrayString , wxString , AppendString , GetStrings, 0 /*flags*/ , wxT("Helpstring") , wxT("group") )
  97         WX_PROPERTY( Selection ,int, SetSelection, GetSelection,, 0 /*flags*/ , wxT("Helpstring") , wxT("group") )
  98     WX_PROPERTY_FLAGS( WindowStyle , wxListBoxStyle , long , SetWindowStyleFlag , GetWindowStyleFlag , , 0 /*flags*/ , wxT("Helpstring") , wxT("group")) // style
  99 WX_END_PROPERTIES_TABLE()
 100
 101 WX_BEGIN_HANDLERS_TABLE(wxListBox)
 102 WX_END_HANDLERS_TABLE()
 103
 104 WX_CONSTRUCTOR_4( wxListBox , wxWindow* , Parent , wxWindowID , Id , wxPoint , Position , wxSize , Size )
 105 #else
 106 IMPLEMENT_DYNAMIC_CLASS(wxListBox, wxControl)
 107 #endif
 108
 109 /*
 110 TODO PROPERTIES
 111         selection
 112         content
 113                 item
 114 */
 115
 116 // ============================================================================
 117 // list box item declaration and implementation
 118 // ============================================================================
 119
 120 #if wxUSE_OWNER_DRAWN
 121
 122 class wxListBoxItem : public wxOwnerDrawn
 123 {
 124 public:
 125     wxListBoxItem(const wxString& str = wxEmptyString);
 126 };
 127
 128 wxListBoxItem::wxListBoxItem(const wxString& str) : wxOwnerDrawn(str, FALSE)
 129 {
 130     // no bitmaps/checkmarks
 131     SetMarginWidth(0);
 132 }
 133
 134 wxOwnerDrawn *wxListBox::CreateLboxItem(size_t WXUNUSED(n))
 135 {
 136     return new wxListBoxItem();
 137 }
 138
 139 #endif  //USE_OWNER_DRAWN
 140
 141 // ============================================================================
 142 // list box control implementation
 143 // ============================================================================
 144
 145 // ----------------------------------------------------------------------------
 146 // creation
 147 // ----------------------------------------------------------------------------
 148
 149 // Listbox item
 150 wxListBox::wxListBox()
 151 {
 152     m_noItems = 0;
 153     m_selected = 0;
 154 }
 155
 156 bool wxListBox::Create(wxWindow *parent,
 157                        wxWindowID id,
 158                        const wxPoint& pos,
 159                        const wxSize& size,
 160                        int n, const wxString choices[],
 161                        long style,
 162                        const wxValidator& validator,
 163                        const wxString& name)
 164 {
 165     m_noItems = 0;
 166     m_hWnd = 0;
 167     m_selected = 0;
 168
 169     SetName(name);
 170 #if wxUSE_VALIDATORS
 171     SetValidator(validator);
 172 #endif // wxUSE_VALIDATORS
 173
 174     if (parent)
 175         parent->AddChild(this);
 176
 177     SetBackgroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_WINDOW));
 178     SetForegroundColour(parent->GetForegroundColour());
 179
 180     m_windowId = ( id == -1 ) ? (int)NewControlId() : id;
 181
 182     int x = pos.x;
 183     int y = pos.y;
 184     int width = size.x;
 185     int height = size.y;
 186     m_windowStyle = style;
 187
 188     DWORD wstyle = WS_VISIBLE | WS_CHILD | WS_VSCROLL | WS_TABSTOP |
 189                    LBS_NOTIFY | LBS_HASSTRINGS ;
 190
 191     wxASSERT_MSG( !(style & wxLB_MULTIPLE) || !(style & wxLB_EXTENDED),
 192                   _T("only one of listbox selection modes can be specified") );
 193
 194     if ( (m_windowStyle & wxBORDER_MASK) == wxBORDER_DEFAULT )
 195         m_windowStyle |= wxBORDER_SUNKEN;
 196
 197     if ( m_windowStyle & wxCLIP_SIBLINGS )
 198         wstyle |= WS_CLIPSIBLINGS;
 199
 200     if (m_windowStyle & wxLB_MULTIPLE)
 201         wstyle |= LBS_MULTIPLESEL;
 202     else if (m_windowStyle & wxLB_EXTENDED)
 203         wstyle |= LBS_EXTENDEDSEL;
 204
 205     if (m_windowStyle & wxLB_ALWAYS_SB)
 206         wstyle |= LBS_DISABLENOSCROLL;
 207     if (m_windowStyle & wxLB_HSCROLL)
 208         wstyle |= WS_HSCROLL;
 209     if (m_windowStyle & wxLB_SORT)
 210         wstyle |= LBS_SORT;
 211
 212 #if wxUSE_OWNER_DRAWN && !defined(__WXWINCE__)
 213     if ( m_windowStyle & wxLB_OWNERDRAW ) {
 214         // we don't support LBS_OWNERDRAWVARIABLE yet
 215         wstyle |= LBS_OWNERDRAWFIXED;
 216     }
 217 #endif
 218
 219     // Without this style, you get unexpected heights, so e.g. constraint layout
 220     // doesn't work properly
 221     wstyle |= LBS_NOINTEGRALHEIGHT;
 222
 223     WXDWORD exStyle = 0;
 224     (void) MSWGetStyle(m_windowStyle, & exStyle) ;
 225
 226     m_hWnd = (WXHWND)::CreateWindowEx(exStyle, wxT("LISTBOX"), NULL,
 227             wstyle ,
 228             0, 0, 0, 0,
 229             (HWND)parent->GetHWND(), (HMENU)m_windowId,
 230             wxGetInstance(), NULL);
 231
 232     wxCHECK_MSG( m_hWnd, FALSE, wxT("Failed to create listbox") );
 233
 234     // Subclass again to catch messages
 235     SubclassWin(m_hWnd);
 236
 237     size_t ui;
 238     for (ui = 0; ui < (size_t)n; ui++) {
 239         Append(choices[ui]);
 240     }
 241
 242     if ( (m_windowStyle & wxLB_MULTIPLE) == 0 )
 243         SendMessage(GetHwnd(), LB_SETCURSEL, 0, 0);
 244
 245     SetFont(parent->GetFont());
 246
 247     SetSize(x, y, width, height);
 248
 249     return TRUE;
 250 }
 251
 252 wxListBox::~wxListBox()
 253 {
 254     Free();
 255 }
 256
 257 void wxListBox::SetupColours()
 258 {
 259     SetBackgroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_WINDOW));
 260     SetForegroundColour(GetParent()->GetForegroundColour());
 261 }
 262
 263 // ----------------------------------------------------------------------------
 264 // implementation of wxListBoxBase methods
 265 // ----------------------------------------------------------------------------
 266
 267 void wxListBox::DoSetFirstItem(int N)
 268 {
 269     wxCHECK_RET( N >= 0 && N < m_noItems,
 270                  wxT("invalid index in wxListBox::SetFirstItem") );
 271
 272     SendMessage(GetHwnd(), LB_SETTOPINDEX, (WPARAM)N, (LPARAM)0);
 273 }
 274
 275 void wxListBox::Delete(int N)
 276 {
 277     wxCHECK_RET( N >= 0 && N < m_noItems,
 278                  wxT("invalid index in wxListBox::Delete") );
 279
 280     // for owner drawn objects, the data is used for storing wxOwnerDrawn
 281     // pointers and we shouldn't touch it
 282 #if !wxUSE_OWNER_DRAWN
 283     if ( !(m_windowStyle & wxLB_OWNERDRAW) )
 284 #endif // !wxUSE_OWNER_DRAWN
 285         if ( HasClientObjectData() )
 286         {
 287             delete GetClientObject(N);
 288         }
 289
 290     SendMessage(GetHwnd(), LB_DELETESTRING, N, 0);
 291     m_noItems--;
 292
 293     SetHorizontalExtent(wxEmptyString);
 294 }
 295
 296 int wxListBox::DoAppend(const wxString& item)
 297 {
 298     int index = ListBox_AddString(GetHwnd(), item);
 299     m_noItems++;
 300
 301 #if wxUSE_OWNER_DRAWN
 302     if ( m_windowStyle & wxLB_OWNERDRAW ) {
 303         wxOwnerDrawn *pNewItem = CreateLboxItem(index); // dummy argument
 304         pNewItem->SetName(item);
 305         m_aItems.Insert(pNewItem, index);
 306         ListBox_SetItemData(GetHwnd(), index, pNewItem);
 307         pNewItem->SetFont(GetFont());
 308     }
 309 #endif // wxUSE_OWNER_DRAWN
 310
 311     SetHorizontalExtent(item);
 312
 313     return index;
 314 }
 315
 316 void wxListBox::DoSetItems(const wxArrayString& choices, void** clientData)
 317 {
 318     // avoid flicker - but don't need to do this for a hidden listbox
 319     bool hideAndShow = IsShown();
 320     if ( hideAndShow )
 321     {
 322         ShowWindow(GetHwnd(), SW_HIDE);
 323     }
 324
 325     ListBox_ResetContent(GetHwnd());
 326
 327     m_noItems = choices.GetCount();
 328     int i;
 329     for (i = 0; i < m_noItems; i++)
 330     {
 331         ListBox_AddString(GetHwnd(), choices[i]);
 332         if ( clientData )
 333         {
 334             SetClientData(i, clientData[i]);
 335         }
 336     }
 337
 338 #if wxUSE_OWNER_DRAWN
 339     if ( m_windowStyle & wxLB_OWNERDRAW ) {
 340         // first delete old items
 341         WX_CLEAR_ARRAY(m_aItems);
 342
 343         // then create new ones
 344         for ( size_t ui = 0; ui < (size_t)m_noItems; ui++ ) {
 345             wxOwnerDrawn *pNewItem = CreateLboxItem(ui);
 346             pNewItem->SetName(choices[ui]);
 347             m_aItems.Add(pNewItem);
 348             ListBox_SetItemData(GetHwnd(), ui, pNewItem);
 349         }
 350     }
 351 #endif // wxUSE_OWNER_DRAWN
 352
 353     SetHorizontalExtent();
 354
 355     if ( hideAndShow )
 356     {
 357         // show the listbox back if we hid it
 358         ShowWindow(GetHwnd(), SW_SHOW);
 359     }
 360 }
 361
 362 int wxListBox::FindString(const wxString& s) const
 363 {
 364     int pos = ListBox_FindStringExact(GetHwnd(), (WPARAM)-1, s);
 365     if (pos == LB_ERR)
 366         return wxNOT_FOUND;
 367     else
 368         return pos;
 369 }
 370
 371 void wxListBox::Clear()
 372 {
 373     Free();
 374
 375     ListBox_ResetContent(GetHwnd());
 376
 377     m_noItems = 0;
 378     SetHorizontalExtent();
 379 }
 380
 381 void wxListBox::Free()
 382 {
 383 #if wxUSE_OWNER_DRAWN
 384     if ( m_windowStyle & wxLB_OWNERDRAW )
 385     {
 386         WX_CLEAR_ARRAY(m_aItems);
 387     }
 388     else
 389 #endif // wxUSE_OWNER_DRAWN
 390     if ( HasClientObjectData() )
 391     {
 392         for ( size_t n = 0; n < (size_t)m_noItems; n++ )
 393         {
 394             delete GetClientObject(n);
 395         }
 396     }
 397 }
 398
 399 void wxListBox::SetSelection(int N, bool select)
 400 {
 401     wxCHECK_RET( N >= 0 && N < m_noItems,
 402                  wxT("invalid index in wxListBox::SetSelection") );
 403
 404     if ( HasMultipleSelection() )
 405     {
 406         SendMessage(GetHwnd(), LB_SETSEL, select, N);
 407     }
 408     else
 409     {
 410         SendMessage(GetHwnd(), LB_SETCURSEL, select ? N : -1, 0);
 411     }
 412 }
 413
 414 bool wxListBox::IsSelected(int N) const
 415 {
 416     wxCHECK_MSG( N >= 0 && N < m_noItems, FALSE,
 417                  wxT("invalid index in wxListBox::Selected") );
 418
 419     return SendMessage(GetHwnd(), LB_GETSEL, N, 0) == 0 ? FALSE : TRUE;
 420 }
 421
 422 wxClientData* wxListBox::DoGetItemClientObject(int n) const
 423 {
 424     return (wxClientData *)DoGetItemClientData(n);
 425 }
 426
 427 void *wxListBox::DoGetItemClientData(int n) const
 428 {
 429     wxCHECK_MSG( n >= 0 && n < m_noItems, NULL,
 430                  wxT("invalid index in wxListBox::GetClientData") );
 431
 432     return (void *)SendMessage(GetHwnd(), LB_GETITEMDATA, n, 0);
 433 }
 434
 435 void wxListBox::DoSetItemClientObject(int n, wxClientData* clientData)
 436 {
 437     DoSetItemClientData(n, clientData);
 438 }
 439
 440 void wxListBox::DoSetItemClientData(int n, void *clientData)
 441 {
 442     wxCHECK_RET( n >= 0 && n < m_noItems,
 443                  wxT("invalid index in wxListBox::SetClientData") );
 444
 445 #if wxUSE_OWNER_DRAWN
 446     if ( m_windowStyle & wxLB_OWNERDRAW )
 447     {
 448         // client data must be pointer to wxOwnerDrawn, otherwise we would crash
 449         // in OnMeasure/OnDraw.
 450         wxFAIL_MSG(wxT("Can't use client data with owner-drawn listboxes"));
 451     }
 452 #endif // wxUSE_OWNER_DRAWN
 453
 454     if ( ListBox_SetItemData(GetHwnd(), n, clientData) == LB_ERR )
 455         wxLogDebug(wxT("LB_SETITEMDATA failed"));
 456 }
 457
 458 // Return number of selections and an array of selected integers
 459 int wxListBox::GetSelections(wxArrayInt& aSelections) const
 460 {
 461     aSelections.Empty();
 462
 463     if ( HasMultipleSelection() )
 464     {
 465         int countSel = ListBox_GetSelCount(GetHwnd());
 466         if ( countSel == LB_ERR )
 467         {
 468             wxLogDebug(_T("ListBox_GetSelCount failed"));
 469         }
 470         else if ( countSel != 0 )
 471         {
 472             int *selections = new int[countSel];
 473
 474             if ( ListBox_GetSelItems(GetHwnd(),
 475                                      countSel, selections) == LB_ERR )
 476             {
 477                 wxLogDebug(wxT("ListBox_GetSelItems failed"));
 478                 countSel = -1;
 479             }
 480             else
 481             {
 482                 aSelections.Alloc(countSel);
 483                 for ( int n = 0; n < countSel; n++ )
 484                     aSelections.Add(selections[n]);
 485             }
 486
 487             delete [] selections;
 488         }
 489
 490         return countSel;
 491     }
 492     else  // single-selection listbox
 493     {
 494         if (ListBox_GetCurSel(GetHwnd()) > -1)
 495             aSelections.Add(ListBox_GetCurSel(GetHwnd()));
 496
 497         return aSelections.Count();
 498     }
 499 }
 500
 501 // Get single selection, for single choice list items
 502 int wxListBox::GetSelection() const
 503 {
 504     wxCHECK_MSG( !HasMultipleSelection(),
 505                  -1,
 506                  wxT("GetSelection() can't be used with multiple-selection listboxes, use GetSelections() instead.") );
 507
 508     return ListBox_GetCurSel(GetHwnd());
 509 }
 510
 511 // Find string for position
 512 wxString wxListBox::GetString(int N) const
 513 {
 514     wxCHECK_MSG( N >= 0 && N < m_noItems, wxEmptyString,
 515                  wxT("invalid index in wxListBox::GetClientData") );
 516
 517     int len = ListBox_GetTextLen(GetHwnd(), N);
 518
 519     // +1 for terminating NUL
 520     wxString result;
 521     ListBox_GetText(GetHwnd(), N, wxStringBuffer(result, len + 1));
 522
 523     return result;
 524 }
 525
 526 void
 527 wxListBox::DoInsertItems(const wxArrayString& items, int pos)
 528 {
 529     wxCHECK_RET( pos >= 0 && pos <= m_noItems,
 530                  wxT("invalid index in wxListBox::InsertItems") );
 531
 532     int nItems = items.GetCount();
 533     for ( int i = 0; i < nItems; i++ )
 534     {
 535         int idx = ListBox_InsertString(GetHwnd(), i + pos, items[i]);
 536
 537 #if wxUSE_OWNER_DRAWN
 538         if ( m_windowStyle & wxLB_OWNERDRAW )
 539         {
 540             wxOwnerDrawn *pNewItem = CreateLboxItem(idx);
 541             pNewItem->SetName(items[i]);
 542             pNewItem->SetFont(GetFont());
 543             m_aItems.Insert(pNewItem, idx);
 544
 545             ListBox_SetItemData(GetHwnd(), idx, pNewItem);
 546         }
 547 #endif // wxUSE_OWNER_DRAWN
 548     }
 549
 550     m_noItems += nItems;
 551
 552     SetHorizontalExtent();
 553 }
 554
 555 void wxListBox::SetString(int N, const wxString& s)
 556 {
 557     wxCHECK_RET( N >= 0 && N < m_noItems,
 558                  wxT("invalid index in wxListBox::SetString") );
 559
 560     // remember the state of the item
 561     bool wasSelected = IsSelected(N);
 562
 563     void *oldData = NULL;
 564     wxClientData *oldObjData = NULL;
 565     if ( m_clientDataItemsType == wxClientData_Void )
 566         oldData = GetClientData(N);
 567     else if ( m_clientDataItemsType == wxClientData_Object )
 568         oldObjData = GetClientObject(N);
 569
 570     // delete and recreate it
 571     SendMessage(GetHwnd(), LB_DELETESTRING, N, 0);
 572
 573     int newN = N;
 574     if ( N == m_noItems - 1 )
 575         newN = -1;
 576
 577     ListBox_InsertString(GetHwnd(), newN, s);
 578
 579     // restore the client data
 580     if ( oldData )
 581         SetClientData(N, oldData);
 582     else if ( oldObjData )
 583         SetClientObject(N, oldObjData);
 584
 585     // we may have lost the selection
 586     if ( wasSelected )
 587         Select(N);
 588
 589 #if wxUSE_OWNER_DRAWN
 590     if ( m_windowStyle & wxLB_OWNERDRAW )
 591     {
 592         // update item's text
 593         m_aItems[N]->SetName(s);
 594
 595         // reassign the item's data
 596         ListBox_SetItemData(GetHwnd(), N, m_aItems[N]);
 597     }
 598 #endif  //USE_OWNER_DRAWN
 599 }
 600
 601 int wxListBox::GetCount() const
 602 {
 603     return m_noItems;
 604 }
 605
 606 // ----------------------------------------------------------------------------
 607 // helpers
 608 // ----------------------------------------------------------------------------
 609
 610 // Windows-specific code to set the horizontal extent of the listbox, if
 611 // necessary. If s is non-NULL, it's used to calculate the horizontal extent.
 612 // Otherwise, all strings are used.
 613 void wxListBox::SetHorizontalExtent(const wxString& s)
 614 {
 615     // Only necessary if we want a horizontal scrollbar
 616     if (!(m_windowStyle & wxHSCROLL))
 617         return;
 618     TEXTMETRIC lpTextMetric;
 619
 620     if ( !s.IsEmpty() )
 621     {
 622         int existingExtent = (int)SendMessage(GetHwnd(), LB_GETHORIZONTALEXTENT, 0, 0L);
 623         HDC dc = GetWindowDC(GetHwnd());
 624         HFONT oldFont = 0;
 625         if (GetFont().Ok() && GetFont().GetResourceHandle())
 626             oldFont = (HFONT) ::SelectObject(dc, (HFONT) GetFont().GetResourceHandle());
 627
 628         GetTextMetrics(dc, &lpTextMetric);
 629         SIZE extentXY;
 630         ::GetTextExtentPoint(dc, (LPTSTR) (const wxChar *)s, s.Length(), &extentXY);
 631         int extentX = (int)(extentXY.cx + lpTextMetric.tmAveCharWidth);
 632
 633         if (oldFont)
 634             ::SelectObject(dc, oldFont);
 635
 636         ReleaseDC(GetHwnd(), dc);
 637         if (extentX > existingExtent)
 638             SendMessage(GetHwnd(), LB_SETHORIZONTALEXTENT, LOWORD(extentX), 0L);
 639     }
 640     else
 641     {
 642         int largestExtent = 0;
 643         HDC dc = GetWindowDC(GetHwnd());
 644         HFONT oldFont = 0;
 645         if (GetFont().Ok() && GetFont().GetResourceHandle())
 646             oldFont = (HFONT) ::SelectObject(dc, (HFONT) GetFont().GetResourceHandle());
 647
 648         GetTextMetrics(dc, &lpTextMetric);
 649
 650         // FIXME: buffer overflow!!
 651         wxChar buf[1024];
 652         for (int i = 0; i < m_noItems; i++)
 653         {
 654             int len = (int)SendMessage(GetHwnd(), LB_GETTEXT, i, (LPARAM)buf);
 655             buf[len] = 0;
 656             SIZE extentXY;
 657             ::GetTextExtentPoint(dc, buf, len, &extentXY);
 658             int extentX = (int)(extentXY.cx + lpTextMetric.tmAveCharWidth);
 659             if (extentX > largestExtent)
 660                 largestExtent = extentX;
 661         }
 662         if (oldFont)
 663             ::SelectObject(dc, oldFont);
 664
 665         ReleaseDC(GetHwnd(), dc);
 666         SendMessage(GetHwnd(), LB_SETHORIZONTALEXTENT, LOWORD(largestExtent), 0L);
 667     }
 668 }
 669
 670 wxSize wxListBox::DoGetBestSize() const
 671 {
 672     // find the widest string
 673     int wLine;
 674     int wListbox = 0;
 675     for ( int i = 0; i < m_noItems; i++ )
 676     {
 677         wxString str(GetString(i));
 678         GetTextExtent(str, &wLine, NULL);
 679         if ( wLine > wListbox )
 680             wListbox = wLine;
 681     }
 682
 683     // give it some reasonable default value if there are no strings in the
 684     // list
 685     if ( wListbox == 0 )
 686         wListbox = 100;
 687
 688     // the listbox should be slightly larger than the widest string
 689     int cx, cy;
 690     wxGetCharSize(GetHWND(), &cx, &cy, &GetFont());
 691
 692     wListbox += 3*cx;
 693
 694     // don't make the listbox too tall (limit height to 10 items) but don't
 695     // make it too small neither
 696     int hListbox = EDIT_HEIGHT_FROM_CHAR_HEIGHT(cy)*
 697                     wxMin(wxMax(m_noItems, 3), 10);
 698
 699     return wxSize(wListbox, hListbox);
 700 }
 701
 702 // ----------------------------------------------------------------------------
 703 // callbacks
 704 // ----------------------------------------------------------------------------
 705
 706 bool wxListBox::MSWCommand(WXUINT param, WXWORD WXUNUSED(id))
 707 {
 708     wxEventType evtType;
 709     if ( param == LBN_SELCHANGE )
 710     {
 711         evtType = wxEVT_COMMAND_LISTBOX_SELECTED;
 712     }
 713     else if ( param == LBN_DBLCLK )
 714     {
 715         evtType = wxEVT_COMMAND_LISTBOX_DOUBLECLICKED;
 716     }
 717     else
 718     {
 719         // some event we're not interested in
 720         return FALSE;
 721     }
 722
 723     wxCommandEvent event(evtType, m_windowId);
 724     event.SetEventObject( this );
 725
 726     // retrieve the affected item
 727     int n = SendMessage(GetHwnd(), LB_GETCARETINDEX, 0, 0);
 728     if ( n != LB_ERR )
 729     {
 730         if ( HasClientObjectData() )
 731             event.SetClientObject( GetClientObject(n) );
 732         else if ( HasClientUntypedData() )
 733             event.SetClientData( GetClientData(n) );
 734
 735         event.SetString( GetString(n) );
 736         event.SetExtraLong( HasMultipleSelection() ? IsSelected(n) : TRUE );
 737     }
 738
 739     event.m_commandInt = n;
 740
 741     return GetEventHandler()->ProcessEvent(event);
 742 }
 743
 744 // ----------------------------------------------------------------------------
 745 // wxCheckListBox support
 746 // ----------------------------------------------------------------------------
 747
 748 #if wxUSE_OWNER_DRAWN
 749
 750 // drawing
 751 // -------
 752
 753 // space beneath/above each row in pixels
 754 // "standard" checklistbox use 1 here, some might prefer 2. 0 is ugly.
 755 #define OWNER_DRAWN_LISTBOX_EXTRA_SPACE    (1)
 756
 757 // the height is the same for all items
 758 // TODO should be changed for LBS_OWNERDRAWVARIABLE style listboxes
 759
 760 // NB: can't forward this to wxListBoxItem because LB_SETITEMDATA
 761 //     message is not yet sent when we get here!
 762 bool wxListBox::MSWOnMeasure(WXMEASUREITEMSTRUCT *item)
 763 {
 764     // only owner-drawn control should receive this message
 765     wxCHECK( ((m_windowStyle & wxLB_OWNERDRAW) == wxLB_OWNERDRAW), FALSE );
 766
 767     MEASUREITEMSTRUCT *pStruct = (MEASUREITEMSTRUCT *)item;
 768
 769 #ifdef __WXWINCE__
 770     HDC hdc = GetDC(NULL);
 771 #else
 772     HDC hdc = CreateIC(wxT("DISPLAY"), NULL, NULL, 0);
 773 #endif
 774
 775     wxDC dc;
 776     dc.SetHDC((WXHDC)hdc);
 777     dc.SetFont(wxSystemSettings::GetFont(wxSYS_ANSI_VAR_FONT));
 778
 779     pStruct->itemHeight = dc.GetCharHeight() + 2*OWNER_DRAWN_LISTBOX_EXTRA_SPACE;
 780     pStruct->itemWidth  = dc.GetCharWidth();
 781
 782     dc.SetHDC(0);
 783
 784     DeleteDC(hdc);
 785
 786     return TRUE;
 787 }
 788
 789 // forward the message to the appropriate item
 790 bool wxListBox::MSWOnDraw(WXDRAWITEMSTRUCT *item)
 791 {
 792     // only owner-drawn control should receive this message
 793     wxCHECK( ((m_windowStyle & wxLB_OWNERDRAW) == wxLB_OWNERDRAW), FALSE );
 794
 795     DRAWITEMSTRUCT *pStruct = (DRAWITEMSTRUCT *)item;
 796     UINT itemID = pStruct->itemID;
 797
 798     // the item may be -1 for an empty listbox
 799     if ( itemID == (UINT)-1 )
 800         return FALSE;
 801
 802     long data = ListBox_GetItemData(GetHwnd(), pStruct->itemID);
 803
 804     wxCHECK( data && (data != LB_ERR), FALSE );
 805
 806     wxListBoxItem *pItem = (wxListBoxItem *)data;
 807
 808     wxDCTemp dc((WXHDC)pStruct->hDC);
 809     wxRect rect(wxPoint(pStruct->rcItem.left, pStruct->rcItem.top),
 810                 wxPoint(pStruct->rcItem.right, pStruct->rcItem.bottom));
 811
 812     return pItem->OnDrawItem(dc, rect,
 813                              (wxOwnerDrawn::wxODAction)pStruct->itemAction,
 814                              (wxOwnerDrawn::wxODStatus)pStruct->itemState);
 815 }
 816
 817 #endif // wxUSE_OWNER_DRAWN
 818
 819 #endif // wxUSE_LISTBOX