src/msw/msgdlg.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/msw/msgdlg.cpp
   3 // Purpose:     wxMessageDialog
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     04/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Julian Smart
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // For compilers that support precompilation, includes "wx.h".
  13 #include "wx/wxprec.h"
  14
  15 #ifdef __BORLANDC__
  16     #pragma hdrstop
  17 #endif
  18
  19 #if wxUSE_MSGDLG
  20
  21 #include "wx/msgdlg.h"
  22
  23 // there is no hook support under CE so we can't use the code for message box
  24 // positioning there
  25 #ifndef __WXWINCE__
  26     #define wxUSE_MSGBOX_HOOK 1
  27 #else
  28     #define wxUSE_MSGBOX_HOOK 0
  29 #endif
  30
  31 #ifndef WX_PRECOMP
  32     #include "wx/app.h"
  33     #include "wx/intl.h"
  34     #include "wx/utils.h"
  35     #include "wx/dialog.h"
  36     #if wxUSE_MSGBOX_HOOK
  37         #include "wx/hashmap.h"
  38     #endif
  39 #endif
  40
  41 #include "wx/msw/private.h"
  42 #include "wx/msw/private/button.h"
  43 #include "wx/msw/private/metrics.h"
  44
  45 #if wxUSE_MSGBOX_HOOK
  46     #include "wx/fontutil.h"
  47     #include "wx/textbuf.h"
  48     #include "wx/display.h"
  49 #endif
  50
  51 // For MB_TASKMODAL
  52 #ifdef __WXWINCE__
  53     #include "wx/msw/wince/missing.h"
  54 #endif
  55
  56 IMPLEMENT_CLASS(wxMessageDialog, wxDialog)
  57
  58 #if wxUSE_MSGBOX_HOOK
  59
  60 // there can potentially be one message box per thread so we use a hash map
  61 // with thread ids as keys and (currently shown) message boxes as values
  62 //
  63 // TODO: replace this with wxTLS once it's available
  64 WX_DECLARE_HASH_MAP(unsigned long, wxMessageDialog *,
  65                     wxIntegerHash, wxIntegerEqual,
  66                     wxMessageDialogMap);
  67
  68 // the order in this array is the one in which buttons appear in the
  69 // message box
  70 const wxMessageDialog::ButtonAccessors wxMessageDialog::ms_buttons[] =
  71 {
  72     { IDYES,    &wxMessageDialog::GetYesLabel    },
  73     { IDNO,     &wxMessageDialog::GetNoLabel     },
  74     { IDOK,     &wxMessageDialog::GetOKLabel     },
  75     { IDCANCEL, &wxMessageDialog::GetCancelLabel },
  76 };
  77
  78 namespace
  79 {
  80
  81 wxMessageDialogMap& HookMap()
  82 {
  83     static wxMessageDialogMap s_Map;
  84
  85     return s_Map;
  86 }
  87
  88 /*
  89     All this code is used for adjusting the message box layout when we mess
  90     with its contents. It's rather complicated because we try hard to avoid
  91     assuming much about the standard layout details and so, instead of just
  92     laying out everything ourselves (which would have been so much simpler!)
  93     we try to only modify the existing controls positions by offsetting them
  94     from their default ones in the hope that this will continue to work with
  95     the future Windows versions.
  96  */
  97
  98 // convert the given RECT from screen to client coordinates in place
  99 void ScreenRectToClient(HWND hwnd, RECT& rc)
 100 {
 101     // map from desktop (i.e. screen) coordinates to ones of this window
 102     //
 103     // notice that a RECT is laid out as 2 consecutive POINTs so the cast is
 104     // valid
 105     ::MapWindowPoints(HWND_DESKTOP, hwnd, reinterpret_cast<POINT *>(&rc), 2);
 106 }
 107
 108 // set window position to the given rect
 109 inline void SetWindowRect(HWND hwnd, const RECT& rc)
 110 {
 111     ::MoveWindow(hwnd,
 112                  rc.left, rc.top,
 113                  rc.right - rc.left, rc.bottom - rc.top,
 114                  FALSE);
 115 }
 116
 117 // set window position expressed in screen coordinates, whether the window is
 118 // child or top level
 119 void MoveWindowToScreenRect(HWND hwnd, RECT rc)
 120 {
 121     ScreenRectToClient(::GetParent(hwnd), rc);
 122
 123     SetWindowRect(hwnd, rc);
 124 }
 125
 126 // helper of AdjustButtonLabels(): move the given window by dx
 127 //
 128 // works for both child and top level windows
 129 void OffsetWindow(HWND hwnd, int dx)
 130 {
 131     RECT rc = wxGetWindowRect(hwnd);
 132
 133     rc.left += dx;
 134     rc.right += dx;
 135
 136     MoveWindowToScreenRect(hwnd, rc);
 137 }
 138
 139 } // anonymous namespace
 140
 141 /* static */
 142 WXLRESULT wxCALLBACK
 143 wxMessageDialog::HookFunction(int code, WXWPARAM wParam, WXLPARAM lParam)
 144 {
 145     // Find the thread-local instance of wxMessageDialog
 146     const DWORD tid = ::GetCurrentThreadId();
 147     wxMessageDialogMap::iterator node = HookMap().find(tid);
 148     wxCHECK_MSG( node != HookMap().end(), false,
 149                     wxT("bogus thread id in wxMessageDialog::Hook") );
 150
 151     wxMessageDialog *  const wnd = node->second;
 152
 153     const HHOOK hhook = (HHOOK)wnd->m_hook;
 154     const LRESULT rc = ::CallNextHookEx(hhook, code, wParam, lParam);
 155
 156     if ( code == HCBT_ACTIVATE )
 157     {
 158         // we won't need this hook any longer
 159         ::UnhookWindowsHookEx(hhook);
 160         wnd->m_hook = NULL;
 161         HookMap().erase(tid);
 162
 163         wnd->SetHWND((HWND)wParam);
 164
 165         // replace the static text with an edit control if the message box is
 166         // too big to fit the display
 167         wnd->ReplaceStaticWithEdit();
 168
 169         // update the labels if necessary: we need to do it before centering
 170         // the dialog as this can change its size
 171         if ( wnd->HasCustomLabels() )
 172             wnd->AdjustButtonLabels();
 173
 174         // centre the message box on its parent if requested
 175         if ( wnd->GetMessageDialogStyle() & wxCENTER )
 176             wnd->Center(); // center on parent
 177         //else: default behaviour, center on screen
 178
 179         // there seems to be no reason to leave it set
 180         wnd->SetHWND(NULL);
 181     }
 182
 183     return rc;
 184 }
 185
 186 void wxMessageDialog::ReplaceStaticWithEdit()
 187 {
 188     // check if the message box fits the display
 189     int nDisplay = wxDisplay::GetFromWindow(this);
 190     if ( nDisplay == wxNOT_FOUND )
 191         nDisplay = 0;
 192     const wxRect rectDisplay = wxDisplay(nDisplay).GetClientArea();
 193
 194     if ( rectDisplay.Contains(GetRect()) )
 195     {
 196         // nothing to do
 197         return;
 198     }
 199
 200
 201     // find the static control to replace: normally there are two of them, the
 202     // icon and the text itself so search for all of them and ignore the icon
 203     // ones
 204     HWND hwndStatic = ::FindWindowEx(GetHwnd(), NULL, _T("STATIC"), NULL);
 205     if ( ::GetWindowLong(hwndStatic, GWL_STYLE) & SS_ICON )
 206         hwndStatic = ::FindWindowEx(GetHwnd(), hwndStatic, _T("STATIC"), NULL);
 207
 208     if ( !hwndStatic )
 209     {
 210         wxLogDebug("Failed to find the static text control in message box.");
 211         return;
 212     }
 213
 214     // set the right font for GetCharHeight() call below
 215     wxWindowBase::SetFont(GetMessageFont());
 216
 217     // put the new edit control at the same place
 218     RECT rc = wxGetWindowRect(hwndStatic);
 219     ScreenRectToClient(GetHwnd(), rc);
 220
 221     // but make it less tall so that the message box fits on the screen: we try
 222     // to make the message box take no more than 7/8 of the screen to leave
 223     // some space above and below it
 224     const int hText = (7*rectDisplay.height)/8 -
 225                       (
 226                          2*::GetSystemMetrics(SM_CYFIXEDFRAME) +
 227                          ::GetSystemMetrics(SM_CYCAPTION) +
 228                          5*GetCharHeight() // buttons + margins
 229                       );
 230     const int dh = (rc.bottom - rc.top) - hText; // vertical space we save
 231     rc.bottom -= dh;
 232
 233     // and it also must be wider as it needs a vertical scrollbar (in order
 234     // to preserve the word wrap, otherwise the number of lines would change
 235     // and we want the control to look as similar as possible to the original)
 236     //
 237     // NB: you would have thought that 2*SM_CXEDGE would be enough but it
 238     //     isn't, somehow, and the text control breaks lines differently from
 239     //     the static one so fudge by adding some extra space
 240     const int dw = ::GetSystemMetrics(SM_CXVSCROLL) +
 241                         4*::GetSystemMetrics(SM_CXEDGE);
 242     rc.right += dw;
 243
 244
 245     // chop of the trailing new line(s) from the message box text, they are
 246     // ignored by the static control but result in extra lines and hence extra
 247     // scrollbar position in the edit one
 248     wxString text(wxGetWindowText(hwndStatic));
 249     for ( wxString::iterator i = text.end() - 1; i != text.begin(); --i )
 250     {
 251         if ( *i != '\n' )
 252         {
 253             text.erase(i + 1, text.end());
 254             break;
 255         }
 256     }
 257
 258     // do create the new control
 259     HWND hwndEdit = ::CreateWindow
 260                       (
 261                         _T("EDIT"),
 262                         wxTextBuffer::Translate(text).wx_str(),
 263                         WS_CHILD | WS_VSCROLL | WS_VISIBLE |
 264                         ES_MULTILINE | ES_READONLY | ES_AUTOVSCROLL,
 265                         rc.left, rc.top,
 266                         rc.right - rc.left, rc.bottom - rc.top,
 267                         GetHwnd(),
 268                         NULL,
 269                         wxhInstance,
 270                         NULL
 271                       );
 272
 273     if ( !hwndEdit )
 274     {
 275         wxLogDebug("Creation of replacement edit control failed in message box");
 276         return;
 277     }
 278
 279     // copy the font from the original control
 280     LRESULT hfont = ::SendMessage(hwndStatic, WM_GETFONT, 0, 0);
 281     ::SendMessage(hwndEdit, WM_SETFONT, hfont, 0);
 282
 283     // and get rid of it
 284     ::DestroyWindow(hwndStatic);
 285
 286
 287     // shrink and centre the message box vertically and widen it box to account
 288     // for the extra scrollbar
 289     RECT rcBox = wxGetWindowRect(GetHwnd());
 290     const int hMsgBox = rcBox.bottom - rcBox.top - dh;
 291     rcBox.top = (rectDisplay.height - hMsgBox)/2;
 292     rcBox.bottom = rcBox.top + hMsgBox + (rectDisplay.height - hMsgBox)%2;
 293     rcBox.left -= dw/2;
 294     rcBox.right += dw - dw/2;
 295     SetWindowRect(GetHwnd(), rcBox);
 296
 297     // and adjust all the buttons positions
 298     for ( unsigned n = 0; n < WXSIZEOF(ms_buttons); n++ )
 299     {
 300         const HWND hwndBtn = ::GetDlgItem(GetHwnd(), ms_buttons[n].id);
 301         if ( !hwndBtn )
 302             continue;   // it's ok, not all buttons are always present
 303
 304         RECT rc = wxGetWindowRect(hwndBtn);
 305         rc.top -= dh;
 306         rc.bottom -= dh;
 307         rc.left += dw/2;
 308         rc.right += dw/2;
 309         MoveWindowToScreenRect(hwndBtn, rc);
 310     }
 311 }
 312
 313 void wxMessageDialog::AdjustButtonLabels()
 314 {
 315     // changing the button labels is the easy part but we also need to ensure
 316     // that the buttons are big enough for the label strings and increase their
 317     // size (and maybe the size of the message box itself) if they are not
 318
 319     // TODO-RTL: check whether this works correctly in RTL
 320
 321     // we want to use this font in GetTextExtent() calls below but we don't
 322     // want to send WM_SETFONT to the message box, who knows how is it going to
 323     // react to it (right now it doesn't seem to do anything but what if this
 324     // changes)
 325     wxWindowBase::SetFont(GetMessageFont());
 326
 327     // first iteration: find the widest button and update the buttons labels
 328     int wBtnOld = 0,            // current buttons width
 329         wBtnNew = 0;            // required new buttons width
 330     RECT rcBtn;                 // stores the button height and y positions
 331     unsigned numButtons = 0;    // total number of buttons in the message box
 332     unsigned n;
 333     for ( n = 0; n < WXSIZEOF(ms_buttons); n++ )
 334     {
 335         const HWND hwndBtn = ::GetDlgItem(GetHwnd(), ms_buttons[n].id);
 336         if ( !hwndBtn )
 337             continue;   // it's ok, not all buttons are always present
 338
 339         numButtons++;
 340
 341         const wxString label = (this->*ms_buttons[n].getter)();
 342         const wxSize sizeLabel = wxWindowBase::GetTextExtent(label);
 343
 344         // check if the button is big enough for this label
 345         const RECT rc = wxGetWindowRect(hwndBtn);
 346         if ( !wBtnOld )
 347         {
 348             // initialize wBtnOld using the first button width, all the other
 349             // ones should have the same one
 350             wBtnOld = rc.right - rc.left;
 351
 352             rcBtn = rc; // remember for use below when we reposition the buttons
 353         }
 354         else
 355         {
 356             wxASSERT_MSG( wBtnOld == rc.right - rc.left,
 357                           "all buttons are supposed to be of same width" );
 358         }
 359
 360         const int widthNeeded = wxMSWButton::GetFittingSize(this, sizeLabel).x;
 361         if ( widthNeeded > wBtnNew )
 362             wBtnNew = widthNeeded;
 363
 364         ::SetWindowText(hwndBtn, label.wx_str());
 365     }
 366
 367     if ( wBtnNew <= wBtnOld )
 368     {
 369         // all buttons fit, nothing else to do
 370         return;
 371     }
 372
 373     // resize the message box to be wider if needed
 374     const int wBoxOld = wxGetClientRect(GetHwnd()).right;
 375
 376     const int CHAR_WIDTH = GetCharWidth();
 377     const int MARGIN_OUTER = 2*CHAR_WIDTH;  // margin between box and buttons
 378     const int MARGIN_INNER = CHAR_WIDTH;    // margin between buttons
 379
 380     RECT rcBox = wxGetWindowRect(GetHwnd());
 381
 382     const int wAllButtons = numButtons*(wBtnNew + MARGIN_INNER) - MARGIN_INNER;
 383     int wBoxNew = 2*MARGIN_OUTER + wAllButtons;
 384     if ( wBoxNew > wBoxOld )
 385     {
 386         const int dw = wBoxNew - wBoxOld;
 387         rcBox.left -= dw/2;
 388         rcBox.right += dw - dw/2;
 389
 390         SetWindowRect(GetHwnd(), rcBox);
 391
 392         // surprisingly, we don't need to resize the static text control, it
 393         // seems to adjust itself to the new size, at least under Windows 2003
 394         // (TODO: test if this happens on older Windows versions)
 395     }
 396     else // the current width is big enough
 397     {
 398         wBoxNew = wBoxOld;
 399     }
 400
 401
 402     // finally position all buttons
 403
 404     // notice that we have to take into account the difference between window
 405     // and client width
 406     rcBtn.left = (rcBox.left + rcBox.right - wxGetClientRect(GetHwnd()).right +
 407                   wBoxNew - wAllButtons) / 2;
 408     rcBtn.right = rcBtn.left + wBtnNew;
 409
 410     for ( n = 0; n < WXSIZEOF(ms_buttons); n++ )
 411     {
 412         const HWND hwndBtn = ::GetDlgItem(GetHwnd(), ms_buttons[n].id);
 413         if ( !hwndBtn )
 414             continue;
 415
 416         MoveWindowToScreenRect(hwndBtn, rcBtn);
 417
 418         rcBtn.left += wBtnNew + MARGIN_INNER;
 419         rcBtn.right += wBtnNew + MARGIN_INNER;
 420     }
 421 }
 422
 423 #endif // wxUSE_MSGBOX_HOOK
 424
 425 /* static */
 426 wxFont wxMessageDialog::GetMessageFont()
 427 {
 428     const NONCLIENTMETRICS& ncm = wxMSWImpl::GetNonClientMetrics();
 429     return wxNativeFontInfo(ncm.lfMessageFont);
 430 }
 431
 432 int wxMessageDialog::ShowModal()
 433 {
 434     if ( !wxTheApp->GetTopWindow() )
 435     {
 436         // when the message box is shown from wxApp::OnInit() (i.e. before the
 437         // message loop is entered), this must be done or the next message box
 438         // will never be shown - just try putting 2 calls to wxMessageBox() in
 439         // OnInit() to see it
 440         while ( wxTheApp->Pending() )
 441             wxTheApp->Dispatch();
 442     }
 443
 444     // use the top level window as parent if none specified
 445     if ( !m_parent )
 446         m_parent = GetParentForModalDialog();
 447     HWND hWnd = m_parent ? GetHwndOf(m_parent) : NULL;
 448
 449 #if wxUSE_INTL
 450     // native message box always uses the current user locale but the program
 451     // may be using a different one and in this case we need to manually
 452     // translate the button labels to avoid mismatch between the language of
 453     // the message box text and its buttons
 454     wxLocale * const loc = wxGetLocale();
 455     if ( loc && loc->GetLanguage() != wxLocale::GetSystemLanguage() )
 456     {
 457         if ( m_dialogStyle & wxYES_NO )
 458         {
 459             // use the strings with mnemonics here as the native message box
 460             // does
 461             SetYesNoLabels(_("&Yes"), _("&No"));
 462         }
 463
 464         // we may or not have the Ok/Cancel buttons but either we do have them
 465         // or we already made the labels custom because we called
 466         // SetYesNoLabels() above so doing this does no harm -- and is
 467         // necessary in wxYES_NO | wxCANCEL case
 468         //
 469         // note that we don't use mnemonics here for consistency with the
 470         // native message box (which probably doesn't use them because
 471         // Enter/Esc keys can be already used to dismiss the message box
 472         // using keyboard)
 473         SetOKCancelLabels(_("OK"), _("Cancel"));
 474     }
 475 #endif // wxUSE_INTL
 476
 477     // translate wx style in MSW
 478     unsigned int msStyle;
 479     const long wxStyle = GetMessageDialogStyle();
 480     if ( wxStyle & wxYES_NO )
 481     {
 482 #if !(defined(__SMARTPHONE__) && defined(__WXWINCE__))
 483         if (wxStyle & wxCANCEL)
 484             msStyle = MB_YESNOCANCEL;
 485         else
 486 #endif // !(__SMARTPHONE__ && __WXWINCE__)
 487             msStyle = MB_YESNO;
 488
 489         if ( wxStyle & wxNO_DEFAULT )
 490             msStyle |= MB_DEFBUTTON2;
 491         else if ( wxStyle & wxCANCEL_DEFAULT )
 492             msStyle |= MB_DEFBUTTON3;
 493     }
 494     else // without Yes/No we're going to have an OK button
 495     {
 496         if ( wxStyle & wxCANCEL )
 497         {
 498             msStyle = MB_OKCANCEL;
 499
 500             if ( wxStyle & wxCANCEL_DEFAULT )
 501                 msStyle |= MB_DEFBUTTON2;
 502         }
 503         else // just "OK"
 504         {
 505             msStyle = MB_OK;
 506         }
 507     }
 508
 509     if (wxStyle & wxICON_EXCLAMATION)
 510         msStyle |= MB_ICONEXCLAMATION;
 511     else if (wxStyle & wxICON_HAND)
 512         msStyle |= MB_ICONHAND;
 513     else if (wxStyle & wxICON_INFORMATION)
 514         msStyle |= MB_ICONINFORMATION;
 515     else if (wxStyle & wxICON_QUESTION)
 516         msStyle |= MB_ICONQUESTION;
 517
 518     if ( wxStyle & wxSTAY_ON_TOP )
 519         msStyle |= MB_TOPMOST;
 520
 521 #ifndef __WXWINCE__
 522     if ( wxTheApp->GetLayoutDirection() == wxLayout_RightToLeft )
 523         msStyle |= MB_RTLREADING | MB_RIGHT;
 524 #endif
 525
 526     if (hWnd)
 527         msStyle |= MB_APPLMODAL;
 528     else
 529         msStyle |= MB_TASKMODAL;
 530
 531     // per MSDN documentation for MessageBox() we can prefix the message with 2
 532     // right-to-left mark characters to tell the function to use RTL layout
 533     // (unfortunately this only works in Unicode builds)
 534     wxString message = GetFullMessage();
 535 #if wxUSE_UNICODE
 536     if ( wxTheApp->GetLayoutDirection() == wxLayout_RightToLeft )
 537     {
 538         // NB: not all compilers support \u escapes
 539         static const wchar_t wchRLM = 0x200f;
 540         message.Prepend(wxString(wchRLM, 2));
 541     }
 542 #endif // wxUSE_UNICODE
 543
 544 #if wxUSE_MSGBOX_HOOK
 545     // install the hook in any case as we don't know in advance if the message
 546     // box is not going to be too big (requiring the replacement of the static
 547     // control with an edit one)
 548     const DWORD tid = ::GetCurrentThreadId();
 549     m_hook = ::SetWindowsHookEx(WH_CBT,
 550                                 &wxMessageDialog::HookFunction, NULL, tid);
 551     HookMap()[tid] = this;
 552 #endif // wxUSE_MSGBOX_HOOK
 553
 554     // do show the dialog
 555     int msAns = MessageBox(hWnd, message.wx_str(), m_caption.wx_str(), msStyle);
 556     int ans;
 557     switch (msAns)
 558     {
 559         default:
 560             wxFAIL_MSG(_T("unexpected ::MessageBox() return code"));
 561             // fall through
 562
 563         case IDCANCEL:
 564             ans = wxID_CANCEL;
 565             break;
 566         case IDOK:
 567             ans = wxID_OK;
 568             break;
 569         case IDYES:
 570             ans = wxID_YES;
 571             break;
 572         case IDNO:
 573             ans = wxID_NO;
 574             break;
 575     }
 576     return ans;
 577 }
 578
 579 #endif // wxUSE_MSGDLG