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, wxT("STATIC"), NULL);
 205     if ( ::GetWindowLong(hwndStatic, GWL_STYLE) & SS_ICON )
 206         hwndStatic = ::FindWindowEx(GetHwnd(), hwndStatic, wxT("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::reverse_iterator i = text.rbegin(); i != text.rend(); ++i )
 250     {
 251         if ( *i != '\n' )
 252         {
 253             // found last non-newline char, remove everything after it and stop
 254             text.erase(i.base() + 1, text.end());
 255             break;
 256         }
 257     }
 258
 259     // do create the new control
 260     HWND hwndEdit = ::CreateWindow
 261                       (
 262                         wxT("EDIT"),
 263                         wxTextBuffer::Translate(text).wx_str(),
 264                         WS_CHILD | WS_VSCROLL | WS_VISIBLE |
 265                         ES_MULTILINE | ES_READONLY | ES_AUTOVSCROLL,
 266                         rc.left, rc.top,
 267                         rc.right - rc.left, rc.bottom - rc.top,
 268                         GetHwnd(),
 269                         NULL,
 270                         wxGetInstance(),
 271                         NULL
 272                       );
 273
 274     if ( !hwndEdit )
 275     {
 276         wxLogDebug("Creation of replacement edit control failed in message box");
 277         return;
 278     }
 279
 280     // copy the font from the original control
 281     LRESULT hfont = ::SendMessage(hwndStatic, WM_GETFONT, 0, 0);
 282     ::SendMessage(hwndEdit, WM_SETFONT, hfont, 0);
 283
 284     // and get rid of it
 285     ::DestroyWindow(hwndStatic);
 286
 287
 288     // shrink and centre the message box vertically and widen it box to account
 289     // for the extra scrollbar
 290     RECT rcBox = wxGetWindowRect(GetHwnd());
 291     const int hMsgBox = rcBox.bottom - rcBox.top - dh;
 292     rcBox.top = (rectDisplay.height - hMsgBox)/2;
 293     rcBox.bottom = rcBox.top + hMsgBox + (rectDisplay.height - hMsgBox)%2;
 294     rcBox.left -= dw/2;
 295     rcBox.right += dw - dw/2;
 296     SetWindowRect(GetHwnd(), rcBox);
 297
 298     // and adjust all the buttons positions
 299     for ( unsigned n = 0; n < WXSIZEOF(ms_buttons); n++ )
 300     {
 301         const HWND hwndBtn = ::GetDlgItem(GetHwnd(), ms_buttons[n].id);
 302         if ( !hwndBtn )
 303             continue;   // it's ok, not all buttons are always present
 304
 305         RECT rc = wxGetWindowRect(hwndBtn);
 306         rc.top -= dh;
 307         rc.bottom -= dh;
 308         rc.left += dw/2;
 309         rc.right += dw/2;
 310         MoveWindowToScreenRect(hwndBtn, rc);
 311     }
 312 }
 313
 314 void wxMessageDialog::AdjustButtonLabels()
 315 {
 316     // changing the button labels is the easy part but we also need to ensure
 317     // that the buttons are big enough for the label strings and increase their
 318     // size (and maybe the size of the message box itself) if they are not
 319
 320     // TODO-RTL: check whether this works correctly in RTL
 321
 322     // we want to use this font in GetTextExtent() calls below but we don't
 323     // want to send WM_SETFONT to the message box, who knows how is it going to
 324     // react to it (right now it doesn't seem to do anything but what if this
 325     // changes)
 326     wxWindowBase::SetFont(GetMessageFont());
 327
 328     // first iteration: find the widest button and update the buttons labels
 329     int wBtnOld = 0,            // current buttons width
 330         wBtnNew = 0;            // required new buttons width
 331     RECT rcBtn;                 // stores the button height and y positions
 332     unsigned numButtons = 0;    // total number of buttons in the message box
 333     unsigned n;
 334     for ( n = 0; n < WXSIZEOF(ms_buttons); n++ )
 335     {
 336         const HWND hwndBtn = ::GetDlgItem(GetHwnd(), ms_buttons[n].id);
 337         if ( !hwndBtn )
 338             continue;   // it's ok, not all buttons are always present
 339
 340         numButtons++;
 341
 342         const wxString label = (this->*ms_buttons[n].getter)();
 343         const wxSize sizeLabel = wxWindowBase::GetTextExtent(label);
 344
 345         // check if the button is big enough for this label
 346         const RECT rc = wxGetWindowRect(hwndBtn);
 347         if ( !wBtnOld )
 348         {
 349             // initialize wBtnOld using the first button width, all the other
 350             // ones should have the same one
 351             wBtnOld = rc.right - rc.left;
 352
 353             rcBtn = rc; // remember for use below when we reposition the buttons
 354         }
 355         else
 356         {
 357             wxASSERT_MSG( wBtnOld == rc.right - rc.left,
 358                           "all buttons are supposed to be of same width" );
 359         }
 360
 361         const int widthNeeded = wxMSWButton::GetFittingSize(this, sizeLabel).x;
 362         if ( widthNeeded > wBtnNew )
 363             wBtnNew = widthNeeded;
 364
 365         ::SetWindowText(hwndBtn, label.wx_str());
 366     }
 367
 368     if ( wBtnNew <= wBtnOld )
 369     {
 370         // all buttons fit, nothing else to do
 371         return;
 372     }
 373
 374     // resize the message box to be wider if needed
 375     const int wBoxOld = wxGetClientRect(GetHwnd()).right;
 376
 377     const int CHAR_WIDTH = GetCharWidth();
 378     const int MARGIN_OUTER = 2*CHAR_WIDTH;  // margin between box and buttons
 379     const int MARGIN_INNER = CHAR_WIDTH;    // margin between buttons
 380
 381     RECT rcBox = wxGetWindowRect(GetHwnd());
 382
 383     const int wAllButtons = numButtons*(wBtnNew + MARGIN_INNER) - MARGIN_INNER;
 384     int wBoxNew = 2*MARGIN_OUTER + wAllButtons;
 385     if ( wBoxNew > wBoxOld )
 386     {
 387         const int dw = wBoxNew - wBoxOld;
 388         rcBox.left -= dw/2;
 389         rcBox.right += dw - dw/2;
 390
 391         SetWindowRect(GetHwnd(), rcBox);
 392
 393         // surprisingly, we don't need to resize the static text control, it
 394         // seems to adjust itself to the new size, at least under Windows 2003
 395         // (TODO: test if this happens on older Windows versions)
 396     }
 397     else // the current width is big enough
 398     {
 399         wBoxNew = wBoxOld;
 400     }
 401
 402
 403     // finally position all buttons
 404
 405     // notice that we have to take into account the difference between window
 406     // and client width
 407     rcBtn.left = (rcBox.left + rcBox.right - wxGetClientRect(GetHwnd()).right +
 408                   wBoxNew - wAllButtons) / 2;
 409     rcBtn.right = rcBtn.left + wBtnNew;
 410
 411     for ( n = 0; n < WXSIZEOF(ms_buttons); n++ )
 412     {
 413         const HWND hwndBtn = ::GetDlgItem(GetHwnd(), ms_buttons[n].id);
 414         if ( !hwndBtn )
 415             continue;
 416
 417         MoveWindowToScreenRect(hwndBtn, rcBtn);
 418
 419         rcBtn.left += wBtnNew + MARGIN_INNER;
 420         rcBtn.right += wBtnNew + MARGIN_INNER;
 421     }
 422 }
 423
 424 #endif // wxUSE_MSGBOX_HOOK
 425
 426 /* static */
 427 wxFont wxMessageDialog::GetMessageFont()
 428 {
 429     const NONCLIENTMETRICS& ncm = wxMSWImpl::GetNonClientMetrics();
 430     return wxNativeFontInfo(ncm.lfMessageFont);
 431 }
 432
 433 int wxMessageDialog::ShowModal()
 434 {
 435     if ( !wxTheApp->GetTopWindow() )
 436     {
 437         // when the message box is shown from wxApp::OnInit() (i.e. before the
 438         // message loop is entered), this must be done or the next message box
 439         // will never be shown - just try putting 2 calls to wxMessageBox() in
 440         // OnInit() to see it
 441         while ( wxTheApp->Pending() )
 442             wxTheApp->Dispatch();
 443     }
 444
 445     // use the top level window as parent if none specified
 446     if ( !m_parent )
 447         m_parent = GetParentForModalDialog();
 448     HWND hWnd = m_parent ? GetHwndOf(m_parent) : NULL;
 449
 450 #if wxUSE_INTL
 451     // native message box always uses the current user locale but the program
 452     // may be using a different one and in this case we need to manually
 453     // translate the button labels to avoid mismatch between the language of
 454     // the message box text and its buttons
 455     wxLocale * const loc = wxGetLocale();
 456     if ( loc && loc->GetLanguage() != wxLocale::GetSystemLanguage() )
 457     {
 458         if ( m_dialogStyle & wxYES_NO )
 459         {
 460             // use the strings with mnemonics here as the native message box
 461             // does
 462             SetYesNoLabels(_("&Yes"), _("&No"));
 463         }
 464
 465         // we may or not have the Ok/Cancel buttons but either we do have them
 466         // or we already made the labels custom because we called
 467         // SetYesNoLabels() above so doing this does no harm -- and is
 468         // necessary in wxYES_NO | wxCANCEL case
 469         //
 470         // note that we don't use mnemonics here for consistency with the
 471         // native message box (which probably doesn't use them because
 472         // Enter/Esc keys can be already used to dismiss the message box
 473         // using keyboard)
 474         SetOKCancelLabels(_("OK"), _("Cancel"));
 475     }
 476 #endif // wxUSE_INTL
 477
 478     // translate wx style in MSW
 479     unsigned int msStyle;
 480     const long wxStyle = GetMessageDialogStyle();
 481     if ( wxStyle & wxYES_NO )
 482     {
 483 #if !(defined(__SMARTPHONE__) && defined(__WXWINCE__))
 484         if (wxStyle & wxCANCEL)
 485             msStyle = MB_YESNOCANCEL;
 486         else
 487 #endif // !(__SMARTPHONE__ && __WXWINCE__)
 488             msStyle = MB_YESNO;
 489
 490         if ( wxStyle & wxNO_DEFAULT )
 491             msStyle |= MB_DEFBUTTON2;
 492         else if ( wxStyle & wxCANCEL_DEFAULT )
 493             msStyle |= MB_DEFBUTTON3;
 494     }
 495     else // without Yes/No we're going to have an OK button
 496     {
 497         if ( wxStyle & wxCANCEL )
 498         {
 499             msStyle = MB_OKCANCEL;
 500
 501             if ( wxStyle & wxCANCEL_DEFAULT )
 502                 msStyle |= MB_DEFBUTTON2;
 503         }
 504         else // just "OK"
 505         {
 506             msStyle = MB_OK;
 507         }
 508     }
 509
 510     if (wxStyle & wxICON_EXCLAMATION)
 511         msStyle |= MB_ICONEXCLAMATION;
 512     else if (wxStyle & wxICON_HAND)
 513         msStyle |= MB_ICONHAND;
 514     else if (wxStyle & wxICON_INFORMATION)
 515         msStyle |= MB_ICONINFORMATION;
 516     else if (wxStyle & wxICON_QUESTION)
 517         msStyle |= MB_ICONQUESTION;
 518
 519     if ( wxStyle & wxSTAY_ON_TOP )
 520         msStyle |= MB_TOPMOST;
 521
 522 #ifndef __WXWINCE__
 523     if ( wxTheApp->GetLayoutDirection() == wxLayout_RightToLeft )
 524         msStyle |= MB_RTLREADING | MB_RIGHT;
 525 #endif
 526
 527     if (hWnd)
 528         msStyle |= MB_APPLMODAL;
 529     else
 530         msStyle |= MB_TASKMODAL;
 531
 532     // per MSDN documentation for MessageBox() we can prefix the message with 2
 533     // right-to-left mark characters to tell the function to use RTL layout
 534     // (unfortunately this only works in Unicode builds)
 535     wxString message = GetFullMessage();
 536 #if wxUSE_UNICODE
 537     if ( wxTheApp->GetLayoutDirection() == wxLayout_RightToLeft )
 538     {
 539         // NB: not all compilers support \u escapes
 540         static const wchar_t wchRLM = 0x200f;
 541         message.Prepend(wxString(wchRLM, 2));
 542     }
 543 #endif // wxUSE_UNICODE
 544
 545 #if wxUSE_MSGBOX_HOOK
 546     // install the hook in any case as we don't know in advance if the message
 547     // box is not going to be too big (requiring the replacement of the static
 548     // control with an edit one)
 549     const DWORD tid = ::GetCurrentThreadId();
 550     m_hook = ::SetWindowsHookEx(WH_CBT,
 551                                 &wxMessageDialog::HookFunction, NULL, tid);
 552     HookMap()[tid] = this;
 553 #endif // wxUSE_MSGBOX_HOOK
 554
 555     // do show the dialog
 556     int msAns = MessageBox(hWnd, message.wx_str(), m_caption.wx_str(), msStyle);
 557     int ans;
 558     switch (msAns)
 559     {
 560         default:
 561             wxFAIL_MSG(wxT("unexpected ::MessageBox() return code"));
 562             // fall through
 563
 564         case IDCANCEL:
 565             ans = wxID_CANCEL;
 566             break;
 567         case IDOK:
 568             ans = wxID_OK;
 569             break;
 570         case IDYES:
 571             ans = wxID_YES;
 572             break;
 573         case IDNO:
 574             ans = wxID_NO;
 575             break;
 576     }
 577     return ans;
 578 }
 579
 580 #endif // wxUSE_MSGDLG