src/generic/scrlwing.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        generic/scrolwin.cpp
   3 // Purpose:     wxGenericScrolledWindow implementation
   4 // Author:      Julian Smart
   5 // Modified by: Vadim Zeitlin on 31.08.00: wxScrollHelper allows to implement
   6 // Created:     01/02/97
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) wxWindows team
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #ifdef __GNUG__
  21     #pragma implementation "genscrolwin.h"
  22 #endif
  23
  24 #ifdef __VMS
  25 #define XtDisplay XTDISPLAY
  26 #endif
  27
  28 // For compilers that support precompilation, includes "wx.h".
  29 #include "wx/wxprec.h"
  30
  31 #ifdef __BORLANDC__
  32     #pragma hdrstop
  33 #endif
  34
  35 #if !defined(__WXGTK__) || defined(__WXUNIVERSAL__)
  36
  37 #include "wx/utils.h"
  38 #include "wx/dcclient.h"
  39
  40 #include "wx/scrolwin.h"
  41 #include "wx/panel.h"
  42 #include "wx/timer.h"
  43
  44 #ifdef __WXMSW__
  45     #include <windows.h> // for DLGC_WANTARROWS
  46 #endif
  47
  48 #ifdef __WXMOTIF__
  49 // For wxRETAINED implementation
  50 #ifdef __VMS__ //VMS's Xm.h is not (yet) compatible with C++
  51                //This code switches off the compiler warnings
  52 # pragma message disable nosimpint
  53 #endif
  54 #include <Xm/Xm.h>
  55 #ifdef __VMS__
  56 # pragma message enable nosimpint
  57 #endif
  58 #endif
  59
  60 IMPLEMENT_CLASS(wxScrolledWindow, wxGenericScrolledWindow)
  61
  62 // ----------------------------------------------------------------------------
  63 // wxScrollHelperEvtHandler: intercept the events from the window and forward
  64 // them to wxScrollHelper
  65 // ----------------------------------------------------------------------------
  66
  67 class WXDLLEXPORT wxScrollHelperEvtHandler : public wxEvtHandler
  68 {
  69 public:
  70     wxScrollHelperEvtHandler(wxScrollHelper *scrollHelper)
  71     {
  72         m_scrollHelper = scrollHelper;
  73     }
  74
  75     virtual bool ProcessEvent(wxEvent& event);
  76
  77     void ResetDrawnFlag() { m_hasDrawnWindow = FALSE; }
  78
  79 private:
  80     wxScrollHelper *m_scrollHelper;
  81
  82     bool m_hasDrawnWindow;
  83 };
  84
  85 // ----------------------------------------------------------------------------
  86 // wxAutoScrollTimer: the timer used to generate a stream of scroll events when
  87 // a captured mouse is held outside the window
  88 // ----------------------------------------------------------------------------
  89
  90 class wxAutoScrollTimer : public wxTimer
  91 {
  92 public:
  93     wxAutoScrollTimer(wxWindow *winToScroll, wxScrollHelper *scroll,
  94                       wxEventType eventTypeToSend,
  95                       int pos, int orient);
  96
  97     virtual void Notify();
  98
  99 private:
 100     wxWindow *m_win;
 101     wxScrollHelper *m_scrollHelper;
 102     wxEventType m_eventType;
 103     int m_pos,
 104         m_orient;
 105 };
 106
 107 // ============================================================================
 108 // implementation
 109 // ============================================================================
 110
 111 // ----------------------------------------------------------------------------
 112 // wxAutoScrollTimer
 113 // ----------------------------------------------------------------------------
 114
 115 wxAutoScrollTimer::wxAutoScrollTimer(wxWindow *winToScroll,
 116                                      wxScrollHelper *scroll,
 117                                      wxEventType eventTypeToSend,
 118                                      int pos, int orient)
 119 {
 120     m_win = winToScroll;
 121     m_scrollHelper = scroll;
 122     m_eventType = eventTypeToSend;
 123     m_pos = pos;
 124     m_orient = orient;
 125 }
 126
 127 void wxAutoScrollTimer::Notify()
 128 {
 129     // only do all this as long as the window is capturing the mouse
 130     if ( wxWindow::GetCapture() != m_win )
 131     {
 132         Stop();
 133     }
 134     else // we still capture the mouse, continue generating events
 135     {
 136         // first scroll the window if we are allowed to do it
 137         wxScrollWinEvent event1(m_eventType, m_pos, m_orient);
 138         event1.SetEventObject(m_win);
 139         if ( m_scrollHelper->SendAutoScrollEvents(event1) &&
 140                 m_win->GetEventHandler()->ProcessEvent(event1) )
 141         {
 142             // and then send a pseudo mouse-move event to refresh the selection
 143             wxMouseEvent event2(wxEVT_MOTION);
 144             wxGetMousePosition(&event2.m_x, &event2.m_y);
 145
 146             // the mouse event coordinates should be client, not screen as
 147             // returned by wxGetMousePosition
 148             wxWindow *parentTop = m_win;
 149             while ( parentTop->GetParent() )
 150                 parentTop = parentTop->GetParent();
 151             wxPoint ptOrig = parentTop->GetPosition();
 152             event2.m_x -= ptOrig.x;
 153             event2.m_y -= ptOrig.y;
 154
 155             event2.SetEventObject(m_win);
 156
 157             // FIXME: we don't fill in the other members - ok?
 158
 159             m_win->GetEventHandler()->ProcessEvent(event2);
 160         }
 161         else // can't scroll further, stop
 162         {
 163             Stop();
 164         }
 165     }
 166 }
 167
 168 // ----------------------------------------------------------------------------
 169 // wxScrollHelperEvtHandler
 170 // ----------------------------------------------------------------------------
 171
 172 bool wxScrollHelperEvtHandler::ProcessEvent(wxEvent& event)
 173 {
 174     wxEventType evType = event.GetEventType();
 175
 176     // the explanation of wxEVT_PAINT processing hack: for historic reasons
 177     // there are 2 ways to process this event in classes deriving from
 178     // wxScrolledWindow. The user code may
 179     //
 180     //  1. override wxScrolledWindow::OnDraw(dc)
 181     //  2. define its own OnPaint() handler
 182     //
 183     // In addition, in wxUniversal wxWindow defines OnPaint() itself and
 184     // always processes the draw event, so we can't just try the window
 185     // OnPaint() first and call our HandleOnPaint() if it doesn't process it
 186     // (the latter would never be called in wxUniversal).
 187     //
 188     // So the solution is to have a flag telling us whether the user code drew
 189     // anything in the window. We set it to true here but reset it to false in
 190     // wxScrolledWindow::OnPaint() handler (which wouldn't be called if the
 191     // user code defined OnPaint() in the derived class)
 192     m_hasDrawnWindow = TRUE;
 193
 194     // pass it on to the real handler
 195     bool processed = wxEvtHandler::ProcessEvent(event);
 196
 197     // always process the size events ourselves, even if the user code handles
 198     // them as well, as we need to AdjustScrollbars()
 199     //
 200     // NB: it is important to do it after processing the event in the normal
 201     //     way as HandleOnSize() may generate a wxEVT_SIZE itself if the
 202     //     scrollbar[s] (dis)appear and it should be seen by the user code
 203     //     after this one
 204     if ( evType == wxEVT_SIZE )
 205     {
 206         m_scrollHelper->HandleOnSize((wxSizeEvent &)event);
 207
 208         return TRUE;
 209     }
 210
 211     if ( processed )
 212     {
 213         // normally, nothing more to do here - except if it was a paint event
 214         // which wasn't really processed, then we'll try to call our
 215         // OnDraw() below (from HandleOnPaint)
 216         if ( m_hasDrawnWindow )
 217         {
 218             return TRUE;
 219         }
 220     }
 221
 222     // reset the skipped flag to FALSE as it might have been set to TRUE in
 223     // ProcessEvent() above
 224     event.Skip(FALSE);
 225
 226     if ( evType == wxEVT_PAINT )
 227     {
 228         m_scrollHelper->HandleOnPaint((wxPaintEvent &)event);
 229         return TRUE;
 230     }
 231
 232     if ( evType == wxEVT_SCROLLWIN_TOP ||
 233          evType == wxEVT_SCROLLWIN_BOTTOM ||
 234          evType == wxEVT_SCROLLWIN_LINEUP ||
 235          evType == wxEVT_SCROLLWIN_LINEDOWN ||
 236          evType == wxEVT_SCROLLWIN_PAGEUP ||
 237          evType == wxEVT_SCROLLWIN_PAGEDOWN ||
 238          evType == wxEVT_SCROLLWIN_THUMBTRACK ||
 239          evType == wxEVT_SCROLLWIN_THUMBRELEASE )
 240     {
 241             m_scrollHelper->HandleOnScroll((wxScrollWinEvent &)event);
 242             return !event.GetSkipped();
 243     }
 244
 245     if ( evType == wxEVT_ENTER_WINDOW )
 246     {
 247         m_scrollHelper->HandleOnMouseEnter((wxMouseEvent &)event);
 248     }
 249     else if ( evType == wxEVT_LEAVE_WINDOW )
 250     {
 251         m_scrollHelper->HandleOnMouseLeave((wxMouseEvent &)event);
 252     }
 253 #if wxUSE_MOUSEWHEEL
 254     else if ( evType == wxEVT_MOUSEWHEEL )
 255     {
 256         m_scrollHelper->HandleOnMouseWheel((wxMouseEvent &)event);
 257     }
 258 #endif // wxUSE_MOUSEWHEEL
 259     else if ( evType == wxEVT_CHAR )
 260     {
 261         m_scrollHelper->HandleOnChar((wxKeyEvent &)event);
 262         return !event.GetSkipped();
 263     }
 264
 265     return FALSE;
 266 }
 267
 268 // ----------------------------------------------------------------------------
 269 // wxScrollHelper construction
 270 // ----------------------------------------------------------------------------
 271
 272 wxScrollHelper::wxScrollHelper(wxWindow *win)
 273 {
 274     m_xScrollPixelsPerLine =
 275     m_yScrollPixelsPerLine =
 276     m_xScrollPosition =
 277     m_yScrollPosition =
 278     m_xScrollLines =
 279     m_yScrollLines =
 280     m_xScrollLinesPerPage =
 281     m_yScrollLinesPerPage = 0;
 282
 283     m_xScrollingEnabled =
 284     m_yScrollingEnabled = TRUE;
 285
 286     m_scaleX =
 287     m_scaleY = 1.0;
 288 #if wxUSE_MOUSEWHEEL
 289     m_wheelRotation = 0;
 290 #endif
 291
 292     m_win =
 293     m_targetWindow = (wxWindow *)NULL;
 294
 295     m_timerAutoScroll = (wxTimer *)NULL;
 296
 297     m_handler = NULL;
 298
 299     if ( win )
 300         SetWindow(win);
 301 }
 302
 303 wxScrollHelper::~wxScrollHelper()
 304 {
 305     StopAutoScrolling();
 306
 307     DeleteEvtHandler();
 308 }
 309
 310 // ----------------------------------------------------------------------------
 311 // setting scrolling parameters
 312 // ----------------------------------------------------------------------------
 313
 314 void wxScrollHelper::SetScrollbars(int pixelsPerUnitX,
 315                                    int pixelsPerUnitY,
 316                                    int noUnitsX,
 317                                    int noUnitsY,
 318                                    int xPos,
 319                                    int yPos,
 320                                    bool noRefresh)
 321 {
 322     int xpos, ypos;
 323
 324     CalcUnscrolledPosition(xPos, yPos, &xpos, &ypos);
 325     bool do_refresh =
 326     (
 327       (noUnitsX != 0 && m_xScrollLines == 0) ||
 328       (noUnitsX < m_xScrollLines && xpos > pixelsPerUnitX*noUnitsX) ||
 329
 330       (noUnitsY != 0 && m_yScrollLines == 0) ||
 331       (noUnitsY < m_yScrollLines && ypos > pixelsPerUnitY*noUnitsY) ||
 332       (xPos != m_xScrollPosition) ||
 333       (yPos != m_yScrollPosition)
 334     );
 335
 336     m_xScrollPixelsPerLine = pixelsPerUnitX;
 337     m_yScrollPixelsPerLine = pixelsPerUnitY;
 338     m_xScrollPosition = xPos;
 339     m_yScrollPosition = yPos;
 340     m_xScrollLines = noUnitsX;
 341     m_yScrollLines = noUnitsY;
 342
 343 #ifdef __WXMOTIF__
 344     // Sorry, some Motif-specific code to implement a backing pixmap
 345     // for the wxRETAINED style. Implementing a backing store can't
 346     // be entirely generic because it relies on the wxWindowDC implementation
 347     // to duplicate X drawing calls for the backing pixmap.
 348
 349     if ( m_targetWindow->GetWindowStyle() & wxRETAINED )
 350     {
 351         Display* dpy = XtDisplay((Widget)m_targetWindow->GetMainWidget());
 352
 353         int totalPixelWidth = m_xScrollLines * m_xScrollPixelsPerLine;
 354         int totalPixelHeight = m_yScrollLines * m_yScrollPixelsPerLine;
 355         if (m_targetWindow->GetBackingPixmap() &&
 356            !((m_targetWindow->GetPixmapWidth() == totalPixelWidth) &&
 357              (m_targetWindow->GetPixmapHeight() == totalPixelHeight)))
 358         {
 359             XFreePixmap (dpy, (Pixmap) m_targetWindow->GetBackingPixmap());
 360             m_targetWindow->SetBackingPixmap((WXPixmap) 0);
 361         }
 362
 363         if (!m_targetWindow->GetBackingPixmap() &&
 364            (noUnitsX != 0) && (noUnitsY != 0))
 365         {
 366             int depth = wxDisplayDepth();
 367             m_targetWindow->SetPixmapWidth(totalPixelWidth);
 368             m_targetWindow->SetPixmapHeight(totalPixelHeight);
 369             m_targetWindow->SetBackingPixmap((WXPixmap) XCreatePixmap (dpy, RootWindow (dpy, DefaultScreen (dpy)),
 370               m_targetWindow->GetPixmapWidth(), m_targetWindow->GetPixmapHeight(), depth));
 371         }
 372
 373     }
 374 #endif // Motif
 375
 376     AdjustScrollbars();
 377
 378     if (do_refresh && !noRefresh)
 379         m_targetWindow->Refresh(TRUE, GetRect());
 380
 381 #ifdef __WXMAC__
 382     m_targetWindow->MacUpdateImmediately() ;
 383 #endif
 384 }
 385
 386 // ----------------------------------------------------------------------------
 387 // [target] window handling
 388 // ----------------------------------------------------------------------------
 389
 390 void wxScrollHelper::DeleteEvtHandler()
 391 {
 392     // search for m_handler in the handler list
 393     if ( m_win && m_handler )
 394     {
 395         wxEvtHandler *handlerPrev = NULL,
 396                      *handler = m_win->GetEventHandler();
 397         while ( handler )
 398         {
 399             if ( handler == m_handler )
 400             {
 401                 wxEvtHandler *handlerNext = handler->GetNextHandler();
 402                 if ( handlerPrev )
 403                 {
 404                     handlerPrev->SetNextHandler(handlerNext);
 405                 }
 406                 else
 407                 {
 408                     m_win->SetEventHandler(handlerNext);
 409                 }
 410
 411                 handler->SetNextHandler(NULL);
 412                 delete handler;
 413                 m_handler = NULL;
 414
 415                 return;
 416             }
 417
 418             handlerPrev = handler;
 419             handler = handler->GetNextHandler();
 420         }
 421
 422         wxFAIL_MSG( _T("where has our event handler gone?") );
 423     }
 424 }
 425
 426 void wxScrollHelper::SetWindow(wxWindow *win)
 427 {
 428     wxCHECK_RET( win, _T("wxScrollHelper needs a window to scroll") );
 429
 430     m_win = win;
 431
 432     // by default, the associated window is also the target window
 433     DoSetTargetWindow(win);
 434 }
 435
 436 void wxScrollHelper::DoSetTargetWindow(wxWindow *target)
 437 {
 438     m_targetWindow = target;
 439
 440     // install the event handler which will intercept the events we're
 441     // interested in (but only do it for our real window, not the target window
 442     // which we scroll - we don't need to hijack its events)
 443     if ( m_targetWindow == m_win )
 444     {
 445         // if we already have a handler, delete it first
 446         DeleteEvtHandler();
 447
 448         m_handler = new wxScrollHelperEvtHandler(this);
 449         m_targetWindow->PushEventHandler(m_handler);
 450     }
 451 }
 452
 453 void wxScrollHelper::SetTargetWindow(wxWindow *target)
 454 {
 455     wxCHECK_RET( target, wxT("target window must not be NULL") );
 456
 457     if ( target == m_targetWindow )
 458         return;
 459
 460     DoSetTargetWindow(target);
 461 }
 462
 463 wxWindow *wxScrollHelper::GetTargetWindow() const
 464 {
 465     return m_targetWindow;
 466 }
 467
 468 // ----------------------------------------------------------------------------
 469 // scrolling implementation itself
 470 // ----------------------------------------------------------------------------
 471
 472 void wxScrollHelper::HandleOnScroll(wxScrollWinEvent& event)
 473 {
 474     int nScrollInc = CalcScrollInc(event);
 475     if ( nScrollInc == 0 )
 476     {
 477         // can't scroll further
 478         event.Skip();
 479
 480         return;
 481     }
 482
 483     int orient = event.GetOrientation();
 484     if (orient == wxHORIZONTAL)
 485     {
 486         m_xScrollPosition += nScrollInc;
 487         m_win->SetScrollPos(wxHORIZONTAL, m_xScrollPosition);
 488     }
 489     else
 490     {
 491         m_yScrollPosition += nScrollInc;
 492         m_win->SetScrollPos(wxVERTICAL, m_yScrollPosition);
 493     }
 494
 495     bool needsRefresh = FALSE;
 496     int dx = 0,
 497         dy = 0;
 498     if (orient == wxHORIZONTAL)
 499     {
 500        if ( m_xScrollingEnabled )
 501        {
 502            dx = -m_xScrollPixelsPerLine * nScrollInc;
 503        }
 504        else
 505        {
 506            needsRefresh = TRUE;
 507        }
 508     }
 509     else
 510     {
 511         if ( m_yScrollingEnabled )
 512         {
 513             dy = -m_yScrollPixelsPerLine * nScrollInc;
 514         }
 515         else
 516         {
 517             needsRefresh = TRUE;
 518         }
 519     }
 520
 521     if ( needsRefresh )
 522     {
 523         m_targetWindow->Refresh(TRUE, GetRect());
 524     }
 525     else
 526     {
 527         m_targetWindow->ScrollWindow(dx, dy, GetRect());
 528     }
 529
 530 #ifdef __WXMAC__
 531     m_targetWindow->MacUpdateImmediately() ;
 532 #endif
 533 }
 534
 535 int wxScrollHelper::CalcScrollInc(wxScrollWinEvent& event)
 536 {
 537     int pos = event.GetPosition();
 538     int orient = event.GetOrientation();
 539
 540     int nScrollInc = 0;
 541     if (event.GetEventType() == wxEVT_SCROLLWIN_TOP)
 542     {
 543             if (orient == wxHORIZONTAL)
 544                 nScrollInc = - m_xScrollPosition;
 545             else
 546                 nScrollInc = - m_yScrollPosition;
 547     } else
 548     if (event.GetEventType() == wxEVT_SCROLLWIN_BOTTOM)
 549     {
 550             if (orient == wxHORIZONTAL)
 551                 nScrollInc = m_xScrollLines - m_xScrollPosition;
 552             else
 553                 nScrollInc = m_yScrollLines - m_yScrollPosition;
 554     } else
 555     if (event.GetEventType() == wxEVT_SCROLLWIN_LINEUP)
 556     {
 557             nScrollInc = -1;
 558     } else
 559     if (event.GetEventType() == wxEVT_SCROLLWIN_LINEDOWN)
 560     {
 561             nScrollInc = 1;
 562     } else
 563     if (event.GetEventType() == wxEVT_SCROLLWIN_PAGEUP)
 564     {
 565             if (orient == wxHORIZONTAL)
 566                 nScrollInc = -GetScrollPageSize(wxHORIZONTAL);
 567             else
 568                 nScrollInc = -GetScrollPageSize(wxVERTICAL);
 569     } else
 570     if (event.GetEventType() == wxEVT_SCROLLWIN_PAGEDOWN)
 571     {
 572             if (orient == wxHORIZONTAL)
 573                 nScrollInc = GetScrollPageSize(wxHORIZONTAL);
 574             else
 575                 nScrollInc = GetScrollPageSize(wxVERTICAL);
 576     } else
 577     if ((event.GetEventType() == wxEVT_SCROLLWIN_THUMBTRACK) ||
 578         (event.GetEventType() == wxEVT_SCROLLWIN_THUMBRELEASE))
 579     {
 580             if (orient == wxHORIZONTAL)
 581                 nScrollInc = pos - m_xScrollPosition;
 582             else
 583                 nScrollInc = pos - m_yScrollPosition;
 584     }
 585
 586     if (orient == wxHORIZONTAL)
 587     {
 588         if (m_xScrollPixelsPerLine > 0)
 589         {
 590             int w, h;
 591             GetTargetSize(&w, &h);
 592
 593             int nMaxWidth = m_xScrollLines*m_xScrollPixelsPerLine;
 594             int noPositions = (int) ( ((nMaxWidth - w)/(double)m_xScrollPixelsPerLine) + 0.5 );
 595             if (noPositions < 0)
 596                 noPositions = 0;
 597
 598             if ( (m_xScrollPosition + nScrollInc) < 0 )
 599                 nScrollInc = -m_xScrollPosition; // As -ve as we can go
 600             else if ( (m_xScrollPosition + nScrollInc) > noPositions )
 601                 nScrollInc = noPositions - m_xScrollPosition; // As +ve as we can go
 602         }
 603         else
 604             m_targetWindow->Refresh(TRUE, GetRect());
 605     }
 606     else
 607     {
 608         if (m_yScrollPixelsPerLine > 0)
 609         {
 610             int w, h;
 611             GetTargetSize(&w, &h);
 612
 613             int nMaxHeight = m_yScrollLines*m_yScrollPixelsPerLine;
 614             int noPositions = (int) ( ((nMaxHeight - h)/(double)m_yScrollPixelsPerLine) + 0.5 );
 615             if (noPositions < 0)
 616                 noPositions = 0;
 617
 618             if ( (m_yScrollPosition + nScrollInc) < 0 )
 619                 nScrollInc = -m_yScrollPosition; // As -ve as we can go
 620             else if ( (m_yScrollPosition + nScrollInc) > noPositions )
 621                 nScrollInc = noPositions - m_yScrollPosition; // As +ve as we can go
 622         }
 623         else
 624             m_targetWindow->Refresh(TRUE, GetRect());
 625     }
 626
 627     return nScrollInc;
 628 }
 629
 630 // Adjust the scrollbars - new version.
 631 void wxScrollHelper::AdjustScrollbars()
 632 {
 633 #ifdef __WXMAC__
 634     m_targetWindow->MacUpdateImmediately();
 635 #endif
 636
 637     int w, h;
 638     GetTargetSize(&w, &h);
 639
 640     int oldXScroll = m_xScrollPosition;
 641     int oldYScroll = m_yScrollPosition;
 642
 643     if (m_xScrollLines > 0)
 644     {
 645         // Calculate page size i.e. number of scroll units you get on the
 646         // current client window
 647         int noPagePositions = (int) ( (w/(double)m_xScrollPixelsPerLine) + 0.5 );
 648         if (noPagePositions < 1) noPagePositions = 1;
 649         if ( noPagePositions > m_xScrollLines )
 650             noPagePositions = m_xScrollLines;
 651
 652         // Correct position if greater than extent of canvas minus
 653         // the visible portion of it or if below zero
 654         m_xScrollPosition = wxMin( m_xScrollLines-noPagePositions, m_xScrollPosition);
 655         m_xScrollPosition = wxMax( 0, m_xScrollPosition );
 656
 657         m_win->SetScrollbar(wxHORIZONTAL, m_xScrollPosition, noPagePositions, m_xScrollLines);
 658         // The amount by which we scroll when paging
 659         SetScrollPageSize(wxHORIZONTAL, noPagePositions);
 660     }
 661     else
 662     {
 663         m_xScrollPosition = 0;
 664         m_win->SetScrollbar (wxHORIZONTAL, 0, 0, 0, FALSE);
 665     }
 666
 667     if (m_yScrollLines > 0)
 668     {
 669         // Calculate page size i.e. number of scroll units you get on the
 670         // current client window
 671         int noPagePositions = (int) ( (h/(double)m_yScrollPixelsPerLine) + 0.5 );
 672         if (noPagePositions < 1) noPagePositions = 1;
 673         if ( noPagePositions > m_yScrollLines )
 674             noPagePositions = m_yScrollLines;
 675
 676         // Correct position if greater than extent of canvas minus
 677         // the visible portion of it or if below zero
 678         m_yScrollPosition = wxMin( m_yScrollLines-noPagePositions, m_yScrollPosition );
 679         m_yScrollPosition = wxMax( 0, m_yScrollPosition );
 680
 681         m_win->SetScrollbar(wxVERTICAL, m_yScrollPosition, noPagePositions, m_yScrollLines);
 682         // The amount by which we scroll when paging
 683         SetScrollPageSize(wxVERTICAL, noPagePositions);
 684     }
 685     else
 686     {
 687         m_yScrollPosition = 0;
 688         m_win->SetScrollbar (wxVERTICAL, 0, 0, 0, FALSE);
 689     }
 690
 691     if (oldXScroll != m_xScrollPosition)
 692     {
 693        if (m_xScrollingEnabled)
 694             m_targetWindow->ScrollWindow( m_xScrollPixelsPerLine * (oldXScroll-m_xScrollPosition), 0,
 695                                           GetRect() );
 696        else
 697             m_targetWindow->Refresh(TRUE, GetRect());
 698     }
 699
 700     if (oldYScroll != m_yScrollPosition)
 701     {
 702         if (m_yScrollingEnabled)
 703             m_targetWindow->ScrollWindow( 0, m_yScrollPixelsPerLine * (oldYScroll-m_yScrollPosition),
 704                                           GetRect() );
 705         else
 706             m_targetWindow->Refresh(TRUE, GetRect());
 707     }
 708
 709 #ifdef __WXMAC__
 710     m_targetWindow->MacUpdateImmediately();
 711 #endif
 712 }
 713
 714 void wxScrollHelper::DoPrepareDC(wxDC& dc)
 715 {
 716     wxPoint pt = dc.GetDeviceOrigin();
 717     dc.SetDeviceOrigin( pt.x - m_xScrollPosition * m_xScrollPixelsPerLine,
 718                         pt.y - m_yScrollPosition * m_yScrollPixelsPerLine );
 719     dc.SetUserScale( m_scaleX, m_scaleY );
 720 }
 721
 722 void wxScrollHelper::GetScrollPixelsPerUnit (int *x_unit, int *y_unit) const
 723 {
 724     if ( x_unit )
 725         *x_unit = m_xScrollPixelsPerLine;
 726     if ( y_unit )
 727         *y_unit = m_yScrollPixelsPerLine;
 728 }
 729
 730 int wxScrollHelper::GetScrollPageSize(int orient) const
 731 {
 732     if ( orient == wxHORIZONTAL )
 733         return m_xScrollLinesPerPage;
 734     else
 735         return m_yScrollLinesPerPage;
 736 }
 737
 738 void wxScrollHelper::SetScrollPageSize(int orient, int pageSize)
 739 {
 740     if ( orient == wxHORIZONTAL )
 741         m_xScrollLinesPerPage = pageSize;
 742     else
 743         m_yScrollLinesPerPage = pageSize;
 744 }
 745
 746 /*
 747  * Scroll to given position (scroll position, not pixel position)
 748  */
 749 void wxScrollHelper::Scroll( int x_pos, int y_pos )
 750 {
 751     if (!m_targetWindow)
 752         return;
 753
 754     if (((x_pos == -1) || (x_pos == m_xScrollPosition)) &&
 755         ((y_pos == -1) || (y_pos == m_yScrollPosition))) return;
 756
 757 #ifdef __WXMAC__
 758     m_targetWindow->MacUpdateImmediately();
 759 #endif
 760
 761     int w, h;
 762     GetTargetSize(&w, &h);
 763
 764     if ((x_pos != -1) && (m_xScrollPixelsPerLine))
 765     {
 766         int old_x = m_xScrollPosition;
 767         m_xScrollPosition = x_pos;
 768
 769         // Calculate page size i.e. number of scroll units you get on the
 770         // current client window
 771         int noPagePositions = (int) ( (w/(double)m_xScrollPixelsPerLine) + 0.5 );
 772         if (noPagePositions < 1) noPagePositions = 1;
 773
 774         // Correct position if greater than extent of canvas minus
 775         // the visible portion of it or if below zero
 776         m_xScrollPosition = wxMin( m_xScrollLines-noPagePositions, m_xScrollPosition );
 777         m_xScrollPosition = wxMax( 0, m_xScrollPosition );
 778
 779         if (old_x != m_xScrollPosition) {
 780             m_win->SetScrollPos( wxHORIZONTAL, m_xScrollPosition );
 781             m_targetWindow->ScrollWindow( (old_x-m_xScrollPosition)*m_xScrollPixelsPerLine, 0,
 782                                           GetRect() );
 783         }
 784     }
 785     if ((y_pos != -1) && (m_yScrollPixelsPerLine))
 786     {
 787         int old_y = m_yScrollPosition;
 788         m_yScrollPosition = y_pos;
 789
 790         // Calculate page size i.e. number of scroll units you get on the
 791         // current client window
 792         int noPagePositions = (int) ( (h/(double)m_yScrollPixelsPerLine) + 0.5 );
 793         if (noPagePositions < 1) noPagePositions = 1;
 794
 795         // Correct position if greater than extent of canvas minus
 796         // the visible portion of it or if below zero
 797         m_yScrollPosition = wxMin( m_yScrollLines-noPagePositions, m_yScrollPosition );
 798         m_yScrollPosition = wxMax( 0, m_yScrollPosition );
 799
 800         if (old_y != m_yScrollPosition) {
 801             m_win->SetScrollPos( wxVERTICAL, m_yScrollPosition );
 802             m_targetWindow->ScrollWindow( 0, (old_y-m_yScrollPosition)*m_yScrollPixelsPerLine,
 803                                           GetRect() );
 804         }
 805     }
 806
 807 #ifdef __WXMAC__
 808     m_targetWindow->MacUpdateImmediately();
 809 #endif
 810
 811 }
 812
 813 void wxScrollHelper::EnableScrolling (bool x_scroll, bool y_scroll)
 814 {
 815     m_xScrollingEnabled = x_scroll;
 816     m_yScrollingEnabled = y_scroll;
 817 }
 818
 819 void wxScrollHelper::GetVirtualSize (int *x, int *y) const
 820 {
 821     if ( x )
 822         *x = m_xScrollPixelsPerLine * m_xScrollLines;
 823     if ( y )
 824         *y = m_yScrollPixelsPerLine * m_yScrollLines;
 825 }
 826
 827 // Where the current view starts from
 828 void wxScrollHelper::GetViewStart (int *x, int *y) const
 829 {
 830     if ( x )
 831         *x = m_xScrollPosition;
 832     if ( y )
 833         *y = m_yScrollPosition;
 834 }
 835
 836 void wxScrollHelper::CalcScrolledPosition(int x, int y, int *xx, int *yy) const
 837 {
 838     if ( xx )
 839         *xx = x - m_xScrollPosition * m_xScrollPixelsPerLine;
 840     if ( yy )
 841         *yy = y - m_yScrollPosition * m_yScrollPixelsPerLine;
 842 }
 843
 844 void wxScrollHelper::CalcUnscrolledPosition(int x, int y, int *xx, int *yy) const
 845 {
 846     if ( xx )
 847         *xx = x + m_xScrollPosition * m_xScrollPixelsPerLine;
 848     if ( yy )
 849         *yy = y + m_yScrollPosition * m_yScrollPixelsPerLine;
 850 }
 851
 852 // ----------------------------------------------------------------------------
 853 // event handlers
 854 // ----------------------------------------------------------------------------
 855
 856 // Default OnSize resets scrollbars, if any
 857 void wxScrollHelper::HandleOnSize(wxSizeEvent& WXUNUSED(event))
 858 {
 859 #if wxUSE_CONSTRAINTS
 860     if ( m_win->GetAutoLayout() )
 861         m_win->Layout();
 862 #endif
 863
 864     AdjustScrollbars();
 865 }
 866
 867 // This calls OnDraw, having adjusted the origin according to the current
 868 // scroll position
 869 void wxScrollHelper::HandleOnPaint(wxPaintEvent& WXUNUSED(event))
 870 {
 871     // don't use m_targetWindow here, this is always called for ourselves
 872     wxPaintDC dc(m_win);
 873     DoPrepareDC(dc);
 874
 875     OnDraw(dc);
 876 }
 877
 878 // kbd handling: notice that we use OnChar() and not OnKeyDown() for
 879 // compatibility here - if we used OnKeyDown(), the programs which process
 880 // arrows themselves in their OnChar() would never get the message and like
 881 // this they always have the priority
 882 void wxScrollHelper::HandleOnChar(wxKeyEvent& event)
 883 {
 884     int stx, sty,       // view origin
 885         szx, szy,       // view size (total)
 886         clix, cliy;     // view size (on screen)
 887
 888     GetViewStart(&stx, &sty);
 889     GetTargetSize(&clix, &cliy);
 890     GetVirtualSize(&szx, &szy);
 891
 892     if( m_xScrollPixelsPerLine )
 893     {
 894         clix /= m_xScrollPixelsPerLine;
 895         szx /= m_xScrollPixelsPerLine;
 896     }
 897     else
 898     {
 899         clix = 0;
 900         szx = -1;
 901     }
 902     if( m_yScrollPixelsPerLine )
 903     {
 904         cliy /= m_yScrollPixelsPerLine;
 905         szy /= m_yScrollPixelsPerLine;
 906     }
 907     else
 908     {
 909         cliy = 0;
 910         szy = -1;
 911     }
 912
 913     int xScrollOld = m_xScrollPosition,
 914         yScrollOld = m_yScrollPosition;
 915
 916     int dsty;
 917     switch ( event.KeyCode() )
 918     {
 919         case WXK_PAGEUP:
 920         case WXK_PRIOR:
 921             dsty = sty - (5 * cliy / 6);
 922             Scroll(-1, (dsty == -1) ? 0 : dsty);
 923             break;
 924
 925         case WXK_PAGEDOWN:
 926         case WXK_NEXT:
 927             Scroll(-1, sty + (5 * cliy / 6));
 928             break;
 929
 930         case WXK_HOME:
 931             Scroll(0, event.ControlDown() ? 0 : -1);
 932             break;
 933
 934         case WXK_END:
 935             Scroll(szx - clix, event.ControlDown() ? szy - cliy : -1);
 936             break;
 937
 938         case WXK_UP:
 939             Scroll(-1, sty - 1);
 940             break;
 941
 942         case WXK_DOWN:
 943             Scroll(-1, sty + 1);
 944             break;
 945
 946         case WXK_LEFT:
 947             Scroll(stx - 1, -1);
 948             break;
 949
 950         case WXK_RIGHT:
 951             Scroll(stx + 1, -1);
 952             break;
 953
 954         default:
 955             // not for us
 956             event.Skip();
 957     }
 958
 959     if ( m_xScrollPosition != xScrollOld )
 960     {
 961         wxScrollWinEvent event(wxEVT_SCROLLWIN_THUMBTRACK, m_xScrollPosition,
 962                                wxHORIZONTAL);
 963         event.SetEventObject(m_win);
 964         m_win->GetEventHandler()->ProcessEvent(event);
 965     }
 966
 967     if ( m_yScrollPosition != yScrollOld )
 968     {
 969         wxScrollWinEvent event(wxEVT_SCROLLWIN_THUMBTRACK, m_yScrollPosition,
 970                                wxVERTICAL);
 971         event.SetEventObject(m_win);
 972         m_win->GetEventHandler()->ProcessEvent(event);
 973     }
 974 }
 975
 976 // ----------------------------------------------------------------------------
 977 // autoscroll stuff: these functions deal with sending fake scroll events when
 978 // a captured mouse is being held outside the window
 979 // ----------------------------------------------------------------------------
 980
 981 bool wxScrollHelper::SendAutoScrollEvents(wxScrollWinEvent& event) const
 982 {
 983     // only send the event if the window is scrollable in this direction
 984     wxWindow *win = (wxWindow *)event.GetEventObject();
 985     return win->HasScrollbar(event.GetOrientation());
 986 }
 987
 988 void wxScrollHelper::StopAutoScrolling()
 989 {
 990     if ( m_timerAutoScroll )
 991     {
 992         delete m_timerAutoScroll;
 993         m_timerAutoScroll = (wxTimer *)NULL;
 994     }
 995 }
 996
 997 void wxScrollHelper::HandleOnMouseEnter(wxMouseEvent& event)
 998 {
 999     StopAutoScrolling();
1000
1001     event.Skip();
1002 }
1003
1004 void wxScrollHelper::HandleOnMouseLeave(wxMouseEvent& event)
1005 {
1006     // don't prevent the usual processing of the event from taking place
1007     event.Skip();
1008
1009     // when a captured mouse leave a scrolled window we start generate
1010     // scrolling events to allow, for example, extending selection beyond the
1011     // visible area in some controls
1012     if ( wxWindow::GetCapture() == m_targetWindow )
1013     {
1014         // where is the mouse leaving?
1015         int pos, orient;
1016         wxPoint pt = event.GetPosition();
1017         if ( pt.x < 0 )
1018         {
1019             orient = wxHORIZONTAL;
1020             pos = 0;
1021         }
1022         else if ( pt.y < 0 )
1023         {
1024             orient = wxVERTICAL;
1025             pos = 0;
1026         }
1027         else // we're lower or to the right of the window
1028         {
1029             wxSize size = m_targetWindow->GetClientSize();
1030             if ( pt.x > size.x )
1031             {
1032                 orient = wxHORIZONTAL;
1033                 pos = m_xScrollLines;
1034             }
1035             else if ( pt.y > size.y )
1036             {
1037                 orient = wxVERTICAL;
1038                 pos = m_yScrollLines;
1039             }
1040             else // this should be impossible
1041             {
1042                 // but seems to happen sometimes under wxMSW - maybe it's a bug
1043                 // there but for now just ignore it
1044
1045                 //wxFAIL_MSG( _T("can't understand where has mouse gone") );
1046
1047                 return;
1048             }
1049         }
1050
1051         // only start the auto scroll timer if the window can be scrolled in
1052         // this direction
1053         if ( !m_targetWindow->HasScrollbar(orient) )
1054             return;
1055
1056         delete m_timerAutoScroll;
1057         m_timerAutoScroll = new wxAutoScrollTimer
1058                                 (
1059                                     m_targetWindow, this,
1060                                     pos == 0 ? wxEVT_SCROLLWIN_LINEUP
1061                                              : wxEVT_SCROLLWIN_LINEDOWN,
1062                                     pos,
1063                                     orient
1064                                 );
1065         m_timerAutoScroll->Start(50); // FIXME: make configurable
1066     }
1067 }
1068
1069 #if wxUSE_MOUSEWHEEL
1070
1071 void wxScrollHelper::HandleOnMouseWheel(wxMouseEvent& event)
1072 {
1073     m_wheelRotation += event.GetWheelRotation();
1074     int lines = m_wheelRotation / event.GetWheelDelta();
1075     m_wheelRotation -= lines * event.GetWheelDelta();
1076
1077     if (lines != 0)
1078     {
1079         lines *= event.GetLinesPerAction();
1080
1081         wxScrollWinEvent newEvent;
1082
1083         newEvent.SetPosition(0);
1084         newEvent.SetOrientation(wxVERTICAL);
1085         newEvent.m_eventObject = m_win;
1086         if (lines > 0)
1087             newEvent.m_eventType = wxEVT_SCROLLWIN_LINEUP;
1088         else
1089             newEvent.m_eventType = wxEVT_SCROLLWIN_LINEDOWN;
1090
1091         int times = abs(lines);
1092         for (; times > 0; times --)
1093             m_win->GetEventHandler()->ProcessEvent(newEvent);
1094
1095         /* Old Way */
1096         // int vsx, vsy;
1097         // GetViewStart(&vsx, &vsy);
1098         // Scroll(-1, vsy - lines);
1099     }
1100 }
1101
1102 #endif // wxUSE_MOUSEWHEEL
1103
1104 // ----------------------------------------------------------------------------
1105 // wxGenericScrolledWindow implementation
1106 // ----------------------------------------------------------------------------
1107
1108 IMPLEMENT_DYNAMIC_CLASS(wxGenericScrolledWindow, wxPanel)
1109
1110 BEGIN_EVENT_TABLE(wxGenericScrolledWindow, wxPanel)
1111     EVT_PAINT(wxGenericScrolledWindow::OnPaint)
1112 END_EVENT_TABLE()
1113
1114 bool wxGenericScrolledWindow::Create(wxWindow *parent,
1115                               wxWindowID id,
1116                               const wxPoint& pos,
1117                               const wxSize& size,
1118                               long style,
1119                               const wxString& name)
1120 {
1121     m_targetWindow = this;
1122
1123     bool ok = wxPanel::Create(parent, id, pos, size, style, name);
1124
1125 #ifdef __WXMSW__
1126     // we need to process arrows ourselves for scrolling
1127     m_lDlgCode |= DLGC_WANTARROWS;
1128 #endif // __WXMSW__
1129
1130     return ok;
1131 }
1132
1133 wxGenericScrolledWindow::~wxGenericScrolledWindow()
1134 {
1135 }
1136
1137 void wxGenericScrolledWindow::OnPaint(wxPaintEvent& event)
1138 {
1139     // the user code didn't really draw the window if we got here, so set this
1140     // flag to try to call OnDraw() later
1141     m_handler->ResetDrawnFlag();
1142
1143     event.Skip();
1144 }
1145
1146 #if WXWIN_COMPATIBILITY
1147
1148 void wxGenericScrolledWindow::GetScrollUnitsPerPage (int *x_page, int *y_page) const
1149 {
1150       *x_page = GetScrollPageSize(wxHORIZONTAL);
1151       *y_page = GetScrollPageSize(wxVERTICAL);
1152 }
1153
1154 void wxGenericScrolledWindow::CalcUnscrolledPosition(int x, int y, float *xx, float *yy) const
1155 {
1156     if ( xx )
1157         *xx = (float)(x + m_xScrollPosition * m_xScrollPixelsPerLine);
1158     if ( yy )
1159         *yy = (float)(y + m_yScrollPosition * m_yScrollPixelsPerLine);
1160 }
1161
1162 #endif // WXWIN_COMPATIBILITY
1163
1164 #endif // !wxGTK
1165