src/generic/splitter.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/generic/splitter.cpp
   3 // Purpose:     wxSplitterWindow implementation
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     01/02/97
   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 "splitter.h"
  14 #endif
  15
  16 // For compilers that support precompilation, includes "wx.h".
  17 #include "wx/wxprec.h"
  18
  19 #if wxUSE_SPLITTER
  20
  21 #ifdef __BORLANDC__
  22     #pragma hdrstop
  23 #endif
  24
  25 #ifndef WX_PRECOMP
  26     #include "wx/string.h"
  27     #include "wx/utils.h"
  28     #include "wx/log.h"
  29
  30     #include "wx/dcscreen.h"
  31
  32     #include "wx/window.h"
  33     #include "wx/dialog.h"
  34     #include "wx/frame.h"
  35
  36     #include "wx/settings.h"
  37 #endif
  38
  39 #include "wx/renderer.h"
  40
  41 #include "wx/splitter.h"
  42
  43 #include <stdlib.h>
  44
  45 DEFINE_EVENT_TYPE(wxEVT_COMMAND_SPLITTER_SASH_POS_CHANGED)
  46 DEFINE_EVENT_TYPE(wxEVT_COMMAND_SPLITTER_SASH_POS_CHANGING)
  47 DEFINE_EVENT_TYPE(wxEVT_COMMAND_SPLITTER_DOUBLECLICKED)
  48 DEFINE_EVENT_TYPE(wxEVT_COMMAND_SPLITTER_UNSPLIT)
  49
  50 IMPLEMENT_DYNAMIC_CLASS(wxSplitterWindow, wxWindow)
  51
  52 /*
  53     TODO PROPERTIES
  54         style wxSP_3D
  55         sashpos (long , 0 )
  56         minsize (long -1 )
  57         object, object_ref
  58         orientation
  59 */
  60
  61 IMPLEMENT_DYNAMIC_CLASS(wxSplitterEvent, wxNotifyEvent)
  62
  63 BEGIN_EVENT_TABLE(wxSplitterWindow, wxWindow)
  64     EVT_PAINT(wxSplitterWindow::OnPaint)
  65     EVT_SIZE(wxSplitterWindow::OnSize)
  66     EVT_MOUSE_EVENTS(wxSplitterWindow::OnMouseEvent)
  67
  68 #if defined( __WXMSW__ ) || defined( __WXMAC__)
  69     EVT_SET_CURSOR(wxSplitterWindow::OnSetCursor)
  70 #endif // wxMSW
  71
  72     WX_EVENT_TABLE_CONTROL_CONTAINER(wxSplitterWindow)
  73 END_EVENT_TABLE()
  74
  75 WX_DELEGATE_TO_CONTROL_CONTAINER(wxSplitterWindow);
  76
  77 bool wxSplitterWindow::Create(wxWindow *parent, wxWindowID id,
  78                                    const wxPoint& pos,
  79                                    const wxSize& size,
  80                                    long style,
  81                                    const wxString& name)
  82 {
  83     // allow TABbing from one window to the other
  84     style |= wxTAB_TRAVERSAL;
  85
  86     // we draw our border ourselves to blend the sash with it
  87     style &= ~wxBORDER_MASK;
  88     style |= wxBORDER_NONE;
  89
  90     if ( !wxWindow::Create(parent, id, pos, size, style, name) )
  91         return false;
  92
  93     m_permitUnsplitAlways = (style & wxSP_PERMIT_UNSPLIT) != 0;
  94
  95     return true;
  96 }
  97
  98 void wxSplitterWindow::Init()
  99 {
 100     m_container.SetContainerWindow(this);
 101
 102     m_splitMode = wxSPLIT_VERTICAL;
 103     m_permitUnsplitAlways = true;
 104     m_windowOne = (wxWindow *) NULL;
 105     m_windowTwo = (wxWindow *) NULL;
 106     m_dragMode = wxSPLIT_DRAG_NONE;
 107     m_oldX = 0;
 108     m_oldY = 0;
 109     m_firstX = 0;
 110     m_firstY = 0;
 111     m_sashPosition = m_requestedSashPosition = 0;
 112     m_checkRequestedSashPosition = false;
 113     m_minimumPaneSize = 0;
 114     m_sashCursorWE = wxCursor(wxCURSOR_SIZEWE);
 115     m_sashCursorNS = wxCursor(wxCURSOR_SIZENS);
 116     m_sashTrackerPen = new wxPen(*wxBLACK, 2, wxSOLID);
 117
 118     m_needUpdating = false;
 119     m_isHot = false;
 120 }
 121
 122 wxSplitterWindow::~wxSplitterWindow()
 123 {
 124     delete m_sashTrackerPen;
 125 }
 126
 127 // ----------------------------------------------------------------------------
 128 // entering/leaving sash
 129 // ----------------------------------------------------------------------------
 130
 131 void wxSplitterWindow::RedrawIfHotSensitive(bool isHot)
 132 {
 133     if ( wxRendererNative::Get().GetSplitterParams(this).isHotSensitive )
 134     {
 135         m_isHot = isHot;
 136
 137         wxClientDC dc(this);
 138         DrawSash(dc);
 139     }
 140     //else: we don't change our appearance, don't redraw to avoid flicker
 141 }
 142
 143 void wxSplitterWindow::OnEnterSash()
 144 {
 145     SetResizeCursor();
 146
 147     RedrawIfHotSensitive(true);
 148 }
 149
 150 void wxSplitterWindow::OnLeaveSash()
 151 {
 152     SetCursor(*wxSTANDARD_CURSOR);
 153
 154     RedrawIfHotSensitive(false);
 155 }
 156
 157 void wxSplitterWindow::SetResizeCursor()
 158 {
 159     SetCursor(m_splitMode == wxSPLIT_VERTICAL ? m_sashCursorWE
 160                                               : m_sashCursorNS);
 161 }
 162
 163 // ----------------------------------------------------------------------------
 164 // other event handlers
 165 // ----------------------------------------------------------------------------
 166
 167 void wxSplitterWindow::OnPaint(wxPaintEvent& WXUNUSED(event))
 168 {
 169     wxPaintDC dc(this);
 170
 171     DrawSash(dc);
 172 }
 173
 174 void wxSplitterWindow::OnInternalIdle()
 175 {
 176     wxWindow::OnInternalIdle();
 177
 178     // if this is the first idle time after a sash position has potentially
 179     // been set, allow SizeWindows to check for a requested size.
 180     if (!m_checkRequestedSashPosition)
 181     {
 182         m_checkRequestedSashPosition = true;
 183         SizeWindows();
 184         return; // it won't needUpdating in this case
 185     }
 186
 187     if (m_needUpdating)
 188         SizeWindows();
 189 }
 190
 191 void wxSplitterWindow::OnMouseEvent(wxMouseEvent& event)
 192 {
 193     int x = (int)event.GetX(),
 194         y = (int)event.GetY();
 195
 196     if (GetWindowStyle() & wxSP_NOSASH)
 197         return;
 198
 199     // with wxSP_LIVE_UPDATE style the splitter windows are always resized
 200     // following the mouse movement while it drags the sash, without it we only
 201     // draw the sash at the new position but only resize the windows when the
 202     // dragging is finished
 203 #if defined( __WXMAC__ ) && TARGET_API_MAC_OSX == 1
 204     bool isLive = true ;
 205 #else
 206     bool isLive = (GetWindowStyleFlag() & wxSP_LIVE_UPDATE) != 0;
 207 #endif
 208     if (event.LeftDown())
 209     {
 210         if ( SashHitTest(x, y) )
 211         {
 212             // Start the drag now
 213             m_dragMode = wxSPLIT_DRAG_DRAGGING;
 214
 215             // Capture mouse and set the cursor
 216             CaptureMouse();
 217             SetResizeCursor();
 218
 219             if ( !isLive )
 220             {
 221                 // remember the initial sash position and draw the initial
 222                 // shadow sash
 223                 m_sashPositionCurrent = m_sashPosition;
 224
 225                 DrawSashTracker(x, y);
 226             }
 227
 228             m_oldX = x;
 229             m_oldY = y;
 230
 231             SetResizeCursor();
 232             return;
 233         }
 234     }
 235     else if (event.LeftUp() && m_dragMode == wxSPLIT_DRAG_DRAGGING)
 236     {
 237         // We can stop dragging now and see what we've got.
 238         m_dragMode = wxSPLIT_DRAG_NONE;
 239
 240         // Release mouse and unset the cursor
 241         ReleaseMouse();
 242         SetCursor(* wxSTANDARD_CURSOR);
 243
 244         // exit if unsplit after doubleclick
 245         if ( !IsSplit() )
 246         {
 247             return;
 248         }
 249
 250         // Erase old tracker
 251         if ( !isLive )
 252         {
 253             DrawSashTracker(m_oldX, m_oldY);
 254         }
 255
 256         // the position of the click doesn't exactly correspond to
 257         // m_sashPosition, rather it changes it by the distance by which the
 258         // mouse has moved
 259         int diff = m_splitMode == wxSPLIT_VERTICAL ? x - m_oldX : y - m_oldY;
 260
 261         int posSashOld = isLive ? m_sashPosition : m_sashPositionCurrent;
 262         int posSashNew = OnSashPositionChanging(posSashOld + diff);
 263         if ( posSashNew == -1 )
 264         {
 265             // change not allowed
 266             return;
 267         }
 268
 269         if ( m_permitUnsplitAlways || m_minimumPaneSize == 0 )
 270         {
 271             // Deal with possible unsplit scenarios
 272             if ( posSashNew == 0 )
 273             {
 274                 // We remove the first window from the view
 275                 wxWindow *removedWindow = m_windowOne;
 276                 m_windowOne = m_windowTwo;
 277                 m_windowTwo = (wxWindow *) NULL;
 278                 OnUnsplit(removedWindow);
 279                 wxSplitterEvent event(wxEVT_COMMAND_SPLITTER_UNSPLIT, this);
 280                 event.m_data.win = removedWindow;
 281                 (void)DoSendEvent(event);
 282                 SetSashPositionAndNotify(0);
 283             }
 284             else if ( posSashNew == GetWindowSize() )
 285             {
 286                 // We remove the second window from the view
 287                 wxWindow *removedWindow = m_windowTwo;
 288                 m_windowTwo = (wxWindow *) NULL;
 289                 OnUnsplit(removedWindow);
 290                 wxSplitterEvent event(wxEVT_COMMAND_SPLITTER_UNSPLIT, this);
 291                 event.m_data.win = removedWindow;
 292                 (void)DoSendEvent(event);
 293                 SetSashPositionAndNotify(0);
 294             }
 295             else
 296             {
 297                 SetSashPositionAndNotify(posSashNew);
 298             }
 299         }
 300         else
 301         {
 302             SetSashPositionAndNotify(posSashNew);
 303         }
 304
 305         SizeWindows();
 306     }  // left up && dragging
 307     else if ((event.Moving() || event.Leaving() || event.Entering()) && (m_dragMode == wxSPLIT_DRAG_NONE))
 308     {
 309         if ( event.Leaving() || !SashHitTest(x, y) )
 310             OnLeaveSash();
 311         else
 312             OnEnterSash();
 313     }
 314     else if (event.Dragging() && (m_dragMode == wxSPLIT_DRAG_DRAGGING))
 315     {
 316         int diff = m_splitMode == wxSPLIT_VERTICAL ? x - m_oldX : y - m_oldY;
 317         if ( !diff )
 318         {
 319             // nothing to do, mouse didn't really move far enough
 320             return;
 321         }
 322
 323         int posSashOld = isLive ? m_sashPosition : m_sashPositionCurrent;
 324         int posSashNew = OnSashPositionChanging(posSashOld + diff);
 325         if ( posSashNew == -1 )
 326         {
 327             // change not allowed
 328             return;
 329         }
 330
 331         if ( posSashNew == m_sashPosition )
 332             return;
 333
 334         // Erase old tracker
 335         if ( !isLive )
 336         {
 337             DrawSashTracker(m_oldX, m_oldY);
 338         }
 339
 340         if (m_splitMode == wxSPLIT_VERTICAL)
 341             x = posSashNew;
 342         else
 343             y = posSashNew;
 344
 345         // Remember old positions
 346         m_oldX = x;
 347         m_oldY = y;
 348
 349 #ifdef __WXMSW__
 350         // As we captured the mouse, we may get the mouse events from outside
 351         // our window - for example, negative values in x, y. This has a weird
 352         // consequence under MSW where we use unsigned values sometimes and
 353         // signed ones other times: the coordinates turn as big positive
 354         // numbers and so the sash is drawn on the *right* side of the window
 355         // instead of the left (or bottom instead of top). Correct this.
 356         if ( (short)m_oldX < 0 )
 357             m_oldX = 0;
 358         if ( (short)m_oldY < 0 )
 359             m_oldY = 0;
 360 #endif // __WXMSW__
 361
 362         // Draw new one
 363         if ( !isLive )
 364         {
 365             m_sashPositionCurrent = posSashNew;
 366
 367             DrawSashTracker(m_oldX, m_oldY);
 368         }
 369         else
 370         {
 371             SetSashPositionAndNotify(posSashNew);
 372             m_needUpdating = true;
 373         }
 374     }
 375     else if ( event.LeftDClick() && m_windowTwo )
 376     {
 377         OnDoubleClickSash(x, y);
 378     }
 379 }
 380
 381 void wxSplitterWindow::OnSize(wxSizeEvent& event)
 382 {
 383     // only process this message if we're not iconized - otherwise iconizing
 384     // and restoring a window containing the splitter has a funny side effect
 385     // of changing the splitter position!
 386     wxWindow *parent = wxGetTopLevelParent(this);
 387     bool iconized;
 388
 389     wxTopLevelWindow *winTop = wxDynamicCast(parent, wxTopLevelWindow);
 390     if ( winTop )
 391     {
 392         iconized = winTop->IsIconized();
 393     }
 394     else
 395     {
 396         wxFAIL_MSG(wxT("should have a top level parent!"));
 397
 398         iconized = false;
 399     }
 400
 401     if ( iconized )
 402     {
 403         event.Skip();
 404
 405         return;
 406     }
 407
 408     if ( m_windowTwo )
 409     {
 410         int w, h;
 411         GetClientSize(&w, &h);
 412
 413         int size = m_splitMode == wxSPLIT_VERTICAL ? w : h;
 414         if ( m_sashPosition >= size - 5 )
 415             SetSashPositionAndNotify(wxMax(10, size - 40));
 416     }
 417
 418     SizeWindows();
 419 }
 420
 421 bool wxSplitterWindow::SashHitTest(int x, int y, int tolerance)
 422 {
 423     if ( m_windowTwo == NULL || m_sashPosition == 0)
 424         return false; // No sash
 425
 426     int z = m_splitMode == wxSPLIT_VERTICAL ? x : y;
 427     int hitMin = m_sashPosition - tolerance;
 428     int hitMax = m_sashPosition + GetSashSize() + tolerance;
 429
 430     return z >=  hitMin && z <= hitMax;
 431 }
 432
 433 int wxSplitterWindow::GetSashSize() const
 434 {
 435     return wxRendererNative::Get().GetSplitterParams(this).widthSash;
 436 }
 437
 438 int wxSplitterWindow::GetBorderSize() const
 439 {
 440     return wxRendererNative::Get().GetSplitterParams(this).border;
 441 }
 442
 443 // Draw the sash
 444 void wxSplitterWindow::DrawSash(wxDC& dc)
 445 {
 446     if (HasFlag(wxSP_3DBORDER))
 447         wxRendererNative::Get().DrawSplitterBorder
 448                             (
 449                                 this,
 450                                 dc,
 451                                 GetClientRect()
 452                             );
 453
 454     // don't draw sash if we're not split
 455     if ( m_sashPosition == 0 || !m_windowTwo )
 456         return;
 457
 458     // nor if we're configured to not show it
 459     if ( HasFlag(wxSP_NOSASH) )
 460         return;
 461
 462     wxRendererNative::Get().DrawSplitterSash
 463                             (
 464                                 this,
 465                                 dc,
 466                                 GetClientSize(),
 467                                 m_sashPosition,
 468                                 m_splitMode == wxSPLIT_VERTICAL ? wxVERTICAL
 469                                                                 : wxHORIZONTAL,
 470                                 m_isHot ? wxCONTROL_CURRENT : 0
 471                             );
 472 }
 473
 474 // Draw the sash tracker (for whilst moving the sash)
 475 void wxSplitterWindow::DrawSashTracker(int x, int y)
 476 {
 477     int w, h;
 478     GetClientSize(&w, &h);
 479
 480     wxScreenDC screenDC;
 481     int x1, y1;
 482     int x2, y2;
 483
 484     if ( m_splitMode == wxSPLIT_VERTICAL )
 485     {
 486         x1 = x; y1 = 2;
 487         x2 = x; y2 = h-2;
 488
 489         if ( x1 > w )
 490         {
 491             x1 = w; x2 = w;
 492         }
 493         else if ( x1 < 0 )
 494         {
 495             x1 = 0; x2 = 0;
 496         }
 497     }
 498     else
 499     {
 500         x1 = 2; y1 = y;
 501         x2 = w-2; y2 = y;
 502
 503         if ( y1 > h )
 504         {
 505             y1 = h;
 506             y2 = h;
 507         }
 508         else if ( y1 < 0 )
 509         {
 510             y1 = 0;
 511             y2 = 0;
 512         }
 513     }
 514
 515     ClientToScreen(&x1, &y1);
 516     ClientToScreen(&x2, &y2);
 517
 518     screenDC.SetLogicalFunction(wxINVERT);
 519     screenDC.SetPen(*m_sashTrackerPen);
 520     screenDC.SetBrush(*wxTRANSPARENT_BRUSH);
 521
 522     screenDC.DrawLine(x1, y1, x2, y2);
 523
 524     screenDC.SetLogicalFunction(wxCOPY);
 525 }
 526
 527 int wxSplitterWindow::GetWindowSize() const
 528 {
 529     wxSize size = GetClientSize();
 530
 531     return m_splitMode == wxSPLIT_VERTICAL ? size.x : size.y;
 532 }
 533
 534 int wxSplitterWindow::AdjustSashPosition(int sashPos) const
 535 {
 536     int window_size = GetWindowSize();
 537
 538     wxWindow *win;
 539
 540     win = GetWindow1();
 541     if ( win )
 542     {
 543         // the window shouldn't be smaller than its own minimal size nor
 544         // smaller than the minimual pane size specified for this splitter
 545         int minSize = m_splitMode == wxSPLIT_VERTICAL ? win->GetMinWidth()
 546                                                       : win->GetMinHeight();
 547
 548         if ( minSize == -1 || m_minimumPaneSize > minSize )
 549             minSize = m_minimumPaneSize;
 550
 551         minSize += GetBorderSize();
 552
 553         if ( sashPos < minSize )
 554             sashPos = minSize;
 555     }
 556
 557     win = GetWindow2();
 558     if ( win )
 559     {
 560         int minSize = m_splitMode == wxSPLIT_VERTICAL ? win->GetMinWidth()
 561                                                       : win->GetMinHeight();
 562
 563         if ( minSize == -1 || m_minimumPaneSize > minSize )
 564             minSize = m_minimumPaneSize;
 565
 566         int maxSize = window_size - minSize - GetBorderSize();
 567         if ( sashPos > maxSize )
 568             sashPos = maxSize;
 569     }
 570
 571     return sashPos;
 572 }
 573
 574 bool wxSplitterWindow::DoSetSashPosition(int sashPos)
 575 {
 576     int newSashPosition = AdjustSashPosition(sashPos);
 577
 578     if ( newSashPosition == m_sashPosition )
 579         return false;
 580
 581     m_sashPosition = newSashPosition;
 582
 583     return true;
 584 }
 585
 586 void wxSplitterWindow::SetSashPositionAndNotify(int sashPos)
 587 {
 588     // we must reset the request here, otherwise the sash would be stuck at
 589     // old position if the user attempted to move the sash after invalid
 590     // (e.g. smaller than minsize) sash position was requested using
 591     // SetSashPosition():
 592     m_requestedSashPosition = INT_MAX;
 593
 594     if ( DoSetSashPosition(sashPos) )
 595     {
 596         wxSplitterEvent event(wxEVT_COMMAND_SPLITTER_SASH_POS_CHANGED, this);
 597         event.m_data.pos = m_sashPosition;
 598
 599         (void)DoSendEvent(event);
 600     }
 601 }
 602
 603 // Position and size subwindows.
 604 // Note that the border size applies to each subwindow, not
 605 // including the edges next to the sash.
 606 void wxSplitterWindow::SizeWindows()
 607 {
 608     // check if we have delayed setting the real sash position
 609     if ( m_checkRequestedSashPosition && m_requestedSashPosition != INT_MAX )
 610     {
 611         int newSashPosition = ConvertSashPosition(m_requestedSashPosition);
 612         if ( newSashPosition != m_sashPosition )
 613         {
 614             DoSetSashPosition(newSashPosition);
 615         }
 616
 617         if ( newSashPosition <= m_sashPosition
 618             && newSashPosition >= m_sashPosition - GetBorderSize() )
 619         {
 620             // don't update it any more
 621             m_requestedSashPosition = INT_MAX;
 622         }
 623     }
 624
 625     int w, h;
 626     GetClientSize(&w, &h);
 627
 628     if ( GetWindow1() && !GetWindow2() )
 629     {
 630         GetWindow1()->SetSize(GetBorderSize(), GetBorderSize(),
 631                               w - 2*GetBorderSize(), h - 2*GetBorderSize());
 632     }
 633     else if ( GetWindow1() && GetWindow2() )
 634     {
 635         const int border = GetBorderSize(),
 636                   sash = GetSashSize();
 637
 638         int size1 = GetSashPosition() - border,
 639             size2 = GetSashPosition() + sash;
 640
 641         int x2, y2, w1, h1, w2, h2;
 642         if ( GetSplitMode() == wxSPLIT_VERTICAL )
 643         {
 644             w1 = size1;
 645             w2 = w - 2*border - sash - w1;
 646             h1 =
 647             h2 = h - 2*border;
 648             x2 = size2;
 649             y2 = border;
 650         }
 651         else // horz splitter
 652         {
 653             w1 =
 654             w2 = w - 2*border;
 655             h1 = size1;
 656             h2 = h - 2*border - sash - h1;
 657             x2 = border;
 658             y2 = size2;
 659         }
 660
 661         GetWindow1()->SetSize(border, border, w1, h1);
 662         GetWindow2()->SetSize(x2, y2, w2, h2);
 663     }
 664
 665     wxClientDC dc(this);
 666     DrawSash(dc);
 667
 668     SetNeedUpdating(false);
 669 }
 670
 671 // Set pane for unsplit window
 672 void wxSplitterWindow::Initialize(wxWindow *window)
 673 {
 674     wxASSERT_MSG( (!window || (window && window->GetParent() == this)),
 675                   _T("windows in the splitter should have it as parent!") );
 676
 677     m_windowOne = window;
 678     m_windowTwo = (wxWindow *) NULL;
 679     DoSetSashPosition(0);
 680 }
 681
 682 // Associates the given window with window 2, drawing the appropriate sash
 683 // and changing the split mode.
 684 // Does nothing and returns false if the window is already split.
 685 bool wxSplitterWindow::DoSplit(wxSplitMode mode,
 686                                wxWindow *window1, wxWindow *window2,
 687                                int sashPosition)
 688 {
 689     if ( IsSplit() )
 690         return false;
 691
 692     wxCHECK_MSG( window1 && window2, false,
 693                  _T("can not split with NULL window(s)") );
 694
 695     wxCHECK_MSG( window1->GetParent() == this && window2->GetParent() == this, false,
 696                   _T("windows in the splitter should have it as parent!") );
 697
 698     m_splitMode = mode;
 699     m_windowOne = window1;
 700     m_windowTwo = window2;
 701
 702     // remember the sash position we want to set for later if we can't set it
 703     // right now (e.g. because the window is too small)
 704     m_requestedSashPosition = sashPosition;
 705     m_checkRequestedSashPosition = false;
 706
 707     DoSetSashPosition(ConvertSashPosition(sashPosition));
 708
 709     SizeWindows();
 710
 711     return true;
 712 }
 713
 714 int wxSplitterWindow::ConvertSashPosition(int sashPosition) const
 715 {
 716     if ( sashPosition > 0 )
 717     {
 718         return sashPosition;
 719     }
 720     else if ( sashPosition < 0 )
 721     {
 722         // It's negative so adding is subtracting
 723         return GetWindowSize() + sashPosition;
 724     }
 725     else // sashPosition == 0
 726     {
 727         // default, put it in the centre
 728         return GetWindowSize() / 2;
 729     }
 730 }
 731
 732 // Remove the specified (or second) window from the view
 733 // Doesn't actually delete the window.
 734 bool wxSplitterWindow::Unsplit(wxWindow *toRemove)
 735 {
 736     if ( ! IsSplit() )
 737         return false;
 738
 739     wxWindow *win;
 740     if ( toRemove == NULL || toRemove == m_windowTwo)
 741     {
 742         win = m_windowTwo ;
 743         m_windowTwo = (wxWindow *) NULL;
 744     }
 745     else if ( toRemove == m_windowOne )
 746     {
 747         win = m_windowOne ;
 748         m_windowOne = m_windowTwo;
 749         m_windowTwo = (wxWindow *) NULL;
 750     }
 751     else
 752     {
 753         wxFAIL_MSG(wxT("splitter: attempt to remove a non-existent window"));
 754
 755         return false;
 756     }
 757
 758     OnUnsplit(win);
 759     DoSetSashPosition(0);
 760     SizeWindows();
 761
 762     return true;
 763 }
 764
 765 // Replace a window with another one
 766 bool wxSplitterWindow::ReplaceWindow(wxWindow *winOld, wxWindow *winNew)
 767 {
 768     wxCHECK_MSG( winOld, false, wxT("use one of Split() functions instead") );
 769     wxCHECK_MSG( winNew, false, wxT("use Unsplit() functions instead") );
 770
 771     if ( winOld == m_windowTwo )
 772     {
 773         m_windowTwo = winNew;
 774     }
 775     else if ( winOld == m_windowOne )
 776     {
 777         m_windowOne = winNew;
 778     }
 779     else
 780     {
 781         wxFAIL_MSG(wxT("splitter: attempt to replace a non-existent window"));
 782
 783         return false;
 784     }
 785
 786     SizeWindows();
 787
 788     return true;
 789 }
 790
 791 void wxSplitterWindow::SetMinimumPaneSize(int min)
 792 {
 793     m_minimumPaneSize = min;
 794     int pos = m_requestedSashPosition != INT_MAX ? m_requestedSashPosition : m_sashPosition;
 795     SetSashPosition(pos); // re-check limits
 796 }
 797
 798 void wxSplitterWindow::SetSashPosition(int position, bool redraw)
 799 {
 800     // remember the sash position we want to set for later if we can't set it
 801     // right now (e.g. because the window is too small)
 802     m_requestedSashPosition = position;
 803     m_checkRequestedSashPosition = false;
 804
 805     DoSetSashPosition(ConvertSashPosition(position));
 806
 807     if ( redraw )
 808     {
 809         SizeWindows();
 810     }
 811 }
 812
 813 // Make sure the child window sizes are updated. This is useful
 814 // for reducing flicker by updating the sizes before a
 815 // window is shown, if you know the overall size is correct.
 816 void wxSplitterWindow::UpdateSize()
 817 {
 818     m_checkRequestedSashPosition = true;
 819     SizeWindows();
 820     m_checkRequestedSashPosition = false;
 821 }
 822
 823 bool wxSplitterWindow::DoSendEvent(wxSplitterEvent& event)
 824 {
 825     return !GetEventHandler()->ProcessEvent(event) || event.IsAllowed();
 826 }
 827
 828 // ---------------------------------------------------------------------------
 829 // wxSplitterWindow virtual functions: they now just generate the events
 830 // ---------------------------------------------------------------------------
 831
 832 bool wxSplitterWindow::OnSashPositionChange(int WXUNUSED(newSashPosition))
 833 {
 834     // always allow by default
 835     return true;
 836 }
 837
 838 int wxSplitterWindow::OnSashPositionChanging(int newSashPosition)
 839 {
 840     // If within UNSPLIT_THRESHOLD from edge, set to edge to cause closure.
 841     const int UNSPLIT_THRESHOLD = 4;
 842
 843     // first of all, check if OnSashPositionChange() doesn't forbid this change
 844     if ( !OnSashPositionChange(newSashPosition) )
 845     {
 846         // it does
 847         return -1;
 848     }
 849
 850     // Obtain relevant window dimension for bottom / right threshold check
 851     int window_size = GetWindowSize();
 852
 853     bool unsplit_scenario = false;
 854     if ( m_permitUnsplitAlways || m_minimumPaneSize == 0 )
 855     {
 856         // Do edge detection if unsplit premitted
 857         if ( newSashPosition <= UNSPLIT_THRESHOLD )
 858         {
 859             // threshold top / left check
 860             newSashPosition = 0;
 861             unsplit_scenario = true;
 862         }
 863         if ( newSashPosition >= window_size - UNSPLIT_THRESHOLD )
 864         {
 865             // threshold bottom/right check
 866             newSashPosition = window_size;
 867             unsplit_scenario = true;
 868         }
 869     }
 870
 871     if ( !unsplit_scenario )
 872     {
 873         // If resultant pane would be too small, enlarge it
 874         newSashPosition = AdjustSashPosition(newSashPosition);
 875     }
 876
 877     // If the result is out of bounds it means minimum size is too big,
 878     // so split window in half as best compromise.
 879     if ( newSashPosition < 0 || newSashPosition > window_size )
 880         newSashPosition = window_size / 2;
 881
 882     // now let the event handler have it
 883     //
 884     // FIXME: shouldn't we do it before the adjustments above so as to ensure
 885     //        that the sash position is always reasonable?
 886     wxSplitterEvent event(wxEVT_COMMAND_SPLITTER_SASH_POS_CHANGING, this);
 887     event.m_data.pos = newSashPosition;
 888
 889     if ( !DoSendEvent(event) )
 890     {
 891         // the event handler vetoed the change
 892         newSashPosition = -1;
 893     }
 894     else
 895     {
 896         // it could have been changed by it
 897         newSashPosition = event.GetSashPosition();
 898     }
 899
 900     return newSashPosition;
 901 }
 902
 903 // Called when the sash is double-clicked. The default behaviour is to remove
 904 // the sash if the minimum pane size is zero.
 905 void wxSplitterWindow::OnDoubleClickSash(int x, int y)
 906 {
 907     wxCHECK_RET(m_windowTwo, wxT("splitter: no window to remove"));
 908
 909     // new code should handle events instead of using the virtual functions
 910     wxSplitterEvent event(wxEVT_COMMAND_SPLITTER_DOUBLECLICKED, this);
 911     event.m_data.pt.x = x;
 912     event.m_data.pt.y = y;
 913     if ( DoSendEvent(event) )
 914     {
 915         if ( GetMinimumPaneSize() == 0 || m_permitUnsplitAlways )
 916         {
 917             wxWindow* win = m_windowTwo;
 918             if ( Unsplit(win) )
 919             {
 920                 wxSplitterEvent unsplitEvent(wxEVT_COMMAND_SPLITTER_UNSPLIT, this);
 921                 unsplitEvent.m_data.win = win;
 922                 (void)DoSendEvent(unsplitEvent);
 923             }
 924         }
 925     }
 926     //else: blocked by user
 927 }
 928
 929 void wxSplitterWindow::OnUnsplit(wxWindow *winRemoved)
 930 {
 931     // call this before calling the event handler which may delete the window
 932     winRemoved->Show(false);
 933 }
 934
 935 #if defined( __WXMSW__ ) || defined( __WXMAC__)
 936
 937 // this is currently called (and needed) under MSW only...
 938 void wxSplitterWindow::OnSetCursor(wxSetCursorEvent& event)
 939 {
 940     // if we don't do it, the resizing cursor might be set for child window:
 941     // and like this we explicitly say that our cursor should not be used for
 942     // children windows which overlap us
 943
 944     if ( SashHitTest(event.GetX(), event.GetY(), 0) )
 945     {
 946         // default processing is ok
 947         event.Skip();
 948     }
 949     //else: do nothing, in particular, don't call Skip()
 950 }
 951
 952 #endif // wxMSW || wxMac
 953
 954 #endif // wxUSE_SPLITTER
 955