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 #ifdef __WXMAC__
  40     #include "wx/mac/private.h"
  41 #endif
  42
  43 #include "wx/renderer.h"
  44
  45 #include "wx/splitter.h"
  46
  47 #include <stdlib.h>
  48
  49 DEFINE_EVENT_TYPE(wxEVT_COMMAND_SPLITTER_SASH_POS_CHANGED)
  50 DEFINE_EVENT_TYPE(wxEVT_COMMAND_SPLITTER_SASH_POS_CHANGING)
  51 DEFINE_EVENT_TYPE(wxEVT_COMMAND_SPLITTER_DOUBLECLICKED)
  52 DEFINE_EVENT_TYPE(wxEVT_COMMAND_SPLITTER_UNSPLIT)
  53
  54 IMPLEMENT_DYNAMIC_CLASS(wxSplitterWindow, wxWindow)
  55
  56 /*
  57     TODO PROPERTIES
  58         style wxSP_3D
  59         sashpos (long , 0 )
  60         minsize (long -1 )
  61         object, object_ref
  62         orientation
  63 */
  64
  65 IMPLEMENT_DYNAMIC_CLASS(wxSplitterEvent, wxNotifyEvent)
  66
  67 BEGIN_EVENT_TABLE(wxSplitterWindow, wxWindow)
  68     EVT_PAINT(wxSplitterWindow::OnPaint)
  69     EVT_SIZE(wxSplitterWindow::OnSize)
  70     EVT_MOUSE_EVENTS(wxSplitterWindow::OnMouseEvent)
  71
  72 #if defined( __WXMSW__ ) || defined( __WXMAC__)
  73     EVT_SET_CURSOR(wxSplitterWindow::OnSetCursor)
  74 #endif // wxMSW
  75
  76     WX_EVENT_TABLE_CONTROL_CONTAINER(wxSplitterWindow)
  77 END_EVENT_TABLE()
  78
  79 WX_DELEGATE_TO_CONTROL_CONTAINER(wxSplitterWindow);
  80
  81 bool wxSplitterWindow::Create(wxWindow *parent, wxWindowID id,
  82                                    const wxPoint& pos,
  83                                    const wxSize& size,
  84                                    long style,
  85                                    const wxString& name)
  86 {
  87     // allow TABbing from one window to the other
  88     style |= wxTAB_TRAVERSAL;
  89
  90     // we draw our border ourselves to blend the sash with it
  91     style &= ~wxBORDER_MASK;
  92     style |= wxBORDER_NONE;
  93
  94     if ( !wxWindow::Create(parent, id, pos, size, style, name) )
  95         return false;
  96
  97     m_permitUnsplitAlways = (style & wxSP_PERMIT_UNSPLIT) != 0;
  98
  99     // don't erase the splitter background, it's pointless as we overwrite it
 100     // anyhow
 101     SetBackgroundStyle(wxBG_STYLE_CUSTOM);
 102
 103     return true;
 104 }
 105
 106 void wxSplitterWindow::Init()
 107 {
 108     m_container.SetContainerWindow(this);
 109
 110     m_splitMode = wxSPLIT_VERTICAL;
 111     m_permitUnsplitAlways = true;
 112     m_windowOne = (wxWindow *) NULL;
 113     m_windowTwo = (wxWindow *) NULL;
 114     m_dragMode = wxSPLIT_DRAG_NONE;
 115     m_oldX = 0;
 116     m_oldY = 0;
 117     m_firstX = 0;
 118     m_firstY = 0;
 119     m_sashPosition = m_requestedSashPosition = 0;
 120     m_checkRequestedSashPosition = false;
 121     m_minimumPaneSize = 0;
 122     m_sashCursorWE = wxCursor(wxCURSOR_SIZEWE);
 123     m_sashCursorNS = wxCursor(wxCURSOR_SIZENS);
 124     m_sashTrackerPen = new wxPen(*wxBLACK, 2, wxSOLID);
 125
 126     m_needUpdating = false;
 127     m_isHot = false;
 128 }
 129
 130 wxSplitterWindow::~wxSplitterWindow()
 131 {
 132     delete m_sashTrackerPen;
 133 }
 134
 135 // ----------------------------------------------------------------------------
 136 // entering/leaving sash
 137 // ----------------------------------------------------------------------------
 138
 139 void wxSplitterWindow::RedrawIfHotSensitive(bool isHot)
 140 {
 141     if ( wxRendererNative::Get().GetSplitterParams(this).isHotSensitive )
 142     {
 143         m_isHot = isHot;
 144
 145         wxClientDC dc(this);
 146         DrawSash(dc);
 147     }
 148     //else: we don't change our appearance, don't redraw to avoid flicker
 149 }
 150
 151 void wxSplitterWindow::OnEnterSash()
 152 {
 153     SetResizeCursor();
 154
 155     RedrawIfHotSensitive(true);
 156 }
 157
 158 void wxSplitterWindow::OnLeaveSash()
 159 {
 160     SetCursor(*wxSTANDARD_CURSOR);
 161
 162     RedrawIfHotSensitive(false);
 163 }
 164
 165 void wxSplitterWindow::SetResizeCursor()
 166 {
 167     SetCursor(m_splitMode == wxSPLIT_VERTICAL ? m_sashCursorWE
 168                                               : m_sashCursorNS);
 169 }
 170
 171 // ----------------------------------------------------------------------------
 172 // other event handlers
 173 // ----------------------------------------------------------------------------
 174
 175 void wxSplitterWindow::OnPaint(wxPaintEvent& WXUNUSED(event))
 176 {
 177     wxPaintDC dc(this);
 178
 179     DrawSash(dc);
 180 }
 181
 182 void wxSplitterWindow::OnInternalIdle()
 183 {
 184     wxWindow::OnInternalIdle();
 185
 186     // if this is the first idle time after a sash position has potentially
 187     // been set, allow SizeWindows to check for a requested size.
 188     if (!m_checkRequestedSashPosition)
 189     {
 190         m_checkRequestedSashPosition = true;
 191         SizeWindows();
 192         return; // it won't needUpdating in this case
 193     }
 194
 195     if (m_needUpdating)
 196         SizeWindows();
 197 }
 198
 199 void wxSplitterWindow::OnMouseEvent(wxMouseEvent& event)
 200 {
 201     int x = (int)event.GetX(),
 202         y = (int)event.GetY();
 203
 204     if (GetWindowStyle() & wxSP_NOSASH)
 205         return;
 206
 207     // with wxSP_LIVE_UPDATE style the splitter windows are always resized
 208     // following the mouse movement while it drags the sash, without it we only
 209     // draw the sash at the new position but only resize the windows when the
 210     // dragging is finished
 211 #if defined( __WXMAC__ ) && TARGET_API_MAC_OSX == 1
 212     bool isLive = true ;
 213 #else
 214     bool isLive = (GetWindowStyleFlag() & wxSP_LIVE_UPDATE) != 0;
 215 #endif
 216     if (event.LeftDown())
 217     {
 218         if ( SashHitTest(x, y) )
 219         {
 220             // Start the drag now
 221             m_dragMode = wxSPLIT_DRAG_DRAGGING;
 222
 223             // Capture mouse and set the cursor
 224             CaptureMouse();
 225             SetResizeCursor();
 226
 227             if ( !isLive )
 228             {
 229                 // remember the initial sash position and draw the initial
 230                 // shadow sash
 231                 m_sashPositionCurrent = m_sashPosition;
 232
 233                 DrawSashTracker(x, y);
 234             }
 235
 236             m_oldX = x;
 237             m_oldY = y;
 238
 239             SetResizeCursor();
 240             return;
 241         }
 242     }
 243     else if (event.LeftUp() && m_dragMode == wxSPLIT_DRAG_DRAGGING)
 244     {
 245         // We can stop dragging now and see what we've got.
 246         m_dragMode = wxSPLIT_DRAG_NONE;
 247
 248         // Release mouse and unset the cursor
 249         ReleaseMouse();
 250         SetCursor(* wxSTANDARD_CURSOR);
 251
 252         // exit if unsplit after doubleclick
 253         if ( !IsSplit() )
 254         {
 255             return;
 256         }
 257
 258         // Erase old tracker
 259         if ( !isLive )
 260         {
 261             DrawSashTracker(m_oldX, m_oldY);
 262         }
 263
 264         // the position of the click doesn't exactly correspond to
 265         // m_sashPosition, rather it changes it by the distance by which the
 266         // mouse has moved
 267         int diff = m_splitMode == wxSPLIT_VERTICAL ? x - m_oldX : y - m_oldY;
 268
 269         int posSashOld = isLive ? m_sashPosition : m_sashPositionCurrent;
 270         int posSashNew = OnSashPositionChanging(posSashOld + diff);
 271         if ( posSashNew == -1 )
 272         {
 273             // change not allowed
 274             return;
 275         }
 276
 277         if ( m_permitUnsplitAlways || m_minimumPaneSize == 0 )
 278         {
 279             // Deal with possible unsplit scenarios
 280             if ( posSashNew == 0 )
 281             {
 282                 // We remove the first window from the view
 283                 wxWindow *removedWindow = m_windowOne;
 284                 m_windowOne = m_windowTwo;
 285                 m_windowTwo = (wxWindow *) NULL;
 286                 OnUnsplit(removedWindow);
 287                 wxSplitterEvent event(wxEVT_COMMAND_SPLITTER_UNSPLIT, this);
 288                 event.m_data.win = removedWindow;
 289                 (void)DoSendEvent(event);
 290                 SetSashPositionAndNotify(0);
 291             }
 292             else if ( posSashNew == GetWindowSize() )
 293             {
 294                 // We remove the second window from the view
 295                 wxWindow *removedWindow = m_windowTwo;
 296                 m_windowTwo = (wxWindow *) NULL;
 297                 OnUnsplit(removedWindow);
 298                 wxSplitterEvent event(wxEVT_COMMAND_SPLITTER_UNSPLIT, this);
 299                 event.m_data.win = removedWindow;
 300                 (void)DoSendEvent(event);
 301                 SetSashPositionAndNotify(0);
 302             }
 303             else
 304             {
 305                 SetSashPositionAndNotify(posSashNew);
 306             }
 307         }
 308         else
 309         {
 310             SetSashPositionAndNotify(posSashNew);
 311         }
 312
 313         SizeWindows();
 314     }  // left up && dragging
 315     else if ((event.Moving() || event.Leaving() || event.Entering()) && (m_dragMode == wxSPLIT_DRAG_NONE))
 316     {
 317         if ( event.Leaving() || !SashHitTest(x, y) )
 318             OnLeaveSash();
 319         else
 320             OnEnterSash();
 321     }
 322     else if (event.Dragging() && (m_dragMode == wxSPLIT_DRAG_DRAGGING))
 323     {
 324         int diff = m_splitMode == wxSPLIT_VERTICAL ? x - m_oldX : y - m_oldY;
 325         if ( !diff )
 326         {
 327             // nothing to do, mouse didn't really move far enough
 328             return;
 329         }
 330
 331         int posSashOld = isLive ? m_sashPosition : m_sashPositionCurrent;
 332         int posSashNew = OnSashPositionChanging(posSashOld + diff);
 333         if ( posSashNew == -1 )
 334         {
 335             // change not allowed
 336             return;
 337         }
 338
 339         if ( posSashNew == m_sashPosition )
 340             return;
 341
 342         // Erase old tracker
 343         if ( !isLive )
 344         {
 345             DrawSashTracker(m_oldX, m_oldY);
 346         }
 347
 348         if (m_splitMode == wxSPLIT_VERTICAL)
 349             x = posSashNew;
 350         else
 351             y = posSashNew;
 352
 353         // Remember old positions
 354         m_oldX = x;
 355         m_oldY = y;
 356
 357 #ifdef __WXMSW__
 358         // As we captured the mouse, we may get the mouse events from outside
 359         // our window - for example, negative values in x, y. This has a weird
 360         // consequence under MSW where we use unsigned values sometimes and
 361         // signed ones other times: the coordinates turn as big positive
 362         // numbers and so the sash is drawn on the *right* side of the window
 363         // instead of the left (or bottom instead of top). Correct this.
 364         if ( (short)m_oldX < 0 )
 365             m_oldX = 0;
 366         if ( (short)m_oldY < 0 )
 367             m_oldY = 0;
 368 #endif // __WXMSW__
 369
 370         // Draw new one
 371         if ( !isLive )
 372         {
 373             m_sashPositionCurrent = posSashNew;
 374
 375             DrawSashTracker(m_oldX, m_oldY);
 376         }
 377         else
 378         {
 379             SetSashPositionAndNotify(posSashNew);
 380             m_needUpdating = true;
 381         }
 382     }
 383     else if ( event.LeftDClick() && m_windowTwo )
 384     {
 385         OnDoubleClickSash(x, y);
 386     }
 387 }
 388
 389 void wxSplitterWindow::OnSize(wxSizeEvent& event)
 390 {
 391     // only process this message if we're not iconized - otherwise iconizing
 392     // and restoring a window containing the splitter has a funny side effect
 393     // of changing the splitter position!
 394     wxWindow *parent = wxGetTopLevelParent(this);
 395     bool iconized;
 396
 397     wxTopLevelWindow *winTop = wxDynamicCast(parent, wxTopLevelWindow);
 398     if ( winTop )
 399     {
 400         iconized = winTop->IsIconized();
 401     }
 402     else
 403     {
 404         wxFAIL_MSG(wxT("should have a top level parent!"));
 405
 406         iconized = false;
 407     }
 408
 409     if ( iconized )
 410     {
 411         event.Skip();
 412
 413         return;
 414     }
 415
 416     if ( m_windowTwo )
 417     {
 418         int w, h;
 419         GetClientSize(&w, &h);
 420
 421         int size = m_splitMode == wxSPLIT_VERTICAL ? w : h;
 422         if ( m_sashPosition >= size - 5 )
 423             SetSashPositionAndNotify(wxMax(10, size - 40));
 424     }
 425
 426     SizeWindows();
 427 }
 428
 429 bool wxSplitterWindow::SashHitTest(int x, int y, int tolerance)
 430 {
 431     if ( m_windowTwo == NULL || m_sashPosition == 0)
 432         return false; // No sash
 433
 434     int z = m_splitMode == wxSPLIT_VERTICAL ? x : y;
 435     int hitMin = m_sashPosition - tolerance;
 436     int hitMax = m_sashPosition + GetSashSize() + tolerance;
 437
 438     return z >=  hitMin && z <= hitMax;
 439 }
 440
 441 int wxSplitterWindow::GetSashSize() const
 442 {
 443     return wxRendererNative::Get().GetSplitterParams(this).widthSash;
 444 }
 445
 446 int wxSplitterWindow::GetBorderSize() const
 447 {
 448     return wxRendererNative::Get().GetSplitterParams(this).border;
 449 }
 450
 451 // Draw the sash
 452 void wxSplitterWindow::DrawSash(wxDC& dc)
 453 {
 454     if (HasFlag(wxSP_3DBORDER))
 455         wxRendererNative::Get().DrawSplitterBorder
 456                             (
 457                                 this,
 458                                 dc,
 459                                 GetClientRect()
 460                             );
 461
 462     // don't draw sash if we're not split
 463     if ( m_sashPosition == 0 || !m_windowTwo )
 464         return;
 465
 466     // nor if we're configured to not show it
 467     if ( HasFlag(wxSP_NOSASH) )
 468         return;
 469
 470     wxRendererNative::Get().DrawSplitterSash
 471                             (
 472                                 this,
 473                                 dc,
 474                                 GetClientSize(),
 475                                 m_sashPosition,
 476                                 m_splitMode == wxSPLIT_VERTICAL ? wxVERTICAL
 477                                                                 : wxHORIZONTAL,
 478                                 m_isHot ? wxCONTROL_CURRENT : 0
 479                             );
 480 }
 481
 482 // Draw the sash tracker (for whilst moving the sash)
 483 void wxSplitterWindow::DrawSashTracker(int x, int y)
 484 {
 485     int w, h;
 486     GetClientSize(&w, &h);
 487
 488     wxScreenDC screenDC;
 489     int x1, y1;
 490     int x2, y2;
 491
 492     if ( m_splitMode == wxSPLIT_VERTICAL )
 493     {
 494         x1 = x; y1 = 2;
 495         x2 = x; y2 = h-2;
 496
 497         if ( x1 > w )
 498         {
 499             x1 = w; x2 = w;
 500         }
 501         else if ( x1 < 0 )
 502         {
 503             x1 = 0; x2 = 0;
 504         }
 505     }
 506     else
 507     {
 508         x1 = 2; y1 = y;
 509         x2 = w-2; y2 = y;
 510
 511         if ( y1 > h )
 512         {
 513             y1 = h;
 514             y2 = h;
 515         }
 516         else if ( y1 < 0 )
 517         {
 518             y1 = 0;
 519             y2 = 0;
 520         }
 521     }
 522
 523     ClientToScreen(&x1, &y1);
 524     ClientToScreen(&x2, &y2);
 525
 526     screenDC.SetLogicalFunction(wxINVERT);
 527     screenDC.SetPen(*m_sashTrackerPen);
 528     screenDC.SetBrush(*wxTRANSPARENT_BRUSH);
 529
 530     screenDC.DrawLine(x1, y1, x2, y2);
 531
 532     screenDC.SetLogicalFunction(wxCOPY);
 533 }
 534
 535 int wxSplitterWindow::GetWindowSize() const
 536 {
 537     wxSize size = GetClientSize();
 538
 539     return m_splitMode == wxSPLIT_VERTICAL ? size.x : size.y;
 540 }
 541
 542 int wxSplitterWindow::AdjustSashPosition(int sashPos) const
 543 {
 544     int window_size = GetWindowSize();
 545
 546     wxWindow *win;
 547
 548     win = GetWindow1();
 549     if ( win )
 550     {
 551         // the window shouldn't be smaller than its own minimal size nor
 552         // smaller than the minimual pane size specified for this splitter
 553         int minSize = m_splitMode == wxSPLIT_VERTICAL ? win->GetMinWidth()
 554                                                       : win->GetMinHeight();
 555
 556         if ( minSize == -1 || m_minimumPaneSize > minSize )
 557             minSize = m_minimumPaneSize;
 558
 559         minSize += GetBorderSize();
 560
 561         if ( sashPos < minSize )
 562             sashPos = minSize;
 563     }
 564
 565     win = GetWindow2();
 566     if ( win )
 567     {
 568         int minSize = m_splitMode == wxSPLIT_VERTICAL ? win->GetMinWidth()
 569                                                       : win->GetMinHeight();
 570
 571         if ( minSize == -1 || m_minimumPaneSize > minSize )
 572             minSize = m_minimumPaneSize;
 573
 574         int maxSize = window_size - minSize - GetBorderSize() - GetSashSize();
 575         if ( sashPos > maxSize )
 576             sashPos = maxSize;
 577     }
 578
 579     return sashPos;
 580 }
 581
 582 bool wxSplitterWindow::DoSetSashPosition(int sashPos)
 583 {
 584     int newSashPosition = AdjustSashPosition(sashPos);
 585
 586     if ( newSashPosition == m_sashPosition )
 587         return false;
 588
 589     m_sashPosition = newSashPosition;
 590
 591     return true;
 592 }
 593
 594 void wxSplitterWindow::SetSashPositionAndNotify(int sashPos)
 595 {
 596     // we must reset the request here, otherwise the sash would be stuck at
 597     // old position if the user attempted to move the sash after invalid
 598     // (e.g. smaller than minsize) sash position was requested using
 599     // SetSashPosition():
 600     m_requestedSashPosition = INT_MAX;
 601
 602     if ( DoSetSashPosition(sashPos) )
 603     {
 604         wxSplitterEvent event(wxEVT_COMMAND_SPLITTER_SASH_POS_CHANGED, this);
 605         event.m_data.pos = m_sashPosition;
 606
 607         (void)DoSendEvent(event);
 608     }
 609 }
 610
 611 // Position and size subwindows.
 612 // Note that the border size applies to each subwindow, not
 613 // including the edges next to the sash.
 614 void wxSplitterWindow::SizeWindows()
 615 {
 616     // check if we have delayed setting the real sash position
 617     if ( m_checkRequestedSashPosition && m_requestedSashPosition != INT_MAX )
 618     {
 619         int newSashPosition = ConvertSashPosition(m_requestedSashPosition);
 620         if ( newSashPosition != m_sashPosition )
 621         {
 622             DoSetSashPosition(newSashPosition);
 623         }
 624
 625         if ( newSashPosition <= m_sashPosition
 626             && newSashPosition >= m_sashPosition - GetBorderSize() )
 627         {
 628             // don't update it any more
 629             m_requestedSashPosition = INT_MAX;
 630         }
 631     }
 632
 633     int w, h;
 634     GetClientSize(&w, &h);
 635
 636     if ( GetWindow1() && !GetWindow2() )
 637     {
 638         GetWindow1()->SetSize(GetBorderSize(), GetBorderSize(),
 639                               w - 2*GetBorderSize(), h - 2*GetBorderSize());
 640     }
 641     else if ( GetWindow1() && GetWindow2() )
 642     {
 643         const int border = GetBorderSize(),
 644                   sash = GetSashSize();
 645
 646         int size1 = GetSashPosition() - border,
 647             size2 = GetSashPosition() + sash;
 648
 649         int x2, y2, w1, h1, w2, h2;
 650         if ( GetSplitMode() == wxSPLIT_VERTICAL )
 651         {
 652             w1 = size1;
 653             w2 = w - 2*border - sash - w1;
 654             h1 =
 655             h2 = h - 2*border;
 656             x2 = size2;
 657             y2 = border;
 658         }
 659         else // horz splitter
 660         {
 661             w1 =
 662             w2 = w - 2*border;
 663             h1 = size1;
 664             h2 = h - 2*border - sash - h1;
 665             x2 = border;
 666             y2 = size2;
 667         }
 668
 669         GetWindow1()->SetSize(border, border, w1, h1);
 670         GetWindow2()->SetSize(x2, y2, w2, h2);
 671     }
 672
 673     wxClientDC dc(this);
 674     DrawSash(dc);
 675
 676     SetNeedUpdating(false);
 677 }
 678
 679 // Set pane for unsplit window
 680 void wxSplitterWindow::Initialize(wxWindow *window)
 681 {
 682     wxASSERT_MSG( (!window || (window && window->GetParent() == this)),
 683                   _T("windows in the splitter should have it as parent!") );
 684
 685     m_windowOne = window;
 686     m_windowTwo = (wxWindow *) NULL;
 687     DoSetSashPosition(0);
 688 }
 689
 690 // Associates the given window with window 2, drawing the appropriate sash
 691 // and changing the split mode.
 692 // Does nothing and returns false if the window is already split.
 693 bool wxSplitterWindow::DoSplit(wxSplitMode mode,
 694                                wxWindow *window1, wxWindow *window2,
 695                                int sashPosition)
 696 {
 697     if ( IsSplit() )
 698         return false;
 699
 700     wxCHECK_MSG( window1 && window2, false,
 701                  _T("can not split with NULL window(s)") );
 702
 703     wxCHECK_MSG( window1->GetParent() == this && window2->GetParent() == this, false,
 704                   _T("windows in the splitter should have it as parent!") );
 705
 706     m_splitMode = mode;
 707     m_windowOne = window1;
 708     m_windowTwo = window2;
 709
 710     // remember the sash position we want to set for later if we can't set it
 711     // right now (e.g. because the window is too small)
 712     m_requestedSashPosition = sashPosition;
 713     m_checkRequestedSashPosition = false;
 714
 715     DoSetSashPosition(ConvertSashPosition(sashPosition));
 716
 717     SizeWindows();
 718
 719     return true;
 720 }
 721
 722 int wxSplitterWindow::ConvertSashPosition(int sashPosition) const
 723 {
 724     if ( sashPosition > 0 )
 725     {
 726         return sashPosition;
 727     }
 728     else if ( sashPosition < 0 )
 729     {
 730         // It's negative so adding is subtracting
 731         return GetWindowSize() + sashPosition;
 732     }
 733     else // sashPosition == 0
 734     {
 735         // default, put it in the centre
 736         return GetWindowSize() / 2;
 737     }
 738 }
 739
 740 // Remove the specified (or second) window from the view
 741 // Doesn't actually delete the window.
 742 bool wxSplitterWindow::Unsplit(wxWindow *toRemove)
 743 {
 744     if ( ! IsSplit() )
 745         return false;
 746
 747     wxWindow *win;
 748     if ( toRemove == NULL || toRemove == m_windowTwo)
 749     {
 750         win = m_windowTwo ;
 751         m_windowTwo = (wxWindow *) NULL;
 752     }
 753     else if ( toRemove == m_windowOne )
 754     {
 755         win = m_windowOne ;
 756         m_windowOne = m_windowTwo;
 757         m_windowTwo = (wxWindow *) NULL;
 758     }
 759     else
 760     {
 761         wxFAIL_MSG(wxT("splitter: attempt to remove a non-existent window"));
 762
 763         return false;
 764     }
 765
 766     OnUnsplit(win);
 767     DoSetSashPosition(0);
 768     SizeWindows();
 769
 770     return true;
 771 }
 772
 773 // Replace a window with another one
 774 bool wxSplitterWindow::ReplaceWindow(wxWindow *winOld, wxWindow *winNew)
 775 {
 776     wxCHECK_MSG( winOld, false, wxT("use one of Split() functions instead") );
 777     wxCHECK_MSG( winNew, false, wxT("use Unsplit() functions instead") );
 778
 779     if ( winOld == m_windowTwo )
 780     {
 781         m_windowTwo = winNew;
 782     }
 783     else if ( winOld == m_windowOne )
 784     {
 785         m_windowOne = winNew;
 786     }
 787     else
 788     {
 789         wxFAIL_MSG(wxT("splitter: attempt to replace a non-existent window"));
 790
 791         return false;
 792     }
 793
 794     SizeWindows();
 795
 796     return true;
 797 }
 798
 799 void wxSplitterWindow::SetMinimumPaneSize(int min)
 800 {
 801     m_minimumPaneSize = min;
 802     int pos = m_requestedSashPosition != INT_MAX ? m_requestedSashPosition : m_sashPosition;
 803     SetSashPosition(pos); // re-check limits
 804 }
 805
 806 void wxSplitterWindow::SetSashPosition(int position, bool redraw)
 807 {
 808     // remember the sash position we want to set for later if we can't set it
 809     // right now (e.g. because the window is too small)
 810     m_requestedSashPosition = position;
 811     m_checkRequestedSashPosition = false;
 812
 813     DoSetSashPosition(ConvertSashPosition(position));
 814
 815     if ( redraw )
 816     {
 817         SizeWindows();
 818     }
 819 }
 820
 821 // Make sure the child window sizes are updated. This is useful
 822 // for reducing flicker by updating the sizes before a
 823 // window is shown, if you know the overall size is correct.
 824 void wxSplitterWindow::UpdateSize()
 825 {
 826     m_checkRequestedSashPosition = true;
 827     SizeWindows();
 828     m_checkRequestedSashPosition = false;
 829 }
 830
 831 bool wxSplitterWindow::DoSendEvent(wxSplitterEvent& event)
 832 {
 833     return !GetEventHandler()->ProcessEvent(event) || event.IsAllowed();
 834 }
 835
 836 // ---------------------------------------------------------------------------
 837 // wxSplitterWindow virtual functions: they now just generate the events
 838 // ---------------------------------------------------------------------------
 839
 840 bool wxSplitterWindow::OnSashPositionChange(int WXUNUSED(newSashPosition))
 841 {
 842     // always allow by default
 843     return true;
 844 }
 845
 846 int wxSplitterWindow::OnSashPositionChanging(int newSashPosition)
 847 {
 848     // If within UNSPLIT_THRESHOLD from edge, set to edge to cause closure.
 849     const int UNSPLIT_THRESHOLD = 4;
 850
 851     // first of all, check if OnSashPositionChange() doesn't forbid this change
 852     if ( !OnSashPositionChange(newSashPosition) )
 853     {
 854         // it does
 855         return -1;
 856     }
 857
 858     // Obtain relevant window dimension for bottom / right threshold check
 859     int window_size = GetWindowSize();
 860
 861     bool unsplit_scenario = false;
 862     if ( m_permitUnsplitAlways || m_minimumPaneSize == 0 )
 863     {
 864         // Do edge detection if unsplit premitted
 865         if ( newSashPosition <= UNSPLIT_THRESHOLD )
 866         {
 867             // threshold top / left check
 868             newSashPosition = 0;
 869             unsplit_scenario = true;
 870         }
 871         if ( newSashPosition >= window_size - UNSPLIT_THRESHOLD )
 872         {
 873             // threshold bottom/right check
 874             newSashPosition = window_size;
 875             unsplit_scenario = true;
 876         }
 877     }
 878
 879     if ( !unsplit_scenario )
 880     {
 881         // If resultant pane would be too small, enlarge it
 882         newSashPosition = AdjustSashPosition(newSashPosition);
 883     }
 884
 885     // If the result is out of bounds it means minimum size is too big,
 886     // so split window in half as best compromise.
 887     if ( newSashPosition < 0 || newSashPosition > window_size )
 888         newSashPosition = window_size / 2;
 889
 890     // now let the event handler have it
 891     //
 892     // FIXME: shouldn't we do it before the adjustments above so as to ensure
 893     //        that the sash position is always reasonable?
 894     wxSplitterEvent event(wxEVT_COMMAND_SPLITTER_SASH_POS_CHANGING, this);
 895     event.m_data.pos = newSashPosition;
 896
 897     if ( !DoSendEvent(event) )
 898     {
 899         // the event handler vetoed the change
 900         newSashPosition = -1;
 901     }
 902     else
 903     {
 904         // it could have been changed by it
 905         newSashPosition = event.GetSashPosition();
 906     }
 907
 908     return newSashPosition;
 909 }
 910
 911 // Called when the sash is double-clicked. The default behaviour is to remove
 912 // the sash if the minimum pane size is zero.
 913 void wxSplitterWindow::OnDoubleClickSash(int x, int y)
 914 {
 915     wxCHECK_RET(m_windowTwo, wxT("splitter: no window to remove"));
 916
 917     // new code should handle events instead of using the virtual functions
 918     wxSplitterEvent event(wxEVT_COMMAND_SPLITTER_DOUBLECLICKED, this);
 919     event.m_data.pt.x = x;
 920     event.m_data.pt.y = y;
 921     if ( DoSendEvent(event) )
 922     {
 923         if ( GetMinimumPaneSize() == 0 || m_permitUnsplitAlways )
 924         {
 925             wxWindow* win = m_windowTwo;
 926             if ( Unsplit(win) )
 927             {
 928                 wxSplitterEvent unsplitEvent(wxEVT_COMMAND_SPLITTER_UNSPLIT, this);
 929                 unsplitEvent.m_data.win = win;
 930                 (void)DoSendEvent(unsplitEvent);
 931             }
 932         }
 933     }
 934     //else: blocked by user
 935 }
 936
 937 void wxSplitterWindow::OnUnsplit(wxWindow *winRemoved)
 938 {
 939     // call this before calling the event handler which may delete the window
 940     winRemoved->Show(false);
 941 }
 942
 943 #if defined( __WXMSW__ ) || defined( __WXMAC__)
 944
 945 // this is currently called (and needed) under MSW only...
 946 void wxSplitterWindow::OnSetCursor(wxSetCursorEvent& event)
 947 {
 948     // if we don't do it, the resizing cursor might be set for child window:
 949     // and like this we explicitly say that our cursor should not be used for
 950     // children windows which overlap us
 951
 952     if ( SashHitTest(event.GetX(), event.GetY(), 0) )
 953     {
 954         // default processing is ok
 955         event.Skip();
 956     }
 957     //else: do nothing, in particular, don't call Skip()
 958 }
 959
 960 #endif // wxMSW || wxMac
 961
 962 #endif // wxUSE_SPLITTER
 963