src/gtk1/scrolwin.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        gtk/scrolwin.cpp
   3 // Purpose:     wxScrolledWindow implementation
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     01/02/97
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Julian Smart and Markus Holzem
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #ifdef __GNUG__
  21     #pragma implementation "scrolwin.h"
  22 #endif
  23
  24 // For compilers that support precompilation, includes "wx.h".
  25 #include "wx/wxprec.h"
  26
  27 #ifdef __BORLANDC__
  28     #pragma hdrstop
  29 #endif
  30
  31 #include "wx/utils.h"
  32 #include "wx/dcclient.h"
  33
  34 #include "wx/gtk/scrolwin.h"
  35 #include "wx/panel.h"
  36
  37 #include <gtk/gtk.h>
  38 #include "wx/gtk/win_gtk.h"
  39
  40 // ----------------------------------------------------------------------------
  41 // event tables
  42 // ----------------------------------------------------------------------------
  43
  44 BEGIN_EVENT_TABLE(wxScrolledWindow, wxPanel)
  45     EVT_SCROLLWIN(wxScrolledWindow::OnScroll)
  46     EVT_SIZE(wxScrolledWindow::OnSize)
  47     EVT_PAINT(wxScrolledWindow::OnPaint)
  48     EVT_CHAR(wxScrolledWindow::OnChar)
  49 END_EVENT_TABLE()
  50
  51 IMPLEMENT_DYNAMIC_CLASS(wxScrolledWindow, wxPanel)
  52
  53 // ============================================================================
  54 // implementation
  55 // ============================================================================
  56
  57 //-----------------------------------------------------------------------------
  58 // data
  59 //-----------------------------------------------------------------------------
  60
  61 extern bool       g_blockEventsOnDrag;
  62
  63 //-----------------------------------------------------------------------------
  64 // idle system
  65 //-----------------------------------------------------------------------------
  66
  67 extern void wxapp_install_idle_handler();
  68 extern bool g_isIdle;
  69
  70 //-----------------------------------------------------------------------------
  71 // "value_changed" from m_vAdjust
  72 //-----------------------------------------------------------------------------
  73
  74 static void gtk_scrolled_window_vscroll_callback( GtkAdjustment *adjust, wxScrolledWindow *win )
  75 {
  76     if (g_isIdle)
  77         wxapp_install_idle_handler();
  78
  79     if (g_blockEventsOnDrag) return;
  80
  81     if (!win->m_hasVMT) return;
  82
  83     win->GtkVScroll( adjust->value );
  84 }
  85
  86 //-----------------------------------------------------------------------------
  87 // "value_changed" from m_hAdjust
  88 //-----------------------------------------------------------------------------
  89
  90 static void gtk_scrolled_window_hscroll_callback( GtkAdjustment *adjust, wxScrolledWindow *win )
  91 {
  92     if (g_isIdle)
  93         wxapp_install_idle_handler();
  94
  95     if (g_blockEventsOnDrag) return;
  96     if (!win->m_hasVMT) return;
  97
  98     win->GtkHScroll( adjust->value );
  99 }
 100
 101 //-----------------------------------------------------------------------------
 102 // InsertChild for wxScrolledWindow
 103 //-----------------------------------------------------------------------------
 104
 105 static void wxInsertChildInScrolledWindow( wxWindow* parent, wxWindow* child )
 106 {
 107     // The window might have been scrolled already, do we
 108     // have to adapt the position.
 109     GtkPizza *pizza = GTK_PIZZA(parent->m_wxwindow);
 110     child->m_x += pizza->xoffset;
 111     child->m_y += pizza->yoffset;
 112
 113     gtk_pizza_put( GTK_PIZZA(parent->m_wxwindow),
 114                      GTK_WIDGET(child->m_widget),
 115                      child->m_x,
 116                      child->m_y,
 117                      child->m_width,
 118                      child->m_height );
 119 }
 120
 121 // ----------------------------------------------------------------------------
 122 // wxScrolledWindow creation
 123 // ----------------------------------------------------------------------------
 124
 125 void wxScrolledWindow::Init()
 126 {
 127     m_xScrollPixelsPerLine = 0;
 128     m_yScrollPixelsPerLine = 0;
 129     m_xScrollingEnabled = TRUE;
 130     m_yScrollingEnabled = TRUE;
 131     m_xScrollPosition = 0;
 132     m_yScrollPosition = 0;
 133     m_xScrollLines = 0;
 134     m_yScrollLines = 0;
 135     m_xScrollLinesPerPage = 0;
 136     m_yScrollLinesPerPage = 0;
 137     m_targetWindow = (wxWindow*) NULL;
 138     m_scaleX = 1.0;
 139     m_scaleY = 1.0;
 140     m_hasScrolling = TRUE;
 141 }
 142
 143 bool wxScrolledWindow::Create(wxWindow *parent,
 144                               wxWindowID id,
 145                               const wxPoint& pos,
 146                               const wxSize& size,
 147                               long style,
 148                               const wxString& name)
 149 {
 150     Init();
 151
 152     if (!PreCreation( parent, pos, size ) ||
 153         !CreateBase( parent, id, pos, size, style, wxDefaultValidator, name ))
 154     {
 155         wxFAIL_MSG( wxT("wxWindow creation failed") );
 156         return FALSE;
 157     }
 158
 159     m_insertCallback = wxInsertChildInScrolledWindow;
 160
 161     m_targetWindow = this;
 162
 163     m_widget = gtk_scrolled_window_new( (GtkAdjustment *) NULL, (GtkAdjustment *) NULL );
 164     GTK_WIDGET_UNSET_FLAGS( m_widget, GTK_CAN_FOCUS );
 165
 166     GtkScrolledWindow *scrolledWindow = GTK_SCROLLED_WINDOW(m_widget);
 167
 168     GtkScrolledWindowClass *scroll_class = GTK_SCROLLED_WINDOW_CLASS( GTK_OBJECT_GET_CLASS(m_widget) );
 169     scroll_class->scrollbar_spacing = 0;
 170
 171     gtk_scrolled_window_set_policy( scrolledWindow, GTK_POLICY_AUTOMATIC, GTK_POLICY_AUTOMATIC );
 172
 173     m_hAdjust = gtk_range_get_adjustment( GTK_RANGE(scrolledWindow->hscrollbar) );
 174     m_vAdjust = gtk_range_get_adjustment( GTK_RANGE(scrolledWindow->vscrollbar) );
 175
 176     m_wxwindow = gtk_pizza_new();
 177
 178     gtk_container_add( GTK_CONTAINER(m_widget), m_wxwindow );
 179
 180     GtkPizza *pizza = GTK_PIZZA(m_wxwindow);
 181
 182     if (HasFlag(wxRAISED_BORDER))
 183     {
 184         gtk_pizza_set_shadow_type( pizza, GTK_MYSHADOW_OUT );
 185     }
 186     else if (HasFlag(wxSUNKEN_BORDER))
 187     {
 188         gtk_pizza_set_shadow_type( pizza, GTK_MYSHADOW_IN );
 189     }
 190     else if (HasFlag(wxSIMPLE_BORDER))
 191     {
 192         gtk_pizza_set_shadow_type( pizza, GTK_MYSHADOW_THIN );
 193     }
 194     else
 195     {
 196         gtk_pizza_set_shadow_type( pizza, GTK_MYSHADOW_NONE );
 197     }
 198
 199     GTK_WIDGET_SET_FLAGS( m_wxwindow, GTK_CAN_FOCUS );
 200     m_acceptsFocus = TRUE;
 201
 202     // I _really_ don't want scrollbars in the beginning
 203     m_vAdjust->lower = 0.0;
 204     m_vAdjust->upper = 1.0;
 205     m_vAdjust->value = 0.0;
 206     m_vAdjust->step_increment = 1.0;
 207     m_vAdjust->page_increment = 1.0;
 208     gtk_signal_emit_by_name( GTK_OBJECT(m_vAdjust), "changed" );
 209     m_hAdjust->lower = 0.0;
 210     m_hAdjust->upper = 1.0;
 211     m_hAdjust->value = 0.0;
 212     m_hAdjust->step_increment = 1.0;
 213     m_hAdjust->page_increment = 1.0;
 214     gtk_signal_emit_by_name( GTK_OBJECT(m_hAdjust), "changed" );
 215
 216     // Handlers for new scrollbar values
 217     GtkVConnectEvent();
 218     GtkHConnectEvent();
 219
 220     gtk_widget_show( m_wxwindow );
 221
 222     if (m_parent)
 223         m_parent->DoAddChild( this );
 224
 225     PostCreation();
 226
 227     Show( TRUE );
 228
 229     return TRUE;
 230 }
 231
 232 // ----------------------------------------------------------------------------
 233 // setting scrolling parameters
 234 // ----------------------------------------------------------------------------
 235
 236 /*
 237  * pixelsPerUnitX/pixelsPerUnitY: number of pixels per unit (e.g. pixels per text line)
 238  * noUnitsX/noUnitsY:        : no. units per scrollbar
 239  */
 240 void wxScrolledWindow::SetScrollbars (int pixelsPerUnitX, int pixelsPerUnitY,
 241                int noUnitsX, int noUnitsY,
 242                int xPos, int yPos, bool noRefresh )
 243 {
 244     int old_x = m_xScrollPixelsPerLine * m_xScrollPosition;
 245     int old_y = m_yScrollPixelsPerLine * m_yScrollPosition;
 246
 247     m_xScrollPixelsPerLine = pixelsPerUnitX;
 248     m_yScrollPixelsPerLine = pixelsPerUnitY;
 249     m_xScrollLines = noUnitsX;
 250     m_yScrollLines = noUnitsY;
 251     m_xScrollPosition = xPos;
 252     m_yScrollPosition = yPos;
 253
 254     m_hAdjust->lower = 0.0;
 255     m_hAdjust->upper = noUnitsX;
 256     m_hAdjust->value = xPos;
 257     m_hAdjust->step_increment = 1.0;
 258     m_hAdjust->page_increment = 2.0;
 259
 260     m_vAdjust->lower = 0.0;
 261     m_vAdjust->upper = noUnitsY;
 262     m_vAdjust->value = yPos;
 263     m_vAdjust->step_increment = 1.0;
 264     m_vAdjust->page_increment = 2.0;
 265
 266     AdjustScrollbars();
 267
 268     if (!noRefresh)
 269     {
 270         int new_x = m_xScrollPixelsPerLine * m_xScrollPosition;
 271         int new_y = m_yScrollPixelsPerLine * m_yScrollPosition;
 272
 273         m_targetWindow->ScrollWindow( old_x-new_x, old_y-new_y );
 274     }
 275 }
 276
 277 void wxScrolledWindow::AdjustScrollbars()
 278 {
 279     int w, h;
 280     m_targetWindow->GetClientSize( &w, &h );
 281
 282     if (m_xScrollPixelsPerLine == 0)
 283         m_hAdjust->page_size = 1.0;
 284     else
 285         m_hAdjust->page_size = (w / m_xScrollPixelsPerLine);
 286
 287     if (m_yScrollPixelsPerLine == 0)
 288         m_vAdjust->page_size = 1.0;
 289     else
 290         m_vAdjust->page_size = (h / m_yScrollPixelsPerLine);
 291
 292     m_xScrollLinesPerPage = (int)(m_hAdjust->page_size + 0.5);
 293     m_yScrollLinesPerPage = (int)(m_vAdjust->page_size + 0.5);
 294
 295     gtk_signal_emit_by_name( GTK_OBJECT(m_vAdjust), "changed" );
 296     gtk_signal_emit_by_name( GTK_OBJECT(m_hAdjust), "changed" );
 297 }
 298
 299 // ----------------------------------------------------------------------------
 300 // target window handling
 301 // ----------------------------------------------------------------------------
 302
 303 void wxScrolledWindow::SetTargetWindow( wxWindow *target )
 304 {
 305     wxASSERT_MSG( target, wxT("target window must not be NULL") );
 306     m_targetWindow = target;
 307 }
 308
 309 wxWindow *wxScrolledWindow::GetTargetWindow()
 310 {
 311     return m_targetWindow;
 312 }
 313
 314 // Override this function if you don't want to have wxScrolledWindow
 315 // automatically change the origin according to the scroll position.
 316 void wxScrolledWindow::PrepareDC(wxDC& dc)
 317 {
 318     dc.SetDeviceOrigin( -m_xScrollPosition * m_xScrollPixelsPerLine,
 319                         -m_yScrollPosition * m_yScrollPixelsPerLine );
 320 }
 321
 322 void wxScrolledWindow::GetScrollPixelsPerUnit (int *x_unit, int *y_unit) const
 323 {
 324     if ( x_unit )
 325         *x_unit = m_xScrollPixelsPerLine;
 326     if ( y_unit )
 327         *y_unit = m_yScrollPixelsPerLine;
 328 }
 329
 330 int wxScrolledWindow::GetScrollPageSize(int orient) const
 331 {
 332     if ( orient == wxHORIZONTAL )
 333         return m_xScrollLinesPerPage;
 334     else
 335         return m_yScrollLinesPerPage;
 336 }
 337
 338 void wxScrolledWindow::SetScrollPageSize(int orient, int pageSize)
 339 {
 340     if ( orient == wxHORIZONTAL )
 341         m_xScrollLinesPerPage = pageSize;
 342     else
 343         m_yScrollLinesPerPage = pageSize;
 344 }
 345
 346 void wxScrolledWindow::OnScroll(wxScrollWinEvent& event)
 347 {
 348     int orient = event.GetOrientation();
 349
 350     int nScrollInc = CalcScrollInc(event);
 351     if (nScrollInc == 0) return;
 352
 353     if (orient == wxHORIZONTAL)
 354     {
 355         int newPos = m_xScrollPosition + nScrollInc;
 356         SetScrollPos(wxHORIZONTAL, newPos, TRUE );
 357     }
 358     else
 359     {
 360         int newPos = m_yScrollPosition + nScrollInc;
 361         SetScrollPos(wxVERTICAL, newPos, TRUE );
 362     }
 363
 364     if (orient == wxHORIZONTAL)
 365     {
 366         m_xScrollPosition += nScrollInc;
 367     }
 368     else
 369     {
 370         m_yScrollPosition += nScrollInc;
 371     }
 372
 373     if (orient == wxHORIZONTAL)
 374     {
 375        if (m_xScrollingEnabled)
 376             m_targetWindow->ScrollWindow(-m_xScrollPixelsPerLine * nScrollInc, 0, (const wxRect *) NULL);
 377        else
 378             m_targetWindow->Refresh();
 379     }
 380     else
 381     {
 382         if (m_yScrollingEnabled)
 383             m_targetWindow->ScrollWindow(0, -m_yScrollPixelsPerLine * nScrollInc, (const wxRect *) NULL);
 384         else
 385             m_targetWindow->Refresh();
 386     }
 387 }
 388
 389 void wxScrolledWindow::Scroll( int x_pos, int y_pos )
 390 {
 391     if (!m_targetWindow)
 392         return;
 393
 394     if (((x_pos == -1) || (x_pos == m_xScrollPosition)) &&
 395         ((y_pos == -1) || (y_pos == m_yScrollPosition))) return;
 396
 397     if ((x_pos != -1) && (m_xScrollPixelsPerLine))
 398     {
 399         int max = (int)(m_hAdjust->upper - m_hAdjust->page_size + 0.5);
 400         if (max < 0) max = 0;
 401         if (x_pos > max) x_pos = max;
 402         if (x_pos < 0) x_pos = 0;
 403
 404         int old_x = m_xScrollPosition;
 405         m_xScrollPosition = x_pos;
 406         m_hAdjust->value = x_pos;
 407
 408         m_targetWindow->ScrollWindow( (old_x-m_xScrollPosition)*m_xScrollPixelsPerLine, 0 );
 409
 410         // Just update the scrollbar, don't send any wxWindows event
 411         GtkHDisconnectEvent();
 412         gtk_signal_emit_by_name( GTK_OBJECT(m_hAdjust), "value_changed" );
 413         GtkHConnectEvent();
 414     }
 415
 416     if ((y_pos != -1) && (m_yScrollPixelsPerLine))
 417     {
 418         int max = (int)(m_vAdjust->upper - m_vAdjust->page_size + 0.5);
 419         if (max < 0) max = 0;
 420         if (y_pos > max) y_pos = max;
 421         if (y_pos < 0) y_pos = 0;
 422
 423         int old_y = m_yScrollPosition;
 424         m_yScrollPosition = y_pos;
 425         m_vAdjust->value = y_pos;
 426
 427         m_targetWindow->ScrollWindow( 0, (old_y-m_yScrollPosition)*m_yScrollPixelsPerLine );
 428
 429         // Just update the scrollbar, don't send any wxWindows event
 430         GtkVDisconnectEvent();
 431         gtk_signal_emit_by_name( GTK_OBJECT(m_vAdjust), "value_changed" );
 432         GtkVConnectEvent();
 433     }
 434 }
 435
 436 void wxScrolledWindow::GtkVScroll( float value )
 437 {
 438     if (!m_targetWindow)
 439         return;
 440
 441     if (m_yScrollPixelsPerLine == 0)
 442         return;
 443
 444     int y_pos = (int)(value+0.5);
 445
 446     if (y_pos == m_yScrollPosition)
 447         return;
 448
 449     GtkScrolledWindow *scrolledWindow = GTK_SCROLLED_WINDOW(m_widget);
 450     GtkRange *range = GTK_RANGE(scrolledWindow->vscrollbar);
 451
 452     wxEventType command = wxEVT_SCROLLWIN_THUMBTRACK;
 453     if      (range->scroll_type == GTK_SCROLL_STEP_BACKWARD) command = wxEVT_SCROLLWIN_LINEUP;
 454     else if (range->scroll_type == GTK_SCROLL_STEP_FORWARD)  command = wxEVT_SCROLLWIN_LINEDOWN;
 455     else if (range->scroll_type == GTK_SCROLL_PAGE_BACKWARD) command = wxEVT_SCROLLWIN_PAGEUP;
 456     else if (range->scroll_type == GTK_SCROLL_PAGE_FORWARD)  command = wxEVT_SCROLLWIN_PAGEDOWN;
 457
 458     wxScrollWinEvent event( command, y_pos, wxVERTICAL );
 459     event.SetEventObject( this );
 460     GetEventHandler()->ProcessEvent( event );
 461 }
 462
 463 void wxScrolledWindow::GtkHScroll( float value )
 464 {
 465     if (!m_targetWindow)
 466         return;
 467
 468     if (m_xScrollPixelsPerLine == 0)
 469         return;
 470
 471     int x_pos = (int)(value+0.5);
 472
 473     if (x_pos == m_xScrollPosition)
 474         return;
 475
 476     GtkScrolledWindow *scrolledWindow = GTK_SCROLLED_WINDOW(m_widget);
 477     GtkRange *range = GTK_RANGE(scrolledWindow->hscrollbar);
 478
 479     wxEventType command = wxEVT_SCROLLWIN_THUMBTRACK;
 480     if      (range->scroll_type == GTK_SCROLL_STEP_BACKWARD) command = wxEVT_SCROLLWIN_LINEUP;
 481     else if (range->scroll_type == GTK_SCROLL_STEP_FORWARD)  command = wxEVT_SCROLLWIN_LINEDOWN;
 482     else if (range->scroll_type == GTK_SCROLL_PAGE_BACKWARD) command = wxEVT_SCROLLWIN_PAGEUP;
 483     else if (range->scroll_type == GTK_SCROLL_PAGE_FORWARD)  command = wxEVT_SCROLLWIN_PAGEDOWN;
 484
 485     wxScrollWinEvent event( command, x_pos, wxHORIZONTAL );
 486     event.SetEventObject( this );
 487     GetEventHandler()->ProcessEvent( event );
 488 }
 489
 490 void wxScrolledWindow::EnableScrolling (bool x_scroll, bool y_scroll)
 491 {
 492     m_xScrollingEnabled = x_scroll;
 493     m_yScrollingEnabled = y_scroll;
 494 }
 495
 496 void wxScrolledWindow::GetVirtualSize (int *x, int *y) const
 497 {
 498     if ( x )
 499         *x = m_xScrollPixelsPerLine * m_xScrollLines;
 500     if ( y )
 501         *y = m_yScrollPixelsPerLine * m_yScrollLines;
 502 }
 503
 504 // Where the current view starts from
 505 void wxScrolledWindow::GetViewStart (int *x, int *y) const
 506 {
 507     if ( x )
 508         *x = m_xScrollPosition;
 509     if ( y )
 510         *y = m_yScrollPosition;
 511 }
 512
 513 void wxScrolledWindow::CalcScrolledPosition(int x, int y, int *xx, int *yy) const
 514 {
 515     if ( xx )
 516         *xx = x - m_xScrollPosition * m_xScrollPixelsPerLine;
 517     if ( yy )
 518         *yy = y - m_yScrollPosition * m_yScrollPixelsPerLine;
 519 }
 520
 521 void wxScrolledWindow::CalcUnscrolledPosition(int x, int y, int *xx, int *yy) const
 522 {
 523     if ( xx )
 524         *xx = x + m_xScrollPosition * m_xScrollPixelsPerLine;
 525     if ( yy )
 526         *yy = y + m_yScrollPosition * m_yScrollPixelsPerLine;
 527 }
 528
 529 int wxScrolledWindow::CalcScrollInc(wxScrollWinEvent& event)
 530 {
 531     int pos = event.GetPosition();
 532     int orient = event.GetOrientation();
 533
 534     int nScrollInc = 0;
 535     if (event.GetEventType() == wxEVT_SCROLLWIN_TOP)
 536     {
 537             if (orient == wxHORIZONTAL)
 538                 nScrollInc = - m_xScrollPosition;
 539             else
 540                 nScrollInc = - m_yScrollPosition;
 541     } else
 542     if (event.GetEventType() == wxEVT_SCROLLWIN_BOTTOM)
 543     {
 544             if (orient == wxHORIZONTAL)
 545                 nScrollInc = m_xScrollLines - m_xScrollPosition;
 546             else
 547                 nScrollInc = m_yScrollLines - m_yScrollPosition;
 548     } else
 549     if (event.GetEventType() == wxEVT_SCROLLWIN_LINEUP)
 550     {
 551             nScrollInc = -1;
 552     } else
 553     if (event.GetEventType() == wxEVT_SCROLLWIN_LINEDOWN)
 554     {
 555             nScrollInc = 1;
 556     } else
 557     if (event.GetEventType() == wxEVT_SCROLLWIN_PAGEUP)
 558     {
 559             if (orient == wxHORIZONTAL)
 560                 nScrollInc = -GetScrollPageSize(wxHORIZONTAL);
 561             else
 562                 nScrollInc = -GetScrollPageSize(wxVERTICAL);
 563     } else
 564     if (event.GetEventType() == wxEVT_SCROLLWIN_PAGEDOWN)
 565     {
 566             if (orient == wxHORIZONTAL)
 567                 nScrollInc = GetScrollPageSize(wxHORIZONTAL);
 568             else
 569                 nScrollInc = GetScrollPageSize(wxVERTICAL);
 570     } else
 571     if ((event.GetEventType() == wxEVT_SCROLLWIN_THUMBTRACK) ||
 572         (event.GetEventType() == wxEVT_SCROLLWIN_THUMBRELEASE))
 573     {
 574             if (orient == wxHORIZONTAL)
 575                 nScrollInc = pos - m_xScrollPosition;
 576             else
 577                 nScrollInc = pos - m_yScrollPosition;
 578     }
 579
 580     if (orient == wxHORIZONTAL)
 581     {
 582         if (m_xScrollPixelsPerLine > 0)
 583         {
 584             int max = (int)(m_hAdjust->upper - m_hAdjust->page_size + 0.5);
 585             if (max < 0) max = 0;
 586
 587             if ( (m_xScrollPosition + nScrollInc) < 0 )
 588                 nScrollInc = -m_xScrollPosition; // As -ve as we can go
 589             else if ( (m_xScrollPosition + nScrollInc) > max )
 590                 nScrollInc = max - m_xScrollPosition; // As +ve as we can go
 591         }
 592         else
 593             m_targetWindow->Refresh();
 594     }
 595     else
 596     {
 597         if (m_yScrollPixelsPerLine > 0)
 598         {
 599             int max = (int)(m_vAdjust->upper - m_vAdjust->page_size + 0.5);
 600             if (max < 0) max = 0;
 601
 602             if ( (m_yScrollPosition + nScrollInc) < 0 )
 603                 nScrollInc = -m_yScrollPosition; // As -ve as we can go
 604             else if ( (m_yScrollPosition + nScrollInc) > max )
 605                 nScrollInc = max - m_yScrollPosition; // As +ve as we can go
 606         }
 607         else
 608             m_targetWindow->Refresh();
 609     }
 610
 611     return nScrollInc;
 612 }
 613
 614 void wxScrolledWindow::SetScrollPos( int orient, int pos, bool WXUNUSED(refresh) )
 615 {
 616     wxCHECK_RET( m_widget != NULL, wxT("invalid window") );
 617
 618     wxCHECK_RET( m_wxwindow != NULL, wxT("window needs client area for scrolling") );
 619
 620     if (orient == wxHORIZONTAL)
 621     {
 622         int max = (int)(m_hAdjust->upper - m_hAdjust->page_size + 0.5);
 623         if (max < 0) max = 0;
 624
 625         if (pos > max) pos = 0;
 626         if (pos < 0) pos = 0;
 627
 628         if (pos == (int)(m_hAdjust->value+0.5)) return;
 629         m_hAdjust->value = pos;
 630     }
 631     else
 632     {
 633         int max = (int)(m_vAdjust->upper - m_vAdjust->page_size + 0.5);
 634         if (max < 0) max = 0;
 635
 636         if (pos > max) pos = 0;
 637         if (pos < 0) pos = 0;
 638
 639         if (pos == (int)(m_vAdjust->value+0.5)) return;
 640         m_vAdjust->value = pos;
 641     }
 642
 643     if (m_wxwindow->window)
 644     {
 645         if (orient == wxHORIZONTAL)
 646         {
 647             // Just update the scrollbar, don't send any wxWindows event
 648             GtkHDisconnectEvent();
 649             gtk_signal_emit_by_name( GTK_OBJECT(m_hAdjust), "value_changed" );
 650             GtkHConnectEvent();
 651         }
 652         else
 653         {
 654             // Just update the scrollbar, don't send any wxWindows event
 655             GtkVDisconnectEvent();
 656             gtk_signal_emit_by_name( GTK_OBJECT(m_vAdjust), "value_changed" );
 657             GtkVConnectEvent();
 658         }
 659     }
 660 }
 661
 662 void wxScrolledWindow::GtkVConnectEvent()
 663 {
 664     gtk_signal_connect( GTK_OBJECT(m_vAdjust), "value_changed",
 665           (GtkSignalFunc) gtk_scrolled_window_vscroll_callback, (gpointer) this );
 666 }
 667
 668 void wxScrolledWindow::GtkHConnectEvent()
 669 {
 670     gtk_signal_connect( GTK_OBJECT(m_hAdjust), "value_changed",
 671           (GtkSignalFunc) gtk_scrolled_window_hscroll_callback, (gpointer) this );
 672 }
 673
 674 void wxScrolledWindow::GtkHDisconnectEvent()
 675 {
 676     gtk_signal_disconnect_by_func( GTK_OBJECT(m_hAdjust),
 677         (GtkSignalFunc) gtk_scrolled_window_hscroll_callback, (gpointer) this );
 678 }
 679
 680 void wxScrolledWindow::GtkVDisconnectEvent()
 681 {
 682     gtk_signal_disconnect_by_func( GTK_OBJECT(m_vAdjust),
 683         (GtkSignalFunc) gtk_scrolled_window_vscroll_callback, (gpointer) this );
 684 }
 685
 686 // ----------------------------------------------------------------------------
 687 // event handlers
 688 // ----------------------------------------------------------------------------
 689
 690 // Default OnSize resets scrollbars, if any
 691 void wxScrolledWindow::OnSize(wxSizeEvent& WXUNUSED(event))
 692 {
 693 #if wxUSE_CONSTRAINTS
 694     if (GetAutoLayout())
 695         Layout();
 696 #endif
 697
 698     AdjustScrollbars();
 699 }
 700
 701 // This calls OnDraw, having adjusted the origin according to the current
 702 // scroll position
 703 void wxScrolledWindow::OnPaint(wxPaintEvent& WXUNUSED(event))
 704 {
 705     wxPaintDC dc(this);
 706     PrepareDC(dc);
 707
 708     OnDraw(dc);
 709 }
 710
 711 // kbd handling: notice that we use OnChar() and not OnKeyDown() for
 712 // compatibility here - if we used OnKeyDown(), the programs which process
 713 // arrows themselves in their OnChar() would never get the message and like
 714 // this they always have the priority
 715 void wxScrolledWindow::OnChar(wxKeyEvent& event)
 716 {
 717     int stx, sty,       // view origin
 718         szx, szy,       // view size (total)
 719         clix, cliy;     // view size (on screen)
 720
 721     ViewStart(&stx, &sty);
 722     GetClientSize(&clix, &cliy);
 723     GetVirtualSize(&szx, &szy);
 724
 725     if( m_xScrollPixelsPerLine )
 726     {
 727         clix /= m_xScrollPixelsPerLine;
 728         szx /= m_xScrollPixelsPerLine;
 729     }
 730     else
 731     {
 732         clix = 0;
 733         szx = -1;
 734     }
 735     if( m_yScrollPixelsPerLine )
 736     {
 737         cliy /= m_yScrollPixelsPerLine;
 738         szy /= m_yScrollPixelsPerLine;
 739     }
 740     else
 741     {
 742         cliy = 0;
 743         szy = -1;
 744     }
 745
 746     int xScrollOld = GetScrollPos(wxHORIZONTAL),
 747         yScrollOld = GetScrollPos(wxVERTICAL);
 748
 749     int dsty;
 750     switch ( event.KeyCode() )
 751     {
 752         case WXK_PAGEUP:
 753         case WXK_PRIOR:
 754             dsty = sty - (5 * cliy / 6);
 755             Scroll(-1, (dsty == -1) ? 0 : dsty);
 756             break;
 757
 758         case WXK_PAGEDOWN:
 759         case WXK_NEXT:
 760             Scroll(-1, sty + (5 * cliy / 6));
 761             break;
 762
 763         case WXK_HOME:
 764             Scroll(0, event.ControlDown() ? 0 : -1);
 765             break;
 766
 767         case WXK_END:
 768             Scroll(szx - clix, event.ControlDown() ? szy - cliy : -1);
 769             break;
 770
 771         case WXK_UP:
 772             Scroll(-1, sty - 1);
 773             break;
 774
 775         case WXK_DOWN:
 776             Scroll(-1, sty + 1);
 777             break;
 778
 779         case WXK_LEFT:
 780             Scroll(stx - 1, -1);
 781             break;
 782
 783         case WXK_RIGHT:
 784             Scroll(stx + 1, -1);
 785             break;
 786
 787         default:
 788             // not for us
 789             event.Skip();
 790             return;
 791     }
 792
 793     int xScroll = GetScrollPos(wxHORIZONTAL);
 794     if ( xScroll != xScrollOld )
 795     {
 796         wxScrollWinEvent event(wxEVT_SCROLLWIN_THUMBTRACK, xScroll,
 797                                wxHORIZONTAL);
 798         event.SetEventObject(this);
 799         GetEventHandler()->ProcessEvent(event);
 800     }
 801
 802     int yScroll = GetScrollPos(wxVERTICAL);
 803     if ( yScroll != yScrollOld )
 804     {
 805         wxScrollWinEvent event(wxEVT_SCROLLWIN_THUMBTRACK, yScroll,
 806                                wxVERTICAL);
 807         event.SetEventObject(this);
 808         GetEventHandler()->ProcessEvent(event);
 809     }
 810 }
 811