src/gtk/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     m_xScrollPixelsPerLine = pixelsPerUnitX;
 245     m_yScrollPixelsPerLine = pixelsPerUnitY;
 246     m_xScrollPosition = xPos;
 247     m_yScrollPosition = yPos;
 248     m_xScrollLines = noUnitsX;
 249     m_yScrollLines = noUnitsY;
 250
 251     m_hAdjust->lower = 0.0;
 252     m_hAdjust->upper = noUnitsX;
 253     m_hAdjust->value = xPos;
 254     m_hAdjust->step_increment = 1.0;
 255     m_hAdjust->page_increment = 2.0;
 256
 257     m_vAdjust->lower = 0.0;
 258     m_vAdjust->upper = noUnitsY;
 259     m_vAdjust->value = yPos;
 260     m_vAdjust->step_increment = 1.0;
 261     m_vAdjust->page_increment = 2.0;
 262
 263     AdjustScrollbars();
 264 }
 265
 266 void wxScrolledWindow::AdjustScrollbars()
 267 {
 268     int w, h;
 269     m_targetWindow->GetClientSize( &w, &h );
 270
 271     if (m_xScrollPixelsPerLine == 0)
 272         m_hAdjust->page_size = 1.0;
 273     else
 274         m_hAdjust->page_size = (w / m_xScrollPixelsPerLine);
 275
 276     if (m_yScrollPixelsPerLine == 0)
 277         m_vAdjust->page_size = 1.0;
 278     else
 279         m_vAdjust->page_size = (h / m_yScrollPixelsPerLine);
 280
 281     m_xScrollLinesPerPage = (int)(m_hAdjust->page_size + 0.5);
 282     m_yScrollLinesPerPage = (int)(m_vAdjust->page_size + 0.5);
 283
 284     gtk_signal_emit_by_name( GTK_OBJECT(m_vAdjust), "changed" );
 285     gtk_signal_emit_by_name( GTK_OBJECT(m_hAdjust), "changed" );
 286 }
 287
 288 // ----------------------------------------------------------------------------
 289 // target window handling
 290 // ----------------------------------------------------------------------------
 291
 292 void wxScrolledWindow::SetTargetWindow( wxWindow *target )
 293 {
 294     wxASSERT_MSG( target, wxT("target window must not be NULL") );
 295     m_targetWindow = target;
 296 }
 297
 298 wxWindow *wxScrolledWindow::GetTargetWindow()
 299 {
 300     return m_targetWindow;
 301 }
 302
 303 // Override this function if you don't want to have wxScrolledWindow
 304 // automatically change the origin according to the scroll position.
 305 void wxScrolledWindow::PrepareDC(wxDC& dc)
 306 {
 307     dc.SetDeviceOrigin( -m_xScrollPosition * m_xScrollPixelsPerLine,
 308                         -m_yScrollPosition * m_yScrollPixelsPerLine );
 309 }
 310
 311 void wxScrolledWindow::GetScrollPixelsPerUnit (int *x_unit, int *y_unit) const
 312 {
 313     if ( x_unit )
 314         *x_unit = m_xScrollPixelsPerLine;
 315     if ( y_unit )
 316         *y_unit = m_yScrollPixelsPerLine;
 317 }
 318
 319 int wxScrolledWindow::GetScrollPageSize(int orient) const
 320 {
 321     if ( orient == wxHORIZONTAL )
 322         return m_xScrollLinesPerPage;
 323     else
 324         return m_yScrollLinesPerPage;
 325 }
 326
 327 void wxScrolledWindow::SetScrollPageSize(int orient, int pageSize)
 328 {
 329     if ( orient == wxHORIZONTAL )
 330         m_xScrollLinesPerPage = pageSize;
 331     else
 332         m_yScrollLinesPerPage = pageSize;
 333 }
 334
 335 void wxScrolledWindow::OnScroll(wxScrollWinEvent& event)
 336 {
 337     int orient = event.GetOrientation();
 338
 339     int nScrollInc = CalcScrollInc(event);
 340     if (nScrollInc == 0) return;
 341
 342     if (orient == wxHORIZONTAL)
 343     {
 344         int newPos = m_xScrollPosition + nScrollInc;
 345         SetScrollPos(wxHORIZONTAL, newPos, TRUE );
 346     }
 347     else
 348     {
 349         int newPos = m_yScrollPosition + nScrollInc;
 350         SetScrollPos(wxVERTICAL, newPos, TRUE );
 351     }
 352
 353     if (orient == wxHORIZONTAL)
 354     {
 355         m_xScrollPosition += nScrollInc;
 356     }
 357     else
 358     {
 359         m_yScrollPosition += nScrollInc;
 360     }
 361
 362     if (orient == wxHORIZONTAL)
 363     {
 364        if (m_xScrollingEnabled)
 365             m_targetWindow->ScrollWindow(-m_xScrollPixelsPerLine * nScrollInc, 0, (const wxRect *) NULL);
 366        else
 367             m_targetWindow->Refresh();
 368     }
 369     else
 370     {
 371         if (m_yScrollingEnabled)
 372             m_targetWindow->ScrollWindow(0, -m_yScrollPixelsPerLine * nScrollInc, (const wxRect *) NULL);
 373         else
 374             m_targetWindow->Refresh();
 375     }
 376 }
 377
 378 void wxScrolledWindow::Scroll( int x_pos, int y_pos )
 379 {
 380     if (!m_targetWindow)
 381         return;
 382
 383     if (((x_pos == -1) || (x_pos == m_xScrollPosition)) &&
 384         ((y_pos == -1) || (y_pos == m_yScrollPosition))) return;
 385
 386     if ((x_pos != -1) && (m_xScrollPixelsPerLine))
 387     {
 388         int max = (int)(m_hAdjust->upper - m_hAdjust->page_size + 0.5);
 389         if (max < 0) max = 0;
 390         if (x_pos > max) x_pos = max;
 391         if (x_pos < 0) x_pos = 0;
 392
 393         int old_x = m_xScrollPosition;
 394         m_xScrollPosition = x_pos;
 395         m_hAdjust->value = x_pos;
 396
 397         m_targetWindow->ScrollWindow( (old_x-m_xScrollPosition)*m_xScrollPixelsPerLine, 0 );
 398
 399         // Just update the scrollbar, don't send any wxWindows event
 400         GtkHDisconnectEvent();
 401         gtk_signal_emit_by_name( GTK_OBJECT(m_hAdjust), "value_changed" );
 402         GtkHConnectEvent();
 403     }
 404
 405     if ((y_pos != -1) && (m_yScrollPixelsPerLine))
 406     {
 407         int max = (int)(m_vAdjust->upper - m_vAdjust->page_size + 0.5);
 408         if (max < 0) max = 0;
 409         if (y_pos > max) y_pos = max;
 410         if (y_pos < 0) y_pos = 0;
 411
 412         int old_y = m_yScrollPosition;
 413         m_yScrollPosition = y_pos;
 414         m_vAdjust->value = y_pos;
 415
 416         m_targetWindow->ScrollWindow( 0, (old_y-m_yScrollPosition)*m_yScrollPixelsPerLine );
 417
 418         // Just update the scrollbar, don't send any wxWindows event
 419         GtkVDisconnectEvent();
 420         gtk_signal_emit_by_name( GTK_OBJECT(m_vAdjust), "value_changed" );
 421         GtkVConnectEvent();
 422     }
 423 }
 424
 425 void wxScrolledWindow::GtkVScroll( float value )
 426 {
 427     if (!m_targetWindow)
 428         return;
 429
 430     if (m_yScrollPixelsPerLine == 0)
 431         return;
 432
 433     int y_pos = (int)(value+0.5);
 434
 435     if (y_pos == m_yScrollPosition)
 436         return;
 437
 438     GtkScrolledWindow *scrolledWindow = GTK_SCROLLED_WINDOW(m_widget);
 439     GtkRange *range = GTK_RANGE(scrolledWindow->vscrollbar);
 440
 441     wxEventType command = wxEVT_SCROLLWIN_THUMBTRACK;
 442     if      (range->scroll_type == GTK_SCROLL_STEP_BACKWARD) command = wxEVT_SCROLLWIN_LINEUP;
 443     else if (range->scroll_type == GTK_SCROLL_STEP_FORWARD)  command = wxEVT_SCROLLWIN_LINEDOWN;
 444     else if (range->scroll_type == GTK_SCROLL_PAGE_BACKWARD) command = wxEVT_SCROLLWIN_PAGEUP;
 445     else if (range->scroll_type == GTK_SCROLL_PAGE_FORWARD)  command = wxEVT_SCROLLWIN_PAGEDOWN;
 446
 447     wxScrollWinEvent event( command, y_pos, wxVERTICAL );
 448     event.SetEventObject( this );
 449     GetEventHandler()->ProcessEvent( event );
 450 }
 451
 452 void wxScrolledWindow::GtkHScroll( float value )
 453 {
 454     if (!m_targetWindow)
 455         return;
 456
 457     if (m_xScrollPixelsPerLine == 0)
 458         return;
 459
 460     int x_pos = (int)(value+0.5);
 461
 462     if (x_pos == m_xScrollPosition)
 463         return;
 464
 465     GtkScrolledWindow *scrolledWindow = GTK_SCROLLED_WINDOW(m_widget);
 466     GtkRange *range = GTK_RANGE(scrolledWindow->hscrollbar);
 467
 468     wxEventType command = wxEVT_SCROLLWIN_THUMBTRACK;
 469     if      (range->scroll_type == GTK_SCROLL_STEP_BACKWARD) command = wxEVT_SCROLLWIN_LINEUP;
 470     else if (range->scroll_type == GTK_SCROLL_STEP_FORWARD)  command = wxEVT_SCROLLWIN_LINEDOWN;
 471     else if (range->scroll_type == GTK_SCROLL_PAGE_BACKWARD) command = wxEVT_SCROLLWIN_PAGEUP;
 472     else if (range->scroll_type == GTK_SCROLL_PAGE_FORWARD)  command = wxEVT_SCROLLWIN_PAGEDOWN;
 473
 474     wxScrollWinEvent event( command, x_pos, wxHORIZONTAL );
 475     event.SetEventObject( this );
 476     GetEventHandler()->ProcessEvent( event );
 477 }
 478
 479 void wxScrolledWindow::EnableScrolling (bool x_scroll, bool y_scroll)
 480 {
 481     m_xScrollingEnabled = x_scroll;
 482     m_yScrollingEnabled = y_scroll;
 483 }
 484
 485 void wxScrolledWindow::GetVirtualSize (int *x, int *y) const
 486 {
 487     if ( x )
 488         *x = m_xScrollPixelsPerLine * m_xScrollLines;
 489     if ( y )
 490         *y = m_yScrollPixelsPerLine * m_yScrollLines;
 491 }
 492
 493 // Where the current view starts from
 494 void wxScrolledWindow::GetViewStart (int *x, int *y) const
 495 {
 496     if ( x )
 497         *x = m_xScrollPosition;
 498     if ( y )
 499         *y = m_yScrollPosition;
 500 }
 501
 502 void wxScrolledWindow::CalcScrolledPosition(int x, int y, int *xx, int *yy) const
 503 {
 504     if ( xx )
 505         *xx = x - m_xScrollPosition * m_xScrollPixelsPerLine;
 506     if ( yy )
 507         *yy = y - m_yScrollPosition * m_yScrollPixelsPerLine;
 508 }
 509
 510 void wxScrolledWindow::CalcUnscrolledPosition(int x, int y, int *xx, int *yy) const
 511 {
 512     if ( xx )
 513         *xx = x + m_xScrollPosition * m_xScrollPixelsPerLine;
 514     if ( yy )
 515         *yy = y + m_yScrollPosition * m_yScrollPixelsPerLine;
 516 }
 517
 518 int wxScrolledWindow::CalcScrollInc(wxScrollWinEvent& event)
 519 {
 520     int pos = event.GetPosition();
 521     int orient = event.GetOrientation();
 522
 523     int nScrollInc = 0;
 524     if (event.GetEventType() == wxEVT_SCROLLWIN_TOP)
 525     {
 526             if (orient == wxHORIZONTAL)
 527                 nScrollInc = - m_xScrollPosition;
 528             else
 529                 nScrollInc = - m_yScrollPosition;
 530     } else
 531     if (event.GetEventType() == wxEVT_SCROLLWIN_BOTTOM)
 532     {
 533             if (orient == wxHORIZONTAL)
 534                 nScrollInc = m_xScrollLines - m_xScrollPosition;
 535             else
 536                 nScrollInc = m_yScrollLines - m_yScrollPosition;
 537     } else
 538     if (event.GetEventType() == wxEVT_SCROLLWIN_LINEUP)
 539     {
 540             nScrollInc = -1;
 541     } else
 542     if (event.GetEventType() == wxEVT_SCROLLWIN_LINEDOWN)
 543     {
 544             nScrollInc = 1;
 545     } else
 546     if (event.GetEventType() == wxEVT_SCROLLWIN_PAGEUP)
 547     {
 548             if (orient == wxHORIZONTAL)
 549                 nScrollInc = -GetScrollPageSize(wxHORIZONTAL);
 550             else
 551                 nScrollInc = -GetScrollPageSize(wxVERTICAL);
 552     } else
 553     if (event.GetEventType() == wxEVT_SCROLLWIN_PAGEDOWN)
 554     {
 555             if (orient == wxHORIZONTAL)
 556                 nScrollInc = GetScrollPageSize(wxHORIZONTAL);
 557             else
 558                 nScrollInc = GetScrollPageSize(wxVERTICAL);
 559     } else
 560     if ((event.GetEventType() == wxEVT_SCROLLWIN_THUMBTRACK) ||
 561         (event.GetEventType() == wxEVT_SCROLLWIN_THUMBRELEASE))
 562     {
 563             if (orient == wxHORIZONTAL)
 564                 nScrollInc = pos - m_xScrollPosition;
 565             else
 566                 nScrollInc = pos - m_yScrollPosition;
 567     }
 568
 569     if (orient == wxHORIZONTAL)
 570     {
 571         if (m_xScrollPixelsPerLine > 0)
 572         {
 573             int max = (int)(m_hAdjust->upper - m_hAdjust->page_size + 0.5);
 574             if (max < 0) max = 0;
 575
 576             if ( (m_xScrollPosition + nScrollInc) < 0 )
 577                 nScrollInc = -m_xScrollPosition; // As -ve as we can go
 578             else if ( (m_xScrollPosition + nScrollInc) > max )
 579                 nScrollInc = max - m_xScrollPosition; // As +ve as we can go
 580         }
 581         else
 582             m_targetWindow->Refresh();
 583     }
 584     else
 585     {
 586         if (m_yScrollPixelsPerLine > 0)
 587         {
 588             int max = (int)(m_vAdjust->upper - m_vAdjust->page_size + 0.5);
 589             if (max < 0) max = 0;
 590
 591             if ( (m_yScrollPosition + nScrollInc) < 0 )
 592                 nScrollInc = -m_yScrollPosition; // As -ve as we can go
 593             else if ( (m_yScrollPosition + nScrollInc) > max )
 594                 nScrollInc = max - m_yScrollPosition; // As +ve as we can go
 595         }
 596         else
 597             m_targetWindow->Refresh();
 598     }
 599
 600     return nScrollInc;
 601 }
 602
 603 void wxScrolledWindow::SetScrollPos( int orient, int pos, bool WXUNUSED(refresh) )
 604 {
 605     wxCHECK_RET( m_widget != NULL, wxT("invalid window") );
 606
 607     wxCHECK_RET( m_wxwindow != NULL, wxT("window needs client area for scrolling") );
 608
 609     if (orient == wxHORIZONTAL)
 610     {
 611         int max = (int)(m_hAdjust->upper - m_hAdjust->page_size + 0.5);
 612         if (max < 0) max = 0;
 613
 614         if (pos > max) pos = 0;
 615         if (pos < 0) pos = 0;
 616
 617         if (pos == (int)(m_hAdjust->value+0.5)) return;
 618         m_hAdjust->value = pos;
 619     }
 620     else
 621     {
 622         int max = (int)(m_vAdjust->upper - m_vAdjust->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_vAdjust->value+0.5)) return;
 629         m_vAdjust->value = pos;
 630     }
 631
 632     if (m_wxwindow->window)
 633     {
 634         if (orient == wxHORIZONTAL)
 635         {
 636             // Just update the scrollbar, don't send any wxWindows event
 637             GtkHDisconnectEvent();
 638             gtk_signal_emit_by_name( GTK_OBJECT(m_hAdjust), "value_changed" );
 639             GtkHConnectEvent();
 640         }
 641         else
 642         {
 643             // Just update the scrollbar, don't send any wxWindows event
 644             GtkVDisconnectEvent();
 645             gtk_signal_emit_by_name( GTK_OBJECT(m_vAdjust), "value_changed" );
 646             GtkVConnectEvent();
 647         }
 648     }
 649 }
 650
 651 void wxScrolledWindow::GtkVConnectEvent()
 652 {
 653     gtk_signal_connect( GTK_OBJECT(m_vAdjust), "value_changed",
 654           (GtkSignalFunc) gtk_scrolled_window_vscroll_callback, (gpointer) this );
 655 }
 656
 657 void wxScrolledWindow::GtkHConnectEvent()
 658 {
 659     gtk_signal_connect( GTK_OBJECT(m_hAdjust), "value_changed",
 660           (GtkSignalFunc) gtk_scrolled_window_hscroll_callback, (gpointer) this );
 661 }
 662
 663 void wxScrolledWindow::GtkHDisconnectEvent()
 664 {
 665     gtk_signal_disconnect_by_func( GTK_OBJECT(m_hAdjust),
 666         (GtkSignalFunc) gtk_scrolled_window_hscroll_callback, (gpointer) this );
 667 }
 668
 669 void wxScrolledWindow::GtkVDisconnectEvent()
 670 {
 671     gtk_signal_disconnect_by_func( GTK_OBJECT(m_vAdjust),
 672         (GtkSignalFunc) gtk_scrolled_window_vscroll_callback, (gpointer) this );
 673 }
 674
 675 // ----------------------------------------------------------------------------
 676 // event handlers
 677 // ----------------------------------------------------------------------------
 678
 679 // Default OnSize resets scrollbars, if any
 680 void wxScrolledWindow::OnSize(wxSizeEvent& WXUNUSED(event))
 681 {
 682 #if wxUSE_CONSTRAINTS
 683     if (GetAutoLayout())
 684         Layout();
 685 #endif
 686
 687     AdjustScrollbars();
 688 }
 689
 690 // This calls OnDraw, having adjusted the origin according to the current
 691 // scroll position
 692 void wxScrolledWindow::OnPaint(wxPaintEvent& WXUNUSED(event))
 693 {
 694     wxPaintDC dc(this);
 695     PrepareDC(dc);
 696
 697     OnDraw(dc);
 698 }
 699
 700 // kbd handling: notice that we use OnChar() and not OnKeyDown() for
 701 // compatibility here - if we used OnKeyDown(), the programs which process
 702 // arrows themselves in their OnChar() would never get the message and like
 703 // this they always have the priority
 704 void wxScrolledWindow::OnChar(wxKeyEvent& event)
 705 {
 706     int stx, sty,       // view origin
 707         szx, szy,       // view size (total)
 708         clix, cliy;     // view size (on screen)
 709
 710     ViewStart(&stx, &sty);
 711     GetClientSize(&clix, &cliy);
 712     GetVirtualSize(&szx, &szy);
 713
 714     if( m_xScrollPixelsPerLine )
 715     {
 716         clix /= m_xScrollPixelsPerLine;
 717         szx /= m_xScrollPixelsPerLine;
 718     }
 719     else
 720     {
 721         clix = 0;
 722         szx = -1;
 723     }
 724     if( m_yScrollPixelsPerLine )
 725     {
 726         cliy /= m_yScrollPixelsPerLine;
 727         szy /= m_yScrollPixelsPerLine;
 728     }
 729     else
 730     {
 731         cliy = 0;
 732         szy = -1;
 733     }
 734
 735     int dsty;
 736     switch ( event.KeyCode() )
 737     {
 738         case WXK_PAGEUP:
 739         case WXK_PRIOR:
 740             dsty = sty - (5 * cliy / 6);
 741             Scroll(-1, (dsty == -1) ? 0 : dsty);
 742             break;
 743
 744         case WXK_PAGEDOWN:
 745         case WXK_NEXT:
 746             Scroll(-1, sty + (5 * cliy / 6));
 747             break;
 748
 749         case WXK_HOME:
 750             Scroll(0, event.ControlDown() ? 0 : -1);
 751             break;
 752
 753         case WXK_END:
 754             Scroll(szx - clix, event.ControlDown() ? szy - cliy : -1);
 755             break;
 756
 757         case WXK_UP:
 758             Scroll(-1, sty - 1);
 759             break;
 760
 761         case WXK_DOWN:
 762             Scroll(-1, sty + 1);
 763             break;
 764
 765         case WXK_LEFT:
 766             Scroll(stx - 1, -1);
 767             break;
 768
 769         case WXK_RIGHT:
 770             Scroll(stx + 1, -1);
 771             break;
 772
 773         default:
 774             // not for us
 775             event.Skip();
 776     }
 777 }
 778