src/gtk/scrolwin.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/gtk/scrolwin.cpp
   3 // Purpose:     wxScrolledWindow implementation
   4 // Author:      Robert Roebling
   5 // Modified by: Ron Lee
   6 //              Vadim Zeitlin: removed 90% of duplicated common code
   7 // Created:     01/02/97
   8 // RCS-ID:      $Id$
   9 // Copyright:   (c) Robert Roebling
  10 // Licence:     wxWindows licence
  11 /////////////////////////////////////////////////////////////////////////////
  12
  13 // For compilers that support precompilation, includes "wx.h".
  14 #include "wx/wxprec.h"
  15
  16 #ifdef __BORLANDC__
  17     #pragma hdrstop
  18 #endif
  19
  20 #include "wx/scrolwin.h"
  21
  22 #include <gtk/gtk.h>
  23 #include "wx/gtk/private/gtk2-compat.h"
  24
  25 // ----------------------------------------------------------------------------
  26 // wxScrollHelper implementation
  27 // ----------------------------------------------------------------------------
  28
  29 void wxScrollHelper::SetScrollbars(int pixelsPerUnitX, int pixelsPerUnitY,
  30                                    int noUnitsX, int noUnitsY,
  31                                    int xPos, int yPos,
  32                                    bool noRefresh)
  33 {
  34     base_type::SetScrollbars(
  35         pixelsPerUnitX, pixelsPerUnitY, noUnitsX, noUnitsY, xPos, yPos, noRefresh);
  36
  37     gtk_range_set_value(m_win->m_scrollBar[wxWindow::ScrollDir_Horz], m_xScrollPosition);
  38     gtk_range_set_value(m_win->m_scrollBar[wxWindow::ScrollDir_Vert], m_yScrollPosition);
  39     m_win->m_scrollPos[wxWindow::ScrollDir_Horz] =
  40         gtk_range_get_value(m_win->m_scrollBar[wxWindow::ScrollDir_Horz]);
  41     m_win->m_scrollPos[wxWindow::ScrollDir_Vert] =
  42         gtk_range_get_value(m_win->m_scrollBar[wxWindow::ScrollDir_Vert]);
  43 }
  44
  45 void wxScrollHelper::DoAdjustScrollbar(GtkRange* range,
  46                                        int pixelsPerLine,
  47                                        int winSize,
  48                                        int virtSize,
  49                                        int *pos,
  50                                        int *lines,
  51                                        int *linesPerPage)
  52 {
  53     if (!range)
  54         return;
  55
  56     int upper;
  57     int page_size;
  58     if (pixelsPerLine > 0 && winSize > 0 && winSize < virtSize)
  59     {
  60         upper = (virtSize + pixelsPerLine - 1) / pixelsPerLine;
  61         page_size = winSize / pixelsPerLine;
  62         *lines = upper;
  63         *linesPerPage = page_size;
  64     }
  65     else
  66     {
  67         // GtkRange won't allow upper == lower, so for disabled state use [0,1]
  68         //   with a page size of 1. This will also clamp position to 0.
  69         upper = 1;
  70         page_size = 1;
  71         *lines = 0;
  72         *linesPerPage = 0;
  73     }
  74
  75     gtk_range_set_increments(range, 1, page_size);
  76     gtk_adjustment_set_page_size(gtk_range_get_adjustment(range), page_size);
  77     gtk_range_set_range(range, 0, upper);
  78
  79     // ensure that the scroll position is always in valid range
  80     if (*pos > *lines)
  81         *pos = *lines;
  82 }
  83
  84 void wxScrollHelper::AdjustScrollbars()
  85 {
  86     int vw, vh;
  87     m_targetWindow->GetVirtualSize(&vw, &vh);
  88
  89     int w, h;
  90     const wxSize availSize = GetSizeAvailableForScrollTarget(
  91         m_win->GetSize() - m_win->GetWindowBorderSize());
  92     if ( availSize.x >= vw && availSize.y >= vh )
  93     {
  94         w = availSize.x;
  95         h = availSize.y;
  96
  97         // we know that the scrollbars will be removed
  98         DoAdjustHScrollbar(w, vw);
  99         DoAdjustVScrollbar(h, vh);
 100
 101         return;
 102     }
 103
 104     m_targetWindow->GetClientSize(&w, NULL);
 105     DoAdjustHScrollbar(w, vw);
 106
 107     m_targetWindow->GetClientSize(NULL, &h);
 108     DoAdjustVScrollbar(h, vh);
 109
 110     const int w_old = w;
 111     m_targetWindow->GetClientSize(&w, NULL);
 112     if ( w != w_old )
 113     {
 114         // It is necessary to repeat the calculations in this case to avoid an
 115         // observed infinite series of size events, involving alternating
 116         // changes in visibility of the scrollbars.
 117         // At this point, GTK+ has already queued a resize, which will cause
 118         // AdjustScrollbars() to be called again. If the scrollbar visibility
 119         // is not correct before then, yet another resize will occur, possibly
 120         // leading to an unending series if the sizes are just right.
 121         DoAdjustHScrollbar(w, vw);
 122
 123         m_targetWindow->GetClientSize(NULL, &h);
 124         DoAdjustVScrollbar(h, vh);
 125     }
 126 }
 127
 128 void wxScrollHelper::DoScrollOneDir(int orient,
 129                                     int pos,
 130                                     int pixelsPerLine,
 131                                     int *posOld)
 132 {
 133     if ( pos != -1 && pos != *posOld && pixelsPerLine )
 134     {
 135         m_win->SetScrollPos(orient, pos);
 136         pos = m_win->GetScrollPos(orient);
 137
 138         int diff = (*posOld - pos)*pixelsPerLine;
 139         m_targetWindow->ScrollWindow(orient == wxHORIZONTAL ? diff : 0,
 140                                      orient == wxHORIZONTAL ? 0 : diff);
 141
 142         *posOld = pos;
 143     }
 144 }
 145
 146 void wxScrollHelper::DoScroll( int x_pos, int y_pos )
 147 {
 148     wxCHECK_RET( m_targetWindow != 0, wxT("No target window") );
 149
 150     DoScrollOneDir(wxHORIZONTAL, x_pos, m_xScrollPixelsPerLine, &m_xScrollPosition);
 151     DoScrollOneDir(wxVERTICAL, y_pos, m_yScrollPixelsPerLine, &m_yScrollPosition);
 152 }
 153
 154 // ----------------------------------------------------------------------------
 155 // scrollbars visibility
 156 // ----------------------------------------------------------------------------
 157
 158 namespace
 159 {
 160
 161 GtkPolicyType GtkPolicyFromWX(wxScrollbarVisibility visibility)
 162 {
 163     GtkPolicyType policy;
 164     switch ( visibility )
 165     {
 166         case wxSHOW_SB_NEVER:
 167             policy = GTK_POLICY_NEVER;
 168             break;
 169
 170         case wxSHOW_SB_DEFAULT:
 171             policy = GTK_POLICY_AUTOMATIC;
 172             break;
 173
 174         default:
 175             wxFAIL_MSG( wxS("unknown scrollbar visibility") );
 176             // fall through
 177
 178         case wxSHOW_SB_ALWAYS:
 179             policy = GTK_POLICY_ALWAYS;
 180             break;
 181     }
 182
 183     return policy;
 184 }
 185
 186 } // anonymous namespace
 187
 188 void wxScrollHelper::DoShowScrollbars(wxScrollbarVisibility horz,
 189                                       wxScrollbarVisibility vert)
 190 {
 191     GtkScrolledWindow * const scrolled = GTK_SCROLLED_WINDOW(m_win->m_widget);
 192     wxCHECK_RET( scrolled, "window must be created" );
 193
 194     gtk_scrolled_window_set_policy(scrolled,
 195                                    GtkPolicyFromWX(horz),
 196                                    GtkPolicyFromWX(vert));
 197 }