src/msw/scrolbar.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/msw/scrolbar.cpp
   3 // Purpose:     wxScrollBar
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     04/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Julian Smart
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // For compilers that support precompilation, includes "wx.h".
  13 #include "wx/wxprec.h"
  14
  15 #ifdef __BORLANDC__
  16     #pragma hdrstop
  17 #endif
  18
  19 #if wxUSE_SCROLLBAR
  20
  21 #include "wx/scrolbar.h"
  22
  23 #ifndef WX_PRECOMP
  24     #include "wx/utils.h"
  25     #include "wx/settings.h"
  26 #endif
  27
  28 #include "wx/msw/private.h"
  29
  30 // Scrollbar
  31 bool wxScrollBar::Create(wxWindow *parent, wxWindowID id,
  32            const wxPoint& pos,
  33            const wxSize& size, long style,
  34            const wxValidator& validator,
  35            const wxString& name)
  36 {
  37     if ( !CreateControl(parent, id, pos, size, style, validator, name) )
  38         return false;
  39
  40     if (!MSWCreateControl(wxT("ScrollBar"), wxEmptyString, pos, size))
  41         return false;
  42
  43     SetScrollbar(0, 1, 2, 1, false);
  44
  45     return true;
  46 }
  47
  48 wxScrollBar::~wxScrollBar(void)
  49 {
  50 }
  51
  52 bool wxScrollBar::MSWOnScroll(int WXUNUSED(orientation), WXWORD wParam,
  53                               WXWORD WXUNUSED(pos), WXHWND WXUNUSED(control))
  54 {
  55     // don't use pos parameter because it is limited to 16 bits, get the full
  56     // 32 bit position from the control itself instead
  57     WinStruct<SCROLLINFO> scrollInfo;
  58     scrollInfo.fMask = SIF_RANGE | SIF_POS | SIF_TRACKPOS;
  59
  60     if ( !::GetScrollInfo(GetHwnd(), SB_CTL, &scrollInfo) )
  61     {
  62         wxLogLastError(wxT("GetScrollInfo"));
  63         return false;
  64     }
  65
  66     int maxPos = scrollInfo.nMax;
  67
  68     // A page size greater than one has the effect of reducing the effective
  69     // range, therefore the range has already been boosted artificially - so
  70     // reduce it again.
  71     if ( m_pageSize > 1 )
  72         maxPos -= (m_pageSize - 1);
  73
  74     int position = scrollInfo.nPos;
  75     wxEventType scrollEvent = wxEVT_NULL;
  76     switch ( wParam )
  77     {
  78         case SB_TOP:
  79             position = 0;
  80             scrollEvent = wxEVT_SCROLL_TOP;
  81             break;
  82
  83         case SB_BOTTOM:
  84             position = maxPos;
  85             scrollEvent = wxEVT_SCROLL_BOTTOM;
  86             break;
  87
  88         case SB_LINEUP:
  89             position--;
  90             scrollEvent = wxEVT_SCROLL_LINEUP;
  91             break;
  92
  93         case SB_LINEDOWN:
  94             position++;
  95             scrollEvent = wxEVT_SCROLL_LINEDOWN;
  96             break;
  97
  98         case SB_PAGEUP:
  99             position -= GetPageSize();
 100             scrollEvent = wxEVT_SCROLL_PAGEUP;
 101             break;
 102
 103         case SB_PAGEDOWN:
 104             position += GetPageSize();
 105             scrollEvent = wxEVT_SCROLL_PAGEDOWN;
 106             break;
 107
 108         case SB_THUMBPOSITION:
 109         case SB_THUMBTRACK:
 110             position = scrollInfo.nTrackPos;
 111             scrollEvent = wParam == SB_THUMBPOSITION ? wxEVT_SCROLL_THUMBRELEASE
 112                                                      : wxEVT_SCROLL_THUMBTRACK;
 113             break;
 114
 115         case SB_ENDSCROLL:
 116             scrollEvent = wxEVT_SCROLL_CHANGED;
 117             break;
 118     }
 119
 120     if ( position != scrollInfo.nPos )
 121     {
 122         if ( position < 0 )
 123             position = 0;
 124         if ( position > maxPos )
 125             position = maxPos;
 126
 127         SetThumbPosition(position);
 128     }
 129     else if ( scrollEvent != wxEVT_SCROLL_THUMBRELEASE &&
 130                 scrollEvent != wxEVT_SCROLL_CHANGED )
 131     {
 132         // don't process the event if there is no displacement,
 133         // unless this is a thumb release or end scroll event.
 134         return false;
 135     }
 136
 137     wxScrollEvent event(scrollEvent, m_windowId);
 138     event.SetOrientation(IsVertical() ? wxVERTICAL : wxHORIZONTAL);
 139     event.SetPosition(position);
 140     event.SetEventObject( this );
 141
 142     return HandleWindowEvent(event);
 143 }
 144
 145 void wxScrollBar::SetThumbPosition(int viewStart)
 146 {
 147     SCROLLINFO info;
 148     info.cbSize = sizeof(SCROLLINFO);
 149     info.nPage = 0;
 150     info.nMin = 0;
 151     info.nPos = viewStart;
 152     info.fMask = SIF_POS ;
 153
 154     ::SetScrollInfo((HWND) GetHWND(), SB_CTL, &info, TRUE);
 155 }
 156
 157 int wxScrollBar::GetThumbPosition(void) const
 158 {
 159     WinStruct<SCROLLINFO> scrollInfo;
 160     scrollInfo.fMask = SIF_POS;
 161
 162     if ( !::GetScrollInfo(GetHwnd(), SB_CTL, &scrollInfo) )
 163     {
 164         wxLogLastError(wxT("GetScrollInfo"));
 165     }
 166     return scrollInfo.nPos;
 167 }
 168
 169 void wxScrollBar::SetScrollbar(int position, int thumbSize, int range, int pageSize,
 170     bool refresh)
 171 {
 172     m_viewSize = pageSize;
 173     m_pageSize = thumbSize;
 174     m_objectSize = range;
 175
 176     // The range (number of scroll steps) is the
 177     // object length minus the page size.
 178     int range1 = wxMax((m_objectSize - m_pageSize), 0) ;
 179
 180     // Try to adjust the range to cope with page size > 1
 181     // (see comment for SetPageLength)
 182     if ( m_pageSize > 1 )
 183     {
 184         range1 += (m_pageSize - 1);
 185     }
 186
 187     SCROLLINFO info;
 188     info.cbSize = sizeof(SCROLLINFO);
 189     info.nPage = m_pageSize;
 190     info.nMin = 0;
 191     info.nMax = range1;
 192     info.nPos = position;
 193
 194     info.fMask = SIF_PAGE | SIF_RANGE | SIF_POS;
 195
 196     ::SetScrollInfo((HWND) GetHWND(), SB_CTL, &info, refresh);
 197 }
 198
 199 void wxScrollBar::Command(wxCommandEvent& event)
 200 {
 201     SetThumbPosition(event.GetInt());
 202     ProcessCommand(event);
 203 }
 204
 205 wxSize wxScrollBar::DoGetBestSize() const
 206 {
 207     int w = 100;
 208     int h = 100;
 209
 210     if ( IsVertical() )
 211     {
 212         w = wxSystemSettings::GetMetric(wxSYS_VSCROLL_X);
 213     }
 214     else
 215     {
 216         h = wxSystemSettings::GetMetric(wxSYS_HSCROLL_Y);
 217     }
 218
 219     wxSize best(w, h);
 220     CacheBestSize(best);
 221     return best;
 222 }
 223
 224 WXDWORD wxScrollBar::MSWGetStyle(long style, WXDWORD *exstyle) const
 225 {
 226     // we never have an external border
 227     WXDWORD msStyle = wxControl::MSWGetStyle
 228                       (
 229                         (style & ~wxBORDER_MASK) | wxBORDER_NONE, exstyle
 230                       );
 231
 232     // SBS_HORZ is 0 anyhow, but do mention it explicitly for clarity
 233     msStyle |= style & wxSB_HORIZONTAL ? SBS_HORZ : SBS_VERT;
 234
 235     return msStyle;
 236 }
 237
 238 WXHBRUSH wxScrollBar::MSWControlColor(WXHDC pDC, WXHWND hWnd)
 239 {
 240     // unless we have an explicitly set bg colour, use default (gradient under
 241     // XP) brush instead of GetBackgroundColour() one as the base class would
 242     //
 243     // note that fg colour isn't used for a scrollbar
 244     return UseBgCol() ? wxControl::MSWControlColor(pDC, hWnd) : NULL;
 245 }
 246
 247 #endif // wxUSE_SCROLLBAR