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