// headers
// ----------------------------------------------------------------------------
+#if defined(__GNUG__) && !defined(__APPLE__)
+#pragma implementation "vscroll.h"
+#endif
+
+// For compilers that support precompilation, includes "wx.h".
+#include "wx/wxprec.h"
+
+#ifdef __BORLANDC__
+#pragma hdrstop
+#endif
+
#include "wx/vscroll.h"
// ----------------------------------------------------------------------------
// various helpers
// ----------------------------------------------------------------------------
+wxCoord wxVScrolledWindow::EstimateTotalHeight() const
+{
+ // estimate the total height: it is impossible to call
+ // OnGetLineHeight() for every line because there may be too many of
+ // them, so we just make a guess using some lines in the beginning,
+ // some in the end and some in the middle
+ static const size_t NUM_LINES_TO_SAMPLE = 10;
+
+ wxCoord heightTotal;
+ if ( m_lineMax < 3*NUM_LINES_TO_SAMPLE )
+ {
+ // in this case calculating exactly is faster and more correct than
+ // guessing
+ heightTotal = GetLinesHeight(0, m_lineMax);
+ }
+ else // too many lines to calculate exactly
+ {
+ // look at some lines in the beginning/middle/end
+ heightTotal =
+ GetLinesHeight(0, NUM_LINES_TO_SAMPLE) +
+ GetLinesHeight(m_lineMax - NUM_LINES_TO_SAMPLE, m_lineMax) +
+ GetLinesHeight(m_lineMax/2 - NUM_LINES_TO_SAMPLE/2,
+ m_lineMax/2 + NUM_LINES_TO_SAMPLE/2);
+
+ // use the height of the lines we looked as the average
+ heightTotal = (wxCoord)
+ (((float)m_heightTotal / (3*NUM_LINES_TO_SAMPLE)) * m_lineMax);
+ }
+
+ return heightTotal;
+}
+
wxCoord wxVScrolledWindow::GetLinesHeight(size_t lineMin, size_t lineMax) const
{
if ( lineMin == lineMax )
// save the number of lines
m_lineMax = count;
-
- // estimate the total height: it is impossible to call
- // OnGetLineHeight() for every line because there may be too many of
- // them, so we just make a guess using some lines in the beginning,
- // some in the end and some in the middle
- static const size_t NUM_LINES_TO_SAMPLE = 10;
-
- if ( count < 3*NUM_LINES_TO_SAMPLE )
- {
- // in this case calculating exactly is faster and more correct than
- // guessing
- m_heightTotal = GetLinesHeight(0, m_lineMax);
- }
- else // too many lines to calculate exactly
- {
- // look at some lines in the beginning/middle/end
- m_heightTotal =
- GetLinesHeight(0, NUM_LINES_TO_SAMPLE) +
- GetLinesHeight(count - NUM_LINES_TO_SAMPLE, count) +
- GetLinesHeight(count/2 - NUM_LINES_TO_SAMPLE/2,
- count/2 + NUM_LINES_TO_SAMPLE/2);
-
- // use the height of the lines we looked as the average
- m_heightTotal = (wxCoord)
- (((float)m_heightTotal / (3*NUM_LINES_TO_SAMPLE)) * m_lineMax);
- }
-
+ // and our estimate for their total height
+ m_heightTotal = EstimateTotalHeight();
// recalculate the scrollbars parameters
m_lineFirst = 1; // make sure it is != 0