Aren/haiku
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

According to my tests on R5, a BScrollBar with a proportion of 0.0, the value

Browse Source 
that it has when you never set it, uses the large step to figure out the
proportion it should display. This fixes Pe's scroll bars to display the
"correct" proportion. Of course the proportion is only correct if the large
step indeed equals the page size. Fixes #1758.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@24838 a95241bf-73f2-0310-859d-f6bbb57e9c96
This commit is contained in:
Stephan Aßmus 2008-04-06 16:47:43 +00:00
parent a43222b925
commit 1158eeac58
1 changed files with 36 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

45
src/kits/interface/ScrollBar.cpp
View File

@ -21,7 +21,7 @@
#include <stdlib.h>
#include <string.h>
//#define TRACE_SCROLLBAR
#define TRACE_SCROLLBAR
#ifdef TRACE_SCROLLBAR
# define TRACE(x...) printf(x)
#else
@ -445,15 +445,33 @@ BScrollBar::GetRange(float *min, float *max) const
void
BScrollBar::SetSteps(float smallStep, float largeStep)
{
// Under R5, steps can be set only after being attached to a window, probably because
// the data is kept server-side. We'll just remove that limitation... :P
TRACE("BScrollBar(%s)::SetSteps(small=%.1f, large=%.1f)\n", Name(),
smallStep, largeStep);
// The BeBook also says that we need to specify an integer value even though the step
// values are floats. For the moment, we'll just make sure that they are integers
fSmallStep = roundf(smallStep);
fLargeStep = roundf(largeStep);
// Under R5, steps can be set only after being attached to a window,
// probably because the data is kept server-side. We'll just remove
// that limitation... :P
// TODO: test use of fractional values and make them work properly if they don't
// The BeBook also says that we need to specify an integer value even
// though the step values are floats. For the moment, we'll just make
// sure that they are integers
smallStep = roundf(smallStep);
largeStep = roundf(largeStep);
if (fSmallStep == smallStep && fLargeStep == largeStep)
return;
fSmallStep = smallStep;
fLargeStep = largeStep;
if (fProportion == 0.0) {
// special case, proportion is based on fLargeStep if it was never
// set, so it means we need to invalidate here
_UpdateThumbFrame();
Invalidate();
}
// TODO: test use of fractional values and make them work properly if
// they don't
}
// GetSteps
@ -1123,8 +1141,17 @@ BScrollBar::_UpdateThumbFrame()
float thumbSize = minSize;
float proportion = fProportion;
if (fMin == fMax || proportion > 1.0 || proportion < 0.0)
if (fMin >= fMax || proportion > 1.0 || proportion < 0.0)
proportion = 1.0;
if (proportion == 0.0) {
// Special case a proportion of 0.0, use the large step value
// in that case (NOTE: fMin == fMax already handled above)
// This calculation is based on the assumption that "large step"
// scrolls by one "page size".
proportion = fLargeStep / (2 * (fMax - fMin));
if (proportion > 1.0)
proportion = 1.0;
}
if (fPrivateData->fScrollBarInfo.proportional)
thumbSize += (maxSize - minSize) * proportion;
thumbSize = floorf(thumbSize + 0.5);