The attached fixes two problems I noticed that were exposed with a small
display area for a grid:
1. A range check error if compiled with checks on
2. A hang on scrolling two a particular cell if it is not possible to
show all of the cell
Colin
diff -uNr lazarus/lcl/grids.pas /dos/fpc/lazarus.w/lcl/grids.pas
--- lazarus/lcl/grids.pas 2006-02-25 12:29:24.000000000 +0000
+++ /dos/fpc/lazarus.w/lcl/grids.pas 2006-03-04 12:53:48.000000000 +0000
@@ -2162,7 +2162,8 @@
{$endif}
ScrollInfo.nMin := 0;
ScrollInfo.nMax := ARange;
- ScrollInfo.nPage := APage;
+ if aPage > 0 then
+ ScrollInfo.nPage := APage;
SetScrollInfo(Handle, Which, ScrollInfo, True);
end;
end;
@@ -2308,19 +2309,21 @@
Xinc:=0;
if Rnew.Left + FGCache.TLColOff < FGCache.FixedWidth then Xinc:=-1
- else if RNew.Right + FGCache.TLColOff > FGCache.ClientWidth then XInc:=1;
+ else if (RNew.Right + FGCache.TLColOff > FGCache.ClientWidth)
+ and (RNew.Left + FGCache.TLColOff - GetColWidths(aCol) >= FGCache.FixedWidth) then XInc:=1;
+ // Only scroll left if the left edge of the cell does not become invisible as a result
Yinc:=0;
if RNew.Top + FGCache.TLRowOff < FGCache.FixedHeight then Yinc:=-1
- else if RNew.Bottom + FGCache.TLRowOff > FGCache.ClientHeight then YInc:=1;
+ else if (RNew.Bottom + FGCache.TLRowOff > FGCache.ClientHeight)
+ and (RNew.Top + FGCache.TLRowOff - GetRowHeights(aRow) >= FGCache.FixedHeight) then YInc:=1;
+ // Only scroll up if the top edge of the cell does not become invisible as a result
with FTopLeft do
if ((XInc=0)and(YInc=0)) or // the cell is already visible
((X=aCol)and(Y=aRow)) or // the cell is visible by definition
((X+XInc<0)or(Y+Yinc<0)) or // topleft can't be lower 0
((X+XInc>=ColCount)) or // leftmost column can't be equal/higher than colcount
- ((Y+Yinc>=RowCount)) or // topmost column can't be equal/higher than rowcount
- ((XInc>0)and(X=aCol)and(GetColWidths(aCol)>FGCache.ClientWidth)) or
- ((YInc>0)and(Y=aRow)and(GetRowHeights(aRow)>FGCache.ClientHeight))
+ ((Y+Yinc>=RowCount)) // topmost column can't be equal/higher than rowcount
then
Break;
Inc(FTopLeft.x, XInc);
