internal static extern bool GetScrollBarInfo(IntPtr hwnd, uint idObject, ref SCROLLBARINFO psbi);
protected override void UpdateDXScrollBar(bool isHorz)
{
if (IsLockUpdate)
{
return;
}
ScrollBarBase dxScroll = isHorz ? (ScrollBarBase)HScroll : (ScrollBarBase)VScroll;
if (SourceControl == null)
{
return;
}
if (!SourceControl.IsHandleCreated || !dxScroll.Parent.IsHandleCreated)
{
dxScroll.Visible = false;
return;
}
BeginUpdate();
try
{
SCROLLBARINFO sbInfo = new SCROLLBARINFO();
sbInfo.Init();
SCROLLBARINFO.GetScrollBarInfo(SourceControl.Handle, isHorz ? SCROLLBARINFO.OBJID_HSCROLL : SCROLLBARINFO.OBJID_VSCROLL, ref sbInfo);
Rectangle scrollBounds = sbInfo.rcScrollBar.ToRectangle();
if ((SourceControl != null && !SourceControl.Visible) || scrollBounds.IsEmpty || sbInfo.rgstate0 == SCROLLBARINFO.STATE_SYSTEM_INVISIBLE || sbInfo.rgstate0 == SCROLLBARINFO.STATE_SYSTEM_OFFSCREEN)
{
dxScroll.Visible = false;
return;
}
scrollBounds = dxScroll.Parent.RectangleToClient(scrollBounds);
if (isHorz)
{
scrollBounds.Height = fWidth;
}
else
{
scrollBounds.Width = fWidth;
}
dxScroll.Bounds = scrollBounds;
ScrollArgs currentArgs = new ScrollArgs(dxScroll), args = new ScrollArgs();
if (sbInfo.rgstate0 == SCROLLBARINFO.STATE_SYSTEM_UNAVAILABLE)
{
args.Maximum = args.Minimum = 0;
args.Value = 0;
args.Enabled = false;
}
else
{
SCROLLINFO sInfo = new SCROLLINFO();
sInfo.Init();
SCROLLINFO.GetScrollInfo(SourceControl.Handle, isHorz ? SCROLLINFO.SB_HORZ : SCROLLINFO.SB_VERT, ref sInfo);
args.Enabled = true;
args.Maximum = sInfo.nMax;
args.Minimum = sInfo.nMin;
args.LargeChange = sInfo.nPage;
args.SmallChange = isHorz ? 8 : 1;
args.Value = sInfo.nTrackPos;
}
dxScroll.Visible = true;
if (currentArgs.IsEquals(args))
{
return;
}
args.AssignTo(dxScroll);
}
finally
{
EndUpdate();
}
}
