internal CellRange GetViewRange(Point scrollPosition)
{
// get size, position, range
var sz = DesiredSize;
// account for frozen rows/columns
var fx = Columns.GetFrozenSize();
var fy = Rows.GetFrozenSize();
var r = new CellRange(Rows.Frozen, Columns.Frozen);
//var sv = _grid.OuterScrollViewer;
//if (sv != null && (_grid.OuterScrollViewerVerticalScrollEnable || _grid.OuterScrollViewerHorizontalScrollEnable))
//{
// if (_grid.OuterScrollViewerVerticalScrollEnable)
// {
// sz.Height = sv.ActualHeight * 1.5;
// var y = _grid.HeaderActualHeight - sv.VerticalOffset;
// y += _grid.topToOuterScrollViewer;
// r.Row = Rows.GetItemAt(-y - sv.ActualHeight);
// r.Row2 = Math.Min(Rows.GetItemAt(sz.Height - y), Rows.Count - 1);
// }
// else
// {
// if (fy < sz.Height)
// {
// sz.Height = sv.ActualHeight;
// r.Row = Rows.GetItemAt(fy - scrollPosition.Y);
// r.Row2 = Math.Min(Rows.GetItemAt(sz.Height - scrollPosition.Y), Rows.Count - 1);
// }
// }
// if (_grid.OuterScrollViewerHorizontalScrollEnable)
// {
// // find left/right columns
// sz.Width = sv.ActualWidth * 1.5;
// var x = -sv.HorizontalOffset;
// r.Column = Columns.GetItemAt(-x - sv.ActualWidth);
// r.Column2 = Math.Min(Columns.GetItemAt(sz.Width - x), Columns.Count - 1);
// }
// else
// {
// if (fx < sz.Width)
// {
// sz.Width = sv.ActualWidth;
// r.Column = Columns.GetItemAt(fx - scrollPosition.X);
// r.Column2 = Math.Min(Columns.GetItemAt(sz.Width - scrollPosition.X), Columns.Count - 1);
// }
// }
//}
//else
{
// find top/bottom rows
if (fy < sz.Height)
{
r.Row = Rows.GetItemAt(fy - scrollPosition.Y);
r.Row2 = Math.Min(Rows.GetItemAt(sz.Height - scrollPosition.Y), Rows.Count - 1);
}
// find left/right columns
if (fx < sz.Width)
{
r.Column = Columns.GetItemAt(fx - scrollPosition.X);
r.Column2 = Math.Min(Columns.GetItemAt(sz.Width - scrollPosition.X), Columns.Count - 1);
}
}
if (r.Row < 0)
{
r.Row = 0;
}
if (r.Row2 < 0)
{
r.Row2 = 0;
}
if (r.Column < 0)
{
r.Column = 0;
}
if (r.Column2 < 0)
{
r.Column2 = 0;
}
// done
return(r);
}
protected override Size ArrangeOverride(Size finalSize)
{
UpdateViewRange();
CellRangeDictionary showCells = new CellRangeDictionary();
foreach (int r in Rows.EnumerateVisibleElements(_viewRange.TopRow, _viewRange.BottomRow))
{
var left = _viewRange.LeftColumn;
// enumerate visible columns
foreach (int c in Columns.EnumerateVisibleElements(left, _viewRange.RightColumn))
{
var rng = new CellRange(r, c);
showCells[rng] = null;
}
}
// remove cells that are shown but shouldn't be
List <CellRange> removeCells = new List <CellRange>();
foreach (var rng in _cells.Keys)
{
if (!showCells.ContainsKey(rng))
{
removeCells.Add(rng);
}
}
// create cells that should be shown but aren't
foreach (var rng in showCells.Keys)
{
CreateCell(rng, removeCells);
}
for (int i = 0; i < removeCells.Count; i++)
{
RemoveCell(removeCells[i]);
}
foreach (KeyValuePair <CellRange, FrameworkElement> kvp in _cells)
{
// avoid re-creating the range based on element (for performance)
var rng = kvp.Key;
var cell = kvp.Value;
if (rng.Row < 0 || rng.Row >= Rows.Count ||
rng.Column < 0 || rng.Column >= Columns.Count)
{
cell.Visibility = Visibility.Collapsed;
}
else
{
// get rectangle to arrange cell
var rc = GetCellRect(rng);
//fix auto column,if Width is Auto and AdaptUISize is true, the width will the adapt to UI width.
if (Columns[rng.Column].AdaptUISize)
{
cell.Measure(new Size(double.PositiveInfinity, double.PositiveInfinity));
if (cell.DesiredSize.Width > rc.Width)
{
rc.Width = cell.DesiredSize.Width + 5;
Columns[rng.Column].SetSize(rc.Width);
Columns.SetIsDirty(true);
//if Cell has dirty data, we should also update Column
if (CellType == CellType.Cell)
{
//Grid.ColumnHeaders.Invalidate();
}
//Column always render before cell, so we don't need invalidate cell right now.
////if column has dirty data, we should also update cell
//else
//{
// Grid.Cells.Invalidate();
//}
}
}
// set clipping to account for frozen rows/columns
if (Rows.Frozen > 0 || Columns.Frozen > 0)
{
cell.Clip = null;
if (!Columns.IsFrozen(rng.Column) || !Rows.IsFrozen(rng.Row))
{
// no clipping yet
var rcClip = new Rect(0, 0, rc.Width, rc.Height);
// clip unfrozen columns
if (!Columns.IsFrozen(rng.Column))
{
var fx = Columns.GetFrozenSize();
if (fx > 0 && rc.X < fx)
{
rcClip.X = fx - rc.X;
}
}
// clip unfrozen rows
if (!Rows.IsFrozen(rng.Row))
{
var fy = Rows.GetFrozenSize();
if (fy > 0 && rc.Y < fy)
{
rcClip.Y = fy - rc.Y;
}
}
// activate clip
if (rcClip.X > 0 || rcClip.Y > 0)
{
cell.Clip = new RectangleGeometry()
{
Rect = rcClip
};
}
}
}
// limit editor size to grid cell (so trimming will work)
cell.Width = rc.Width;
cell.Height = rc.Height;
// to finish the layout
cell.Measure(new Size(rc.Width, rc.Height));
cell.Arrange(rc);
}
}
// measure content
return(new Size(_cols.GetTotalSize(), _rows.GetTotalSize()));
}