protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
var g = e.Graphics;
g.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.Half;
g.DrawRectangle(Pens.MediumVioletRed, 0.5f, 0.5f, this.Width - 1, this.Height - 1);
int totalAvailableWidth = this.Width;
int[] columnWidths = ColumnPositioning.CalculateColumnWidths(this.Columns, totalAvailableWidth, 10, out int totalOccupiedWidth, out int totalFillableWidth);
Debug.Assert(columnWidths.Length == this.Columns.Length);
const int columnHeight = 20;
int scrollPosition = this.GetHScrollValue();
int x = -scrollPosition;
for (int i = 0; i < this.Columns.Length; ++i)
{
// Column out of bounds (right). Don't need to draw any more columns.
if (x > totalAvailableWidth)
{
break;
}
var col = this.Columns[i];
var columnWidth = columnWidths[i];
if (x + columnWidth < 0)
{
// Column out of bounds (left). Go to next column until we find one to draw.
x += columnWidth;
continue;
}
double effectiveFillPercentage = (double)(columnWidth - col.Width) / totalFillableWidth * 100.0;
Brush fillBrush = Brushes.Gray;
g.FillRectangle(fillBrush, x, 0, columnWidth, columnHeight);
int borderWidth = i == this.Columns.Length - 1 ? columnWidth - 1 : columnWidth;
g.DrawRectangle(Pens.Black, x + 0.5f, 0.5f, borderWidth, columnHeight - 1.0f);
TextRenderer.DrawText(g, FormattableString.Invariant($"{col.Width}/{col.FillWeight} = {columnWidth} | {effectiveFillPercentage:F1} %"), this.Font, new Point(x, 0), Color.White);
x += columnWidth;
}
var sb = new StringBuilder();
foreach (var width in columnWidths)
{
sb.AppendLine(width.ToString());
}
sb.AppendLine($"Total available: {totalAvailableWidth}");
sb.AppendLine($"Total fillable: {totalFillableWidth}");
sb.AppendLine($"Total occupied: {totalOccupiedWidth}");
TextRenderer.DrawText(g, sb.ToString(), this.Font, new Point(0, columnHeight), Color.Black);
}
protected override void OnMouseDown(MouseEventArgs e)
{
base.OnMouseDown(e);
if (e.Button != MouseButtons.Left)
{
return;
}
int[] columnWidths = ColumnPositioning.CalculateColumnWidths(this.Columns, this.Width, 10, out _, out _);
ColumnPositioning.HitTest(columnWidths, this.GetHScrollValue(), e.X, 5, out int columnIndex, out bool resizeHandle);
if (resizeHandle)
{
this.resizeDragInfo = new ResizeDragInfo(this.Columns[columnIndex], e.X);
}
}
protected override void OnMouseMove(MouseEventArgs e)
{
base.OnMouseMove(e);
if (this.resizeDragInfo.Active)
{
this.Cursor = Cursors.VSplit;
ColumnPositioning.ResizeDrag(this.resizeDragInfo, e.X, 10);
this.RecalculateScrollBar();
return;
}
int[] columnWidths = ColumnPositioning.CalculateColumnWidths(this.Columns, this.Width, 10, out _, out _);
ColumnPositioning.HitTest(columnWidths, this.GetHScrollValue(), e.X, 5, out _, out bool resizeHandle);
this.Cursor = resizeHandle ? Cursors.VSplit : Cursors.Default;
}