protected override Size GetPreferredSize(Graphics graphics, DataGridViewCellStyle cellStyle, int rowIndex, Size constraintSize)
{
if (DataGridView == null)
{
return(new Size(-1, -1));
}
if (cellStyle == null)
{
throw new ArgumentNullException(nameof(cellStyle));
}
Size preferredSize;
Rectangle borderWidthsRect = StdBorderWidths;
int borderAndPaddingWidths = borderWidthsRect.Left + borderWidthsRect.Width + cellStyle.Padding.Horizontal;
int borderAndPaddingHeights = borderWidthsRect.Top + borderWidthsRect.Height + cellStyle.Padding.Vertical;
DataGridViewFreeDimension freeDimension = DataGridViewCell.GetFreeDimensionFromConstraint(constraintSize);
int marginWidths, marginHeights;
string formattedString = GetFormattedValue(rowIndex, ref cellStyle, DataGridViewDataErrorContexts.Formatting | DataGridViewDataErrorContexts.PreferredSize) as string;
if (string.IsNullOrEmpty(formattedString))
{
formattedString = " ";
}
TextFormatFlags flags = DataGridViewUtilities.ComputeTextFormatFlagsForCellStyleAlignment(DataGridView.RightToLeftInternal, cellStyle.Alignment, cellStyle.WrapMode);
// Adding space for text padding.
if (DataGridView.ApplyVisualStylesToInnerCells)
{
Rectangle rectThemeMargins = DataGridViewButtonCell.GetThemeMargins(graphics);
marginWidths = rectThemeMargins.X + rectThemeMargins.Width;
marginHeights = rectThemeMargins.Y + rectThemeMargins.Height;
}
else
{
// Hardcoding 5 for the button borders for now.
marginWidths = marginHeights = DATAGRIDVIEWBUTTONCELL_textPadding;
}
switch (freeDimension)
{
case DataGridViewFreeDimension.Width:
{
if (cellStyle.WrapMode == DataGridViewTriState.True && formattedString.Length > 1 &&
constraintSize.Height - borderAndPaddingHeights - marginHeights - 2 * DATAGRIDVIEWBUTTONCELL_verticalTextMargin > 0)
{
preferredSize = new Size(
MeasureTextWidth(
graphics,
formattedString,
cellStyle.Font,
constraintSize.Height - borderAndPaddingHeights - marginHeights - 2
* DATAGRIDVIEWBUTTONCELL_verticalTextMargin,
flags),
0);
}
else
{
preferredSize = new Size(
MeasureTextSize(graphics, formattedString, cellStyle.Font, flags).Width,
0);
}
break;
}
case DataGridViewFreeDimension.Height:
{
if (cellStyle.WrapMode == DataGridViewTriState.True && formattedString.Length > 1 &&
constraintSize.Width - borderAndPaddingWidths - marginWidths - 2 * DATAGRIDVIEWBUTTONCELL_horizontalTextMargin > 0)
{
preferredSize = new Size(
0,
MeasureTextHeight(
graphics,
formattedString,
cellStyle.Font,
constraintSize.Width - borderAndPaddingWidths - marginWidths - 2 * DATAGRIDVIEWBUTTONCELL_horizontalTextMargin,
flags));
}
else
{
preferredSize = new Size(
0,
MeasureTextSize(
graphics,
formattedString,
cellStyle.Font,
flags).Height);
}
break;
}
default:
{
if (cellStyle.WrapMode == DataGridViewTriState.True && formattedString.Length > 1)
{
preferredSize = MeasureTextPreferredSize(graphics, formattedString, cellStyle.Font, 5.0F, flags);
}
else
{
preferredSize = MeasureTextSize(graphics, formattedString, cellStyle.Font, flags);
}
break;
}
}
if (freeDimension != DataGridViewFreeDimension.Height)
{
preferredSize.Width += borderAndPaddingWidths + marginWidths + 2 * DATAGRIDVIEWBUTTONCELL_horizontalTextMargin;
if (DataGridView.ShowCellErrors)
{
// Making sure that there is enough room for the potential error icon
preferredSize.Width = Math.Max(preferredSize.Width, borderAndPaddingWidths + IconMarginWidth * 2 + s_iconsWidth);
}
}
if (freeDimension != DataGridViewFreeDimension.Width)
{
preferredSize.Height += borderAndPaddingHeights + marginHeights + 2 * DATAGRIDVIEWBUTTONCELL_verticalTextMargin;
if (DataGridView.ShowCellErrors)
{
// Making sure that there is enough room for the potential error icon
preferredSize.Height = Math.Max(preferredSize.Height, borderAndPaddingHeights + IconMarginHeight * 2 + s_iconsHeight);
}
}
return(preferredSize);
}
